2004 monterey 4.2 Misfire when cold
 

I have a 2004 Monterey with the 4.2 Right after we just got it we noticed that after it has sat for awhile, overnight, it will misfire till you get it warmed up a little bit. That takes about 2 miles down the road. I just changed all the plugs, coil, plug wires, and put in a new fuel filter and that did not solve the problem. After it has warmed up, it is fine. the plugs I took out did not look bad. The van only has 54,000 miles on it. We did not notice it when we bought it, as it was always warm when we drove it. It does not throw a code or have any light on at all that would lead me to what to check. I do notice when I am driving and it misses, I hear what sounds like a "HISS" or "TISS" maybe and it sounds like it is coming from the passenger side dash up near the firewall???? I am at a loss, if anyone has any ideas I would love to hear them. Thanks!

Well, I just had a similar problem on my Mom's Monterey, only the car would completely die out sometimes. The mechanic said it was a crankshaft position sensor, which makes sense because I had the same problem in my jeep.


It never threw a code in my jeep or in my mom's van either. In either regard, it's a relatively cheap solution to check. It's a 50 dollar part, and shouldn't take very long to get the old one off and the new one on.


I do have a question though (sorry to thread jack, but it goes along with your question). Do you need to replace the camshaft synchronizer as well, or is it usually just the sensor?