P0302 code

[KingFish]

Chrysler van started jerking bad while driving. Thought it was transmission at first. Checked code which indicated cylinder 2 misfire. Pulled plug wire off #2 plug and did not see a spark jumping. A screw driver in side the wire and close to the ground showed a weak color spark. I pulled the other end off the coil and with the screw driver grounded, It had a strong spark jumping.

The muffler sounds like it is clogged in back with not much pressure out the tail pipe. I went out and bought spark plugs and wires and replaced the 2,4,6 plug and wire. Cleared the code and took it for a drive. The drive was not jerky but the check engine light came on and just flashed during acceleration. It stops when you let off the gas or give it a little bit of gas.

The acceleration feels bogged and muffler sounds like it has a rattle. I hope to replace muffler over the weekend and see if that helps. Would this have anything to do with a P0302 getting set? I know it is a long shot. On a tight budget, I do not want to throw lots of money at it. engine has 115k miles and the rest of the van has 187k.

[GWguy]

OBD-II Trouble Code: P0302 Cylinder 2 Two Misfire Detected

http://engine-codes.com/p0302_chrysler.html

[KingFish]

If it was a •Faulty catalytic converter(s), I would expect another code like sensor bank 2 or something. Too many things to track down. A muffler is a lot cheaper than converter.

[Crewdawg141]

Originally Posted by KingFish

If it was a •Faulty catalytic converter(s), I would expect another code like sensor bank 2 or something. Too many things to track down. A muffler is a lot cheaper than converter.

I had a similar issue with my Dodge Ram, the problem was a clogged Cat. It was giving me one cylinder code and then the code for random misfire. It also lacked power and progressively got worse. If you can disconnect the rear of the exhaust system, try to do so and see if the misfire clears instantly. That is how I managed to finally determine that is was a faulty Cat.

It was just over 180,000 miles when this issue arose in my truck.

[KingFish]

Originally Posted by Crewdawg141

I had a similar issue with my Dodge Ram, the problem was a clogged Cat. It was giving me one cylinder code and then the code for random misfire. It also lacked power and progressively got worse. If you can disconnect the rear of the exhaust system, try to do so and see if the misfire clears instantly. That is how I managed to finally determine that is was a faulty Cat.

It was just over 180,000 miles when this issue arose in my truck.

That is this weekends project. My SUV has a CEI light on steady for a bad CAT and ha sa code that says P0430 catalyst system bank 2. I would think the van would do the same instead of Cylinder 2 misfire. I am thinking of replacing the coil anyway to be on the safe side. This is an engine that came from a salvage yard to replace the one that started knocking really bad.
6 months on it and now this issue has come up. Lucky me.

[Crewdawg141]

Originally Posted by KingFish

That is this weekends project. My SUV has a CEI light on steady for a bad CAT and ha sa code that says P0430 catalyst system bank 2. I would think the van would do the same instead of Cylinder 2 misfire. I am thinking of replacing the coil anyway to be on the safe side. This is an engine that came from a salvage yard to replace the one that started knocking really bad.
6 months on it and now this issue has come up. Lucky me.

Yes, I know it is odd. I do not for the life of me know how or why a Chrysler will throw a misfire code for a bad Cat, but it does. I was lucky enough to get a little help from a friend who at the time worked as a mechanic at Waldorf Dodge. He said that the clogging cat and the odd symptoms were quite common in Chrysler products. I learned this after hunting down and troubleshooting or replacing a few different little things (sensors, plugs, coils, etc.).

I am soon to be replacing a Cat in a 2003 Toyota Corolla for a Catalyst Inefficiecy code. Already ran through all other troubleshooting trees for this problem and come back to a faulty Cat but no other code other than a P0420.

[dave1959]

Finish replacing the rest of the plugs and wires first. If you still have a problem then come back and we will chat some more. Make sure you use only
champion plugs and a good set of wires. do not buy the wrong plugs or use cheap wires, you will still have a problem. PM me for more info.

[dave1959]

Originally Posted by Crewdawg141

Yes, I know it is odd. I do not for the life of me know how or why a Chrysler will throw a misfire code for a bad Cat, but it does. I was lucky enough to get a little help from a friend who at the time worked as a mechanic at Waldorf Dodge. He said that the clogging cat and the odd symptoms were quite common in Chrysler products. I learned this after hunting down and troubleshooting or replacing a few different little things (sensors, plugs, coils, etc.).

I am soon to be replacing a Cat in a 2003 Toyota Corolla for a Catalyst Inefficiecy code. Already ran through all other troubleshooting trees for this problem and come back to a faulty Cat but no other code other than a P0420.

Just remember Catalyst Inefficiecy is the result of a problem not a problem in itself. If you do not correct the root problem you will only destroy a good cat.

[KingFish]

Took off early today and went to autozone and picked up a new muffler and a coil pack. It is cold outside and it reminded me why I hate to work on cars. I was going to unbolt the muffler and I noticed it was welded from the factory. I got the saw out and cut the pipe as close to the muffler as possible. I took some strong wire and wired the pipe up so I can see if I have exhaust flow which I did so I am assuming the CAT is not clogged. Took it for a drive and still felt a little boggy and the light came on again flashing. Came back home and seen the same P0302 code. Cleared it and with it getting dark, swapped out the coil. Took it for a test drive and it was smooth and not boggy at all. I got into it to see if the light would come on and it did not. I believe it is solved. I still need to finish replacing the muffler and replace the back 3 plugs and wires. I did not go with Champion. I went with auto lite. I could have saved 4 bucks a plug going with Champion but I did not want to cheap out.

I need to steam clean the engine and replace both valve cover gaskets. The front one is leaking and I cannot see how the back one is doing. When I replace the plugs I will do the gasket as well. I was so glad to get inside where I could warm up.

[Crewdawg141]

Originally Posted by dave1959

Just remember Catalyst Inefficiecy is the result of a problem not a problem in itself. If you do not correct the root problem you will only destroy a good cat.

Yes, I am aware of that. I have done a lot of homework on this one as it is a pricey fix. I have checked voltage on different sensors, replaced O2 sensors, tuned up the car and run through all of the diagnostic charts that I could find for this car. I have found other Corolla owners of this vintage running into this same issue and a Cat swap fixed the issue.