I'm trying to help out my Uncle with his 96 Dodge Caravan. 3.0 engine. it runs extremely rough, and gets rougher in reverse it seems. I've checked the injectors, coil packs, plugs, wires, etc. To no end. I've also checked out the wiring and replaced the PCM with a known good one.

Is it possible a Crankshaft position sensor could make this run really rough? It will idle by itself without having to get into the throttle, which is different from other vehicles i've had where the CPS went out.

Does anybody have any suggestions on this one?

Thanks everyone!

Dosent that have a dist?Does it have any codes?Thats the first thing to check.Rocky

The code it threw was a multiple cylinder misfire code.that's why I started checking coil packs. And this does not have the distributor, it's coil packs.

Don't overlook mechanical problems, such as intake leak, head gasket, etc.

Clean the throttle body!!

Then check for vacuum leaks.


or.....the good and bad news http://consumerguideauto.howstuffworks.com/1996-to-2000-dodge-caravan-6.htm

Rough idle: Rough running in 3.3-liter and 3.8-liter V6 might be due to broken pedestals in the cylinder heads. (1996)


Rough idle: Vehicles equipped with a 3.3-liter or 3.8-liter V6 may lose power and/or buck and miss. Problem can be fixed by disconnecting the knock sensor. (1996-97)

MikeR

You sure about the coilpacks and distributor? We've had 3 3.0's ( 2 in Caravans 95 and a 99, and 1 in a Leb. convertible, 94), all had distributors.

our 99 developed a steady #4 miss, was the ECM. Wouldn't miss 1st start of the day, but if you shut it off, then it'd miss from there on out.

That has to be a 3.3 as they did not make the 3.0 in that year Caravn with a coil pack. The 3.0 is an overhead cam eng and the 3.3 is a pushrod eng. As was said we had some trouble with the pedestals breaking on the rear cyl head from lack of oil becaus the cam bearing would turn in some. Did you check comp ? Ron

I agree with the others, the 3.0 had dist. ign not packs. Either it is a 3.3, 3.8, or it has a dist.

I have seen them (3.3 3.8)break the pedastals but also blow some head gaskets and run puny. Usually when a coil pack goes bad it sends miss-fire codes for 2 individual cylinders, one cylinder means bad plug or wire, multi-cyl is usually something that affects all of them. I have seen a lot of people put Bosche spark plugs in them and cause mis fires, even with new plugs. I would pull the plugs, look for anything on them that shouldn't be there and run a compression test.

I unplugged the knock sensor and it ran abit better, however it still runs rough, I listened to the rear bank and it sounds real bad through a stephoscope. I'm going to do a compression test this weekend.