QuestionQUESTION: I have a 2003 caravan with a 3.3, It was running great and all of a sudden it started to stall out, when i got the van running again it would not go over 1000 rpm. I found that the egr valve had melted the vacuum hose, I replaced the valve and it ran great after about 25 mins of running the van started to have the same problems all over again. I replaced the spark plugs and the valve this time and then the it did the same thing all over again. I noticed that as the van is running it smells like exhaust coming from the vacuum line. Is it possible that the cat is causing the problem.
ANSWER: Hi Leo,
The catalytic converter clogging up could certainly cause there to be back-pressure in the combustion chambers that might well cause that odor, and of course the temp rise in the exhaust system would be experienced at the egr. So it is a plausible idea. Do you hear any rattling coming from the vicinity of the cat which can be a sign that the honeycomb has come loose and could thereby be off-axis and blocking the flow of exhaust gas? I believe an independent muffler shop is equipped to measure for that possibility and be less inclined to want to sell you something if you don't need it.
The other approach would be to see what kind of fault codes the powertrain control module has stored in its memory. Use the ignition key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see if any 4-digit numbers preceded by a P show up in place of the mileage. Let me know what those are and we'll go from there.
Roland
PS Please 'rate' my answer, and where you see the question about "volunteer of the month" consider giving me a 'yes' vote. Thanks
---------- FOLLOW-UP ----------
QUESTION: Sorry that it took so long Roland I didnt have Internet back till now. I do not have any codes in the computer or anything like that. I removed the cat and I can get it to run well over 4000 rpm. When im driving the van it works good but as soon as I let it idle in or out of gear it wont stay running. It runs smooth when its driving over 2mph. It smells almost like raw gas and blows black smoke. I can get it to start back up everytime. What would cause an over fueling issue? Is it possible to be the plugs? They are autolite and I normally run champions in all chryslers.
AnswerHi Leo,
I'm glad to hear back from you.
The engine can't run that badly without setting some sort of a code, I would believe. Did you try a plug-in code reader (via the under-dash next to steering column reader socket)? If not, you can get such a readout for free at an Autozone parts store or for under $40 at an independent garage. Other than the egr being ajar or a sensor which is off-value but not so much as to set a code I can't identify any other cause. I doubt the spark plugs would be such a factor. Let me know any 4-digit codes that come from a readout and we can go from there. Other than that i can't give you anyother possibilities for a no idle sort of situation. The mixture is based upon the coolant temp sensor, the MAP sensor, the oxygen sensors, inlet air temp sensor, throttle position sensor; but there are codes for all those if they are far off-value.
Roland
PS: Please 'rate' my answer, and where you see the question about 'volunteer of the month' if you would consider a 'yes' vote for me that would be appreciated. I just noticed that you were so kind as to do that today about the earlier question. Thank you.
