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1991 Honda Civic - Rough Idle
I recently purchased this car for my daughter, it runs well but has the roughest idle! It seems like it has solid motor mounts, its an automatic transmission idle speed is between 900 & 1000 I'm sure the throttle position stuff is bad but don't want to replace the throttle body. It also has a noticeable spark knock. Would the timing be advanced too much cause the idle problem?
Yes, the timing being too far advanced (excessive) could cause a rough running with some vehicles. Hondas are known for distributor problems though I would look into that possibility as well. It could be that the distributor is coming apart inside and is causing this problem or the coil inside the dist is acting up or the cap etc is burnt up inside.
Check all the basics first (cap rotor wires plugs filters) and then go from there. I wouldn't hesitate to check the motor mounts either to make sure that the rubber isn't out of them on one or another and its grounding out metal on metal as you described creating something similar to a solid motor mount.
Rough Idle, Sometimes Dies
I have a 93 Nissan D21 pickup 2.4L 5 speed- Manual Trans. I am having problems with a rough idle and sometimes it will die. I have replaced the coil, cap, rotor, wires, & plugs. The only thing that I can think of that might be acting up is the THROTTLE POSITION SWITCH. It did this about a year ago and quit. If it does have plenty of power and runs great at 70-80 mph 2500-3000 rpms. but at that speed as soon as I let off the gas it starts to cut out and jerk.
The throttle position sensor can cause what you're describing but without doing the proper checks it's hard to say if this is the case. If you have access to a digital (high impedance meter) with an ohm scale, you may want to check the resistance across the various terminals. There is a proper check procedure for this and I would recommend you access a manual, which is vehicle specific, and check the tps before buying one. The cost of a manual that pertains to your specific vehicle engine controls is a lot cheaper than flipping a sensor on it again only to find out that it isn't the area that needs attention. It will also help you determine how to access trouble codes that the computer may have already determined as a problem area.
89 Celebrity: Rough Idle & Stalls
No codes set; runs fine otherwise. Changed the EGR and IAC motor. Cold or hot, worse hot. Car jerks when coming to a stop from any speed, like Tec lockup. I suspect a vacuum leak but cannot find one. pcv rattles and strong vacuum at valve cover end.
What are your vacuum readings at idle, they should be in the neighborhood of 18 to twenty one inches at idle . If they are lower than that, then I would be looking for a huge vacuum leak i.e. ,manifold, throttle body base gasket, and or something like that or a large timing discrepancy(retarded).I would also be checking to make sure that fuel pressures are as they should be not to high and not too low(in spec)and also your vacuum readings shouldn't be bouncing(valve problems)You might want to try and chase vacuum leaks with a squirt bottle of water and hit all the spots you might suspect, gaskets joints etc. and see what you can find. Usually when you get water into the intake stream the car stumbles and or runs rough. You might also want to check into the calibration of the map sensor. This also plays a huge roll in the fuel mixture settings in these cases too.
89 Olds - "Check Engine" Light On, Runs Rough
My alternator went in my 89 Olds, ever since I changed it . My computer "check engine" light comes on and it runs rough in drive but better in over-drive. The owners manual says that the light will come on as part of the emission control system. Is this related to the alternnator problem and how do I fix this warning light situation . Anything I can do myself??????
I would check to see that nothing has been knocked off in the process of removal and install of the alt or been pulled out slightly i.e. ,a plug to a sensor, wiring harness pinched somewhere in this vicinity, a hose knocked of something like that.
Failing that ,it would be prudent to get the car scanned and see what it has in it for a failure code and go from there. Sometimes it's quicker to go that route and just go to the source of the problem. A solid on check engine light is usually pretty straight forward to find, but then again....
Nissan Pickup Missing, Burning Rich
My Pickup started missing yesterday coming home. It has done this before and some new plugs and wires took care of this for 9 months. I know she's burning rich and hope you have some advice where to start looking.
You might want to begin with checking the spark plugs again to see what is happening with them as far as the type of burn they have on them. If you pull them out ,check them for the color of deposits that they have on them, black ,Grey, white whatever. They should all be the same whatever it may be. If you have one that is different than the others, that might very well be the cylinder to start looking at, carefully inspect the plug for cracks and or tracking down the electrode or something unusual like that; a damaged plug wire or tracking down the plug where the one is different,etc. If you find any irregularities, let me know what they are and maybe we can go from there.
'90 Plymouth Acclaim - Almost Stalls @ Slow Speeds, Stops
Been having a problem with our 1990 Plymouth Acclaim. When you go to stop or slow for turns the car almost cuts off. If it were an older car, I would say up the idle.... but this one is fuel injected. Have tried plugs and rotor. Would fuel injector-cleaning help? Any suggestions?
Fuel injector cleaning couldn't hurt it ,thats for sure, and it may just help if the injector is really that dirty, assuming that this unit is throttle body fuel and not port fuel injection. Other areas of inspection might be the fuel filter, air filter and pcv valve. Failing those I would recommend scanning the cars computer to get an idea of what is going on (checking data stream) as well as checking to see if you have an appropriate amount of fuel pressure for that vehicles specifics. Another common failure in the four cylinder Chrysler products is bad egr valves that rot off pulling the egr on and or the valve getting stuck open partially causing a stall or really bad idle. A slow or malfunctioning idle air control motor can also cause this not being able to recover from the idle down. Air leaks i.e. hoses off broken or damaged misrouted may also cause this. Hope this gives you some direction.
80 Honda Civic Wagon - Stalls When Slowing to Stop
My car has been stalling when I slow down to stop I have fixed one part of the problem but can't figure out what the rest of the problem is. The engine hisses, and I know its not supposed to do that. Please tell me all you can on this problem and what it might be and how much it might cost to get it fixed. The car runs just fine, unless you slow down and usually you cant ever tell it has stalled until the battery light comes on. Any help would be great !
More than likely you are on to something when you say the car hisses. Usually a hissing noise under the hood indicates that you have a vacuum leak ,which can be caused by a hose that has fallen off or deteriorated to the point where it has collapsed and it is sucking air from somewhere its not supposed to. The best suggestion I can make is to go under the hood and look around with your best ear for the hissing noise. More often than not, you may find that there is a hose that has come off and can be simply reconnected. Cost wise I am not sure what this may involve but I would say probably not a whole lot if this is all it is. If your not sure take it in to a shop and have them listen for the noise you speak of. If its just a simple fix most mechanics have a good ear for the vacuum leaks and can find it quickly.
Stalling While Turning into Parking Spaces, Hitting Brakes
I have a 1992 Mitsubishi Diamante single overhead cam and I have been experiencing stalling while turning into a parking space and hitting the brakes. The engine would idle up then stall out. The Mitsubishi dealer said I should remove the platinum plugs (which it did)then I was told to have the throttle body serviced (which I did)and I still have the same problem. The car has over 100,000 miles on it. Any ideas ??? This problem started after I had a tune up awhile (85,000 miles) back.
I am not sure on your exact application as we do not have the Mitsubishi cars in Canada. I would assume that they have some sort of a power steering switch on these as most fuel injected models do and its job is to tell the computer to kick up the idle and maintain it till the power steering load has gone away. You might want to look into this and see what happens ,either that or I would be looking for a vacuum hose or source somewhere that has been knocked off that is in an obscure location that may have been inadvertently broken or damaged in the process of the tune up and went unnoticed .
'90 Chrysler Stalling After Driving For Long Time, Then Slowing
Car starts fine and seems to be running smoothly as far as gear shifting and all. After the car has been highway driven for any length of time and then you slow down to a stop or just slow down to anywhere around 15 or lower it stalls. Always! You could drive around in a city start- stop-go and it will not stall, but if you are highway driving for any length of time - higher speeds, of 80km and up and then slow it will stall. I have had it in to see if they can find the problem but so far, they have absolutely no clue why this happens. Would really love some suggestions to take to the mechanic!
The possibility does exist that you have a fuel problem that is causing the car to stall after a long run and a real long fuel demand .If the fuel filter hasn't been changed in a while I would definitely have it changed just as a matter of course and the fuel pressure checked while this is occurring. The car might have to be monitored (driven) with a fuel pressure gauge attached to the fuel lines while driving the car and simulating the condition (catching it in the act). A computer scanner, monitor attached at the same time would be handy as then they can view or review the event to verify its condition at the time of the stall. When this car stalls, does it just peter out and stall or is it abrupt. When it's stalling (I'm assuming this vehicle is an automatic) does it chug and push kind of like a standard transmission car with a driver that is new to a standard shift car? If so it might very well be that the " converter lock up" in the transmission is hanging up and causing the car to stall out due to the temperature. If it kind of peters out and stalls, I would still be looking in the direction of fuel.
Another problem that sometimes occurs with hot highway runs is the E.G.R. valve can stick from a really hot run and cause the car to lean out to the point that it will stall at near idle. Unfortunately ,with most phantom stalling problems its usually best if the tech can catch it in the act and verify what has gone away I.e. fuel, spark or compression and that isn't always easy to do but if you can make it do it consistently, maybe you should take the tech for a drive and show them exactly what it does so they know how to simulate it. It may cost a little in diagnosis time and money but can save you a wealth of headaches, parts replaced because of a guessing and huge inconveniences if the vehicle doesn't restart right away.
87 Dodge Van - Sputters As Engine Gets Hot
Dodge B150 Van, straight 6, carb, when the weather is damp (mist/rainy) and relatively cold (like 28-42F) when the engine starts runs fine, but as the engine starts to heat up, the carb seems to choke the engine out. Once engine warms up totally, runs fine. There is a five-minute period where the engine is sputtering. Is there some sort of temporary related control on the carb that is malfunctioning or shorting out during rain? (Again only during moist mornings). Engine runs great any other time.
As a driver, and owner of tons of Chrysler products, I can appreciate your frustration but it can be fixed, they are just really persnickety in the mid- warm stages and need special attention in a few areas. You have to make sure that your heated air system is working flawlessly for starters. This is the little vacuum valve in the air cleaner that when cold allows vacuum to the heated air door (in the snorkel of the air cleaner). It closes the door to outside air and draws heated air through the heat stove tube (big black or silver flexible tube) that comes from the heat stove (surrounds the exhaust manifold with an outlet for the tube to plug onto). This all must be functioning. Making sure this is all correct will make sure to correct any carb icing that may be occurring.
I have also discovered in my own experience that setting the carb just a little to the rich side helps with this problem as well. You also have to make sure that the heat riser valve exists and is not seized or sticking in the open position to allow the engine to warm properly and it also helps with the midwarm stumble. If its a later model unit that incorporates an egr valve it may be that the egr temperature switch may be malfunctioning and allowing egr function too early in the warm up stages when the engine cannot afford to be leaned out that much.
Pinging and Stalling -After Long Drives- Engine
I have a Jeep Grand Cherokee. It pings pretty much, all the time. I know that it isn't the gas. Also, my engine stalls after I have taken a long drive, usually after about 100 miles or so. I believe that it is a vacuum leak of some sort. I think that the problems are one in the same. Any suggestions?
Well, there is a possibility depending on the year of this jeep that it has a timing problem or even an egr valve that might be sticking or non functional (causing the vacuum leak you mentioned). If you were to repots with the year and engine size I might be able to elaborate more.
Cutting Out At Low Speeds after Long Drives & When Little Gas
I have a 91 Cadillac with 180,000 miles. I just had a major tune-up, new everything $1400 worth.
1. Engine cuts out at low speeds when I drive for more than 2 hours. If I turn off the engine and wait 10 or 15 minutes it is OK.I loosened the gas cap thinking it, was getting a vacuum lock?
2. When I let the gas tank get down very low 2-3 gallons, it cuts out going around a corner. Do you have any suggestions??? Every time I take it the dealer, it is a $1000.00$1400.???? That's practically a major re-build, I'd say. If you just had this done, whether it cut out before or not, I'd take it back to that shop and demand they fix it."At Their Expense". You can put an awful lot of parts and labor into a car for that much. I'd expect it to running like it just came off the floor. The way it's cutting out, it sounds like they may have done some carb work that didn't turn out right.
Another Answer :
Looking at this objectively I would ask what exactly did they do tune up related for $1400.00? I can't imagine how this all could have been tune up related but anything is possible I suppose. Included in this tune up stuff was there a whack of other stuff unrelated like maybe maintenance items (timing chain, belts , bad sensors, relays or something)(maybe even brake or front end work) I am not trying to be critical but I have done jobs where i.e. I was asked to do a general check over and perform necessary repairs .The car then got brakes ,trans service, filters, front end work ,whatever and maybe a set of plugs and a quick set up. No complaints about the running were mentioned at the time the vehicle was brought in. Now the customer brings the vehicle back in and is screaming because the they just spent 1500.00 and it's doing something undesirable with the way it runs. The tune up portion of the bill might be 10% of it and now I have a customer that is angry with me because It runs badly and they aren't willing to spend any more money on it because they already spent a fortune on it and now I feel obligated to fix it and should this be free?
This is just one example of poor communication that can occur between mechanics and the customers. I am not suggesting that this is the case with your car but it's a pretty common occurrence. If the customer had brought it in and told me that there was a stalling problem or something that concerned them most and I had gone through the effort to dig into it a little deeper, get all the details and or explained to them that I was just doing minor tune up items (obvious maintenance) first and see if this would correct it, then this miscommunication may never have occurred. Myself, I try to make sure that my customer understands these details ,so there are no heartaches after the fact. My employers usually think I spend too much time with my customers explaining things in too much detail, but I find it helps immensely in situations like this one. If your customer understands what your doing and why, problems with huge bills don't exist because they are fully aware of all the whys and wherefores.
In any event, I would suggest that you take it back to the same dealer ,explain in great detail what the car is doing, and ask them to give you an estimate of repair before commencing with any more repairs. If you tell them point blank that you are willing to pay for diagnosis time to find the problem and not just put parts on , this will give you the opportunity to question what it is they are doing for your money and at this point you will be able to say "are the repairs you about to do going to fix the problem I am having" and at that point the responsibility is theirs to say yes or no. Diagnosis time can be cheap in comparison to replacing huge expensive parts.
Rough Idle on Start-Up & Stops Running If Left Idling Too Long
1990 Bronco, 5.8, EFI, Cold Start
When I start my Bronco, the engine idles rough for 1-2 minutes and smoothes out after that. It still seems sluggish and sometimes misses under load. It has died the last two times I let it idle for approx. 5 minutes or more. I took it to the garage and they said an error code registered in the computer indicating a bad oxygen sensor. I replace the sensor but still have the same problems. I'm not as concerned with the rough idle as I am the stalling out while idling. It won't start for hours after it dies, and that's unacceptable here in Iceland where I might have to wait out a severe white out in my vehicle. Any ideas?
The oxygen sensor code that they got out of the vehicle computer may be as a result of another problem or just a result of the type of use the vehicle sees. If the vehicle is left to idle for extended periods of time it can contaminate the oxygen sensor .If the 02 saw a problem with lean too often ,it may been as a result of a vacuum leak, hose leak, intake leak, throttle body gasketleak, egr leakage ,something causing excess air to get into the intake stream that the system didn't account for .If this happened the 02 would see it as system lean too long and would set an engine code and not actually be a problem with the O2 , .the opposite would apply (rich condition too long)if you had a leaking injector ,improper fuel pressure ,or something of that nature. Not to say that 02 sensors do not fail. They are damaged very easily by contamination of fuels and cleaners and normal use does take its toll. The O2 sensor also doesn't play any part in the warm up from, cold start till closed loop operation(warmed up) outside of the fact that it has to start switching rapidly from rich to lean within a specific time frame before the computer will go into warm running mode (closed loop).Other than that the o2 values it produces are disregarded by the vehicle computer during the warm up cycle. I would be tempted to start from the basics and make sure that the vehicle tune up status is in check and that all timing, and minimum idle is within specs. When setting the minimum idle you might want to make sure that the throttle body has been spotlessly cleaned and that the idle air control motor is clean or cleaned as well. Once this ground has been covered and if it hasn't produced positive results, then you can go on to further checks which may lead you to deeper testing but possibly more effective results.
88 Dodge Caravan - Stalls Unless RPM Over 1,000
My 88 Dodge Caravan with a 3.0L Van starts and immediately stops, unless you keep the RPM over 1,000. As soon as it gets below it dies. I can drive it and it runs fine again as long as the RPM are over 1,000. If I stop for a stop sign it dies and I have to start it in neutral and then dump it into gear to go.
Well ,it is a possibility that you have a huge vacuum leak of some sort that is causing the vehicle to be incapable of idling on its own i.e. a large vacuum hose that's off...possibly a pcv hose or elbow, maybe a broken vacuum connector at the brake booster or something like that possibly even the booster itself is rotted out . Have someone keep it idling for you while you look around under the hood for a huge vacuum hissing noise and trace it to whatever.
The other possibility might be a ais ,iac motor..Automatic idle speed motor or idle air control motor. If it is stuck or malfunctioning, it may also cause this problem. If you cannot find anything hissing as I had mentioned earlier, look into having this unit scanned or cycle the key on and off three times to have the computer tell you what codes are present and see if any of them are related. One nice advantage to a Chrysler product is that these codes are displayed by flashes of the power loss or check engine light when the key is cycled of and on three times and then left on. You will get two digit codes flashed at you one by one...i.e. five flashes and then five flashes again indicating a code fifty-five. If you do get codes out of it let me know what they are and I can decipher them for you.
Renault Cleo Diesel - Random Engine Cutout
I have a Renault Cleo 1900 diesel. I am experiencing problems with the engine cutting out for no apparent reason. It can happen any time; there is no pattern to it. It could be once a week, twice a day or it might not happen for a few weeks. It can happen at any speed. When it happens it feels like it has run out of diesel, although this isn't the problem and it just stops. It also lets out a cloud of white smoke. It starts again immediately and the smoke clears then it runs perfect again. I have had it in a garage several times and they are baffled they can't find anything wrong. All the obvious things like air in filters fuel lines have been checked. The diesel housing cover has been replaced, glow plugs. The engine has been fine-tuned and the overhead cam belt replaced.
Would you have any idea what could be causing this type of problem? I realize it's difficult with out driving the car but I would be grateful for any suggestions or possibilities that we could explore.
I am not familiar with a Renault Cleo diesel but I can tell you what is common to most diesels. Phantom stalling can be caused by the fuel system sucking air from a bad hose or fitting connection somewhere or a rusty line anywhere in the system that has a miniscule hole in it. Not necessarily capable of leaking on to the ground but enough to allow air to be drawn into the system. A bad pump could also be a concern here.
My biggest concern would be the white smoke. Generally white smoke is and indication that there is coolant or water in the system somewhere being burnt by the engine. If the fuel system has water in it somewhere, i.e., a water trap or in the bottom of the tank caused by condensation that has to be corrected first. Unfortunately, any combustion engine you speak of doesn't run well or at all on water.
The other possibility you might want to check into is if there is a head gasket problem or head or block that is allowing coolant into the combustion chamber. Ask your mechanic if they have done a block test, which is a dyed liquid that you pull radiator gases through and determine if any combustion gases are present in the radiator. This will tell them if there is a leak of coolant into the combustion area generally and may be an answer to your problem . I would check all these areas first and go from there. Generally speaking though ,you would notice a loss of coolant over a period of time if this were the case. Sometimes the loss is written off to normal and not persued.
Random Stalling Problem in '95 Jeep Cherokee Country
After warming up, my jeep will stall usually just once after driving for anywhere from 10 minutes to having driven it all day. My thought is that a caught a bit of water in the line and that is why the problem is intermittent. Any suggestions would greatly be appreciated.
I doubt it's caused by water in the gas line. The problem is more likely a bad sensor or connection.
The first likely culprit is your idle control motor. They have a tendency to get gummed up and cause either stalling or a high idle problem. Take it in, have the air intake, and fuel injectors cleaned. This will also clean out the ICM. This wouldn't be a bad idea in any case especially if you've never had it done. You'd be amazed how much carbon builds up on those things.
Another possibility is a dirty/bad connection to the throttle position sensor or the ICM. Have them pulled apart, cleaned out and replugged in. You should also check the connection to the computer at the firewall.
Another possibility would be the crankshaft position sensor. They go bad quite often on Jeeps but they usually cause a hard start condition, not stalling.
If the problem still persists after cleaning the air intake and the electrical connections, you probably have a bad sensor either the TPS, MAP or maybe the ICM. You really need some good diagnostic tools to determine which is bad so a visit to the dealer would probably be in order unless you want to spend money-replacing sensors until you hit the right one.
I would tend to agree that the likelihood is pretty slim that this problem is caused by water, but hey you never know ..for what its worth buy some gas line anti freeze and put it in!!! Failing that (this will put your mind to rest that this is or isn't the problem). Failing that anything suggested above is possible and then some. If the gas line antifreeze makes no difference as it will allow any water if any to be burnt with the fuel ,than would suggest that you take the vehicle in for diagnostics and see if any trouble codes or failure record is present in the computer and go from there.
In addition, the general condition of tune should be considered as well. Has this unit been tuned recently? Are the ignition wires, plugs and filters all up to snuff? Sometimes the most basic elements of a vehicles tune up condition are overlooked in lieu of more complex expensive items that may or may not be your problem,,,stemming from something basic. Check your service records. Do what you know has to be done anyway(maintenance) and go from there ..
94 Plymouth Voyager Van Stalling Randomly
Engine runs fine, then stalls suddenly with no warning. On trying to restart, the engine cranks but will not fire and all engine gauges (full gauge package) show no response. Removing one battery cable and immediately reinstalling seems to reset the system and engine starts immediately. I have changed cam and crankshaft sensors and computer. In each case the problem went away temporarily and then reappeared suddenly. Engine may run for minutes or days and then just shut down. Removing and reinstalling battery cable seems to correct temporarily. Don't know where to go from this point. Suggestions?
I would check the easy and obvious, first i.e.; fusible links(may be getting disturbed upon moving battery cables)and or nearby battery connectors. All the grounds should be verified as well .Failing that I would also check the relays on the rail on the drivers side to see if any have any signs of corrosion (blue rot on the connectors) and if nothing is found in all of the above you will have to determine what the vehicle is missing when all this occurs i.e. fuel pressure ,injector pulse, spark ?? Then go from there .
85 Ranger Stalling More & More
I was trying to improve my beat up Ranger's performance with those 'dump in the gas and improve your performance' cans and now it stalls all the time (ran rough before, but now is worse). We increase the idle, but now it is just a quick idling staller....especially when I take my foot off the gas to stop (which in turn kills the brakes and steering!!)
Well, you haven't given me much to go on but I'll try to give you some information. I would figure that whatever it is that causes your stalling problem may or may not have been affected by your "mechanic in a can " product. The likelihood that it is coincidence is pretty good and your problem has just progressed further since the time you put the "fix" in the tank. A remote possibility does exist that maybe if, for example, your truck is running too rich and you dump in your fix product which actually does something like clean the injector and now the truck is getting even more fuel which it didn't really need because of a pre- existing problem with something else. In this situation, it may have just made the problem worse.
What I need to know to help you further is information like how many miles are on the truck ,what sort of symptoms does it show like, does it run with a lump to it? Is it running well in the upper rpm range? Does it hesitate to accelerate? Does it show any signs of black smoke when running at what is almost an idle? Does it give you a check engine light when running? .Also ,I am assuming this Bronco is a six cylinder fuel injected model and that all vacuum hoses and general tune up and maintenance conditions have been adequately looked after ?
1987 Pontiac Sunbird Won't Stay Running
I need help. I have a 1987 Pontiac Sunbird with a 2.0 motor and 130,000 miles that I can't keep running. The car set up for several months. It will crank up and Idle but after several minutes or if you press the gas pedal and race the motor up a little it will start making all kinds of popping sound and it smells like its flooded. To recrank it you have to hold the pedal to the floor like when a carburetor is flooded. The car ran for two days although it popped a little from the old gas, then the problem started. The catalytic converter got really hot, glowing red right before it quit. We have since cut it off and replaced it. Do you think that could have damaged something or can you think of something else to try. We have replaced the trottle body and the sensors on it as well and the MAP sensor. Any help would be greatly appreciated.
I get from what your telling me that the car sat for a while ?How long was it sitting? Where? This all may or may not be relative as sometimes after sitting as you are aware, the gasoline loses its volatility and performs really badly. If it sat outside in the elements ,water(condensation) may have got into something it shouldn't have...i.e. the wire ends at the coil pack, the ECM ,a module. Possibly even if it had oil leaks as a lot of the 2.0 litre gm's did maybe the ignition wires were oil soaked and they deteriorated while sitting to the point of leaking high voltage to ground (you can usually see a really terrific light show at night if they are really bad, under the hood ).
The other possibility is that maybe the coil pack itself has gone bad and you are only firing on two or three cylinders. Worst case scenario, but not likely, is that you have a collapsed lifter or some sort of internal engine failure that is causing this poor running. It sounds like you have replaced a lot of parts in lieu of the problem that exists. If you were to take the car in to a trusted repair facility maybe you could just get them to diagnose this for you and replace the faulty parts yourself and save yourself a lot more possibly expensive guesses and save damaging the catalytic converter again by running a whole lot of raw fuel through it again..
It may be something as simple as a fouled spark plug from the bad fuel that was in this vehicle to start with but sometimes when your up against a wall,, getting a professional to check out your problem can be cheaper for you in the long run. At least in this case when whoever it is checks it out and gives you his or her diagnosis,there is no law stopping you from doing the repair yourself .. I can do pretty much anything myself when it comes to repairs but I have run in to instances where my hand has been forced at hiring a professional. Usually because I've thought about it and it might work out cheaper and better for me to let someone else do the job.