Had it to 2 garages now. Had only P0300 initially and they recommended changing the plugs as it's over 100k km but they weren't positive this was the issue. Never had to do that before even in my 02 or 06 but whatever. 3 days later light came back on intermittently solid then flashing and back every couple of minutes. When it was flashing it was running rough and almost stalled out. Took it to the only garage open on a weekend which is a chain and open 7 days a week. They're talking coils and MAP sensor but are unable to determine what the exact issue is either and don't want me to spend another $500 on top of the $450 I spent already this week on plugs. Taking it back to the original chain shop as suggested but not holding my breath.

Why is it they can't determine the exact cause without all this trial and error crap? I don't have money to waste being a single parent and having to take a cab to work and back tomorrow won't help either. Would I be better off getting it towed out of town to one of the nearest Chrysler dealers? Would they have the capability of getting to the cause easier and therefore cheaper? Getting very very frustrated with this. Only had the van 9 months and again never had issues like this with my 2 previous caravans. Thanks in advance.

 

First off I would carry it back to shop that changed plugs for the PO300. Have them check there work as intake had to come off for plugs so gaskets might have been reused causing vacuum leaks which throws vehicle lean so computer dumps a ton of fuel which sensor reads as a rich condition. O2 sensor might have been damaged and needs replaced. Hopefully they won't just read code and throw parts at it.

 

That's what they did the first time. Read the code and cleared it and I brought it back a few days later when the work was to be done. Wasn't impressed by them clearing the code though as I could have gone somewhere else for a 2nd opinion. I will suggest that all to them. Thanks.

 

I understand these situations can be frustrating, but there are a lot of potential causes for a P0300, especially when the PCM isn’t identifying specific cylinders. A few causes are the fuel pump, injectors, coils, plugs/wires, crank or cam sensor, valve timing, head gasket....the list goes on.

Unfortunately the cause isn’t always easily identified and sometimes process of elimination by part replacement is the only choice. That doesn’t mean just throwing parts at it, but basic things like spark plugs should be replaced if needed to rule them out.

Despite what kind of performance you got from your previous vans, the newer they are, the more sensitive they are, and that goes for all makes. Efforts to increase fuel economy means the tolerance for misfires is narrowing every year, and with that, so is the service life of the components.

A good technician can usually narrow down the cause pretty quickly, but sometimes even the best techs will be stumped and you don’t know which one will be servicing your van.

I recommend you find an independent shop. In most cases they are more understanding about tight budgets than chain shops, and sometimes cheaper on labor. They may even be willing to work out an interest free payment plan if needed.

 

ever figured it out?

 

Yes. Was able to meet with my brother in law who is a mechanic in a different city. He looked at it, pulled the codes and right away said O2 sensor (couldn't fix for me as we were at a family gathering). Took that info back to the garage and they changed it and never had a problem with it that way since. It was over $1,000 when all was said and done and that was after they waived some of the diagnostic fees. I've since found a really good independent garage that I can depend on and would only use a chain if no other choice.

 

I thought you said you had a p0300 at first? Did the 02 sensor code pop up later? Or did he run the graph on his scanner to determine the 02 sensor was the culprit?

 

This was three years ago so I really don't remember exactly what happened with the codes. Maybe changing the plugs solved one issue but this other one was in the background. I think the main problem with diagnosing was that it was intermittent and if course never did it when I was at the garage. I trust my brother in law a heck of a lot more than the garages. He said O2 sensor and I got that done and that issue never came up again.