This started about 2 weeks ago, my 2001 gr caravan sport, when first started, runs horrible, pours out black smoke, and will barely pull itself.. When the engine warms up, it runs great, but very rich, and it smells bad. My fuel mileage went from 22 to 10 mpg. There are no codes and no check engine light. When this started, I had a check eng light that had been on for over a year for small evap leak. We scanned it, to see if there were new codes, but none. We turned off the light cleared the evap code, and no new codes, and the light has not come back on. I am not sure if it has anything to do with this problem, but I had filled it with gas the night before it started all this. At this point, we have put in a coolant temp sensor, map sensor, intake air temp sensor, none of these have helped.This is 3.3 flex fuel. Anyone have any ideas, this is my only car, and I really love this van.

 

Open up the wire harness thats next to the power steering resvoir. You may fine some wires shorted together.

 

Have you checked fuel pressure? I don't think you have a test porton the flex fuel model. You have to disconnect the fuel line and install a special "go between" hose with a port. But it depends on year.

I would also check your PCV. My pcv was bad and was fouling the MAP sensor. It ran rough, had poor accelleration, and bad mileage.

 

Yep, +1

 

ramtrk2000, Have you found a solution to your problem. I'm experiencing the same issues. Replaced the MAP sensor with no luck.

The PCV value is unreachable.

Is a short in the wire harness a common issue in these vans? If this was a short, why are there no codes thrown?

Thanks.

 

The wiring in your 1998 is different than a 2001. On yours you need to be looking at the wiring harness where it runs through the front lower center engine mount OR where it runs by the shifter linkage for rubbing. Possibly even the oil dipstick tube bracket. Also, if anyone has had the plenum off to do a tuneup, the wires along the rear of it may be close to the exhaust manifold.

The answer to your question though is that depending on the short or ground condition, and which wires are touching, the values may not not be out of range enough to cause a DTC. Also IF the condition you experience is a sensor shorting, and intermittent, the PCM memory can be erased. Chrysler minvans didn't get crazy "smart" until 2008 when they went to CAN BUS

ramtrk2000 If you can't solve the problem soon, you need to get someone to look at it before you damage your engine or kill your cat converter.

 

TNtech,

Thank you for the additional information.

Well now I'm perhaps one step forward, but two steps back.

I looked in this area and noticed that the was a spark where two ground wires bolt to the engine (under the transmission fluid dipstick tube). The bolt was fairly loose and the connections were very oily. I cleaned the connections and bolted the ground wired tightly.

Now the engine won't turn over. It seems I have gone from a situation where the engine was running too rich to now not having any fuel??

My guess is that disturbing the wire harness perhaps made the short worse (which may confirm a wiring issue, not a sensor issue - one step forward), but now the car won't start and I will most likely need to have the car towed to the repair shop (two steps back).

This site is great and I really appreciate the pointer. Perhaps I am beyond what I can repair myself. Before giving up, any suggestions on how to find a short or ground issue? Any other tips? I think we are on to something and I'm not quite ready to give up.

Thank you.

 

I finally gave in and took it to the dealer, it ended up being o2 sensors. I have only driven it home so far, but it already seems better. They said when the sensors went bad the computer put it in ethanol mode.

 

Ethanol mode eh?