stalling/starting issues (ignition module, egr etc..)

[soopacee]

basically goes like this....was having problems with chug and stall (would be driving fine, next thing rpm all over place, feels like its gonna stall...eventually does)

sometimes when it stalled it was easy to start, other times NO


got the EGR valve replaced and the maf/map sensor (cant remeber which)


problem came right back.....eventually car stalled and wouldnt start, had to get it towed


went to different mechanic, he replaced the ignition module.....ran great for about a month

other day car stalled, wouldnt start.....eventually got it started and didnt have problem YET since




QUESTION is, what should i look at next since all that other stuff was replaced? i heard crank sensor, dont know........any info would be appreciated

[rkvons]

Don't know what year or engine you have, but assuming it's a 3.1, take a look at the connections to the ICM. There are three. The one on the passenger side is voltage in, the one on the driver's side that is two wires is the Cam Position sensor. The other connector on the driver's side is for gauges and other things. You can pull this one out without any real affect, but the other two will cause the engine to die instantly when you pull them out. I would verify those connections and the wires leading to them. The CPS wire is known to be routed wrong sometimes and end up touching the exhaust manifold and melt the insulation. Also, the connectors themselves get worn out. Wiggle all these wires with the engine running and see if you can get it to stall.

[jeffcoslacker]

Don't know what year/engine you got, but some early ones had the problem where the crank sensor's wiring would get slack and rub the crank pulley and ground out when it sagged into it too.

AS said above, a wiring/connector issue is kinda suspect...sometimes with these problems, every time something is replaced it works fine for a while....not because it was the problem, but the subtle change in the wiring harness position from having something unplugged from it and replaced can sometimes "reset" the problem until the wiring sags back into the position causing the problem.

A good place to start with demons like this is to gentle pull, shake, twist, etc every bit of the harness at it's large connectors and at the sensor ends while the motor is fully warmed up and running (if the engine is cold it can be in open loop and ignoring sensor inputs)....sometimes you get lucky and get a stumble or stall when you mess with the piece causing the problem.

The USUAL M.O. for a bad crank sensor is the car starts fine cold, and then at some point while warmed up and running it will break up and die...will usually be hard or impossible to start, and when cooled down it will fire up like nothing happened.

That's not to say it can't happen differently, but that's common....