I feel like I'm starting to throw parts at problems that aren't going away FAST!

[94vertluvr]

Thanks Woll; I was thinking so too but everything I read says if it goes bad it will stall and it's not stalled on me at all. But from you maybe there's more to it. I did take it by a muffler shop and there's nothing wrong with the exhaust...so I'm back to square 1. The muffler shop said it might be a fuel pump but he didn't really look at it or have time to. Today when I was driving it during acceleration it would also sound like it was backfiring in the engine compartment if I pushed it too hard when it was in that power lull. So, it's got to be either fuel or spark at issue; I guess since I don't have all the equipment or know-how to further track it down I'll have to pay a garage to do it...I just hate that...I don't make $75 per hour! LOL

[AL]

I haven't seen a bad icm cause stalling but it will cause what you have going on... There 100 bucks new or you can grab a junkyard one as many vehicles use the same icm... I really wouldn't worry about the different compression ratio on number 5... And the car won't run with the intake off the car so that's why I wasn't sure how you could test your injector

[94vertluvr]

Thanks Al I did price it here for that too...after last weekends $200 lackluster results I was discouraged to try the module...but I have somewhat perfected squeezing my hands in to try and reach those little bolts on the coils so I guess I can do it again. It would be cheaper than having a few tests run at a local shop at $75 per hour. I think I will try the junkyard but they don't warrant electrical parts. Should I try to find an ICM off a different car, maybe a newer car? Do you know what models would have this same module? I was about to say surely i'd find a good one but you know that damn Murphy...as in Murphy's Law, he lives with me!!! Thanks again!

[AL]

Any 3.1 3100 or 3400 or 3.4 dohc all use the same... My opinion is look for a low mile 3100 car or a 3400 car as they are mounted on top the engine away from the heat making them last longer

[Mach 5]

I dont know about stalling my car I had the icm go it wasn't firing 5/2 and 4/1 was firing slow and it didn't stall but it had a lack of power and sounded alot different. it wasn't a coil either. what I usually do is take a timing light to each one of the spark plug wires so you can see the pulses of the ignition at idle adn high idle if ones pulsing slower than the rest then you know where to look. Its work for me a bunch of times ive found bad plugs, wires, and the like this way.

[94vertluvr]

Thanks and thanks to Al...I will be visiting my local 'treasure yard' today in search of a replacement ICM. I feel like this is probably the problem the more I think about it...there are times like this morning that it acts like it is not getting spark and I've replaced all the other spark related things so process of elimination I guess...but you can bet all those parts I took off that didn't fix it will go right back on my garage shelf for future use!!! Will report when I get it installed.

[Brian P]

Good luck, keep us posted.

 

When ICM's fail, they create many different kinds of symptoms. Go grab one from a 3100/3400 from the mid '90s- mid '00's as already mentioned.

[94vertluvr]

Well...I changed out the ICM today; I have to say it is improved as far as response goes BUT it is still hesitating and backfiring...popping noises coming out from under the hood sounds like from the drivers side. From 2k - 3k rpms and mainly from 2nd to 3rd gear as you are accelerating it has what feels like a lull in power and if you continue trying to push it for more you will hear the pop corn sounds which is I'm guessing the backfiring.

 

As you can see from the pic of the old ICM it needed replaced...found a nice one at a junkyard what looked like from a 3400 or something because it was clean and the bolts had no corrosion on them at all. Since I've replace all the electrical/spark related items I'm moving on to fuel system. I borrowed from a friend a fuel pump pressure tester. What is the chance that these symptoms could be related to poor valve timing? Does anyone thing these symptoms sound like that in a 3.4 DOHC?

[AL]

Have you had the timing belt done recently?

[94vertluvr]

I had the guy who installed this engine replace the timing belt and he said it needed a tensioner that he also replaced while in there. There was a few other things left undone from his intall so I can see that it would be possible that he did not time it right...is this hard to do? Should I get a garage to look at this? I know on the older vehicles you had to use a timing light...but i'm not at all sure on these and then you turned the distributor...What do you think Al?

[AL]

Has it done this ever since the install?

[94vertluvr]

The timing has not been messed with since the install; it has no run what i consider 'good' since the install; it is a little more responsive now but with the same hesitation issue; would you get the timing looked at?

[AL]

Depends on if there is a member who knows the 3.4 well that's close to you... But if you have replaced everything then maybe its not a bad idea

[94vertluvr]

Yea, I don't think there is anyone close to me...I'm in SC and most of you guys seem to be around OH, PA...lol I grew up in Pa though if that counts! I will look into getting the timing checked just not sure what all there is to it.

[White93z34]

when it backfires what does the tach do?

[94vertluvr]

it looks like it stops when it should be going up; and may go down just a hair.

[nelson480]

did you do coil packs and wires too?

[94vertluvr]

Yes I replaced all 3 coils and the ICM.

[nelson480]

damn thats crazy, may be timing, would you have any shops willing to look at it?

[94vertluvr]

Yep, lol that IS crazy for sure!!! As a matter of fact I just got off the phone with a local guy...he says the book tells him it will take 5 hours to change the timing belt; but agreed to do it for $180 so I'm going to drop it off for him to go in and check to make sure the timing is right. Apparently it is controlled by the computer but he said if the timing is off one mark or tooth that it can screw it up. So, wish me luck with this other than that the car is great!! Just a great big PITA right now!!