PontiacBonnevilleClub.com

Hi All....

I'm thinking I have an ignition control module issue.....surges around 45 mph going up hills....

Here is the question..... Does the Ssei have use a different ICM than a base model? Is there a significant difference between the AC Delco module and the Delphi one? There a hundred bucks difference between them at Advance Auto..... I'm not into 'cheap' so I'll avoid their Borg Warner ICM....but since Delphi has been a GM supplier of electronics was just wondering if there is a hundred bucks worth of 'better' in the Delco one....

Thanks for any thoughts...

SC

Same ICM between all models.

I sell good used ones for much cheaper, PM me.

ICM just distributes spark to the coil packs which sends spark through the plug wires and to the plugs themselves. Surging going up hill sounds more of a throttle problem

Sounds like the somewhat-common chugging problem. Supposedly is a design issue in the tranmission controller's programming (assuming that your ignition system and vacuum lines are good); the car doesn't shift early enough when going up low-grade hills and winds up bogging down a bit.

I'd love for somebody to find a fix for this, but after getting into it last year (and replacing several parts) I could not make it stop doing this. Like many others who responded to my query and tried taking this on in the past, I now just live with it. If you tap the gas pedal when this happens, the car will usually downshift in response, and the surging/chugging stops for that instance. If you wish to pursue it further, I would suggest going back and reading the previous discussions here at the Club to get more insight. There was also a GM TSB on the topic, which basically said to make sure your ignition system and vacuum lines were up to code.

Ken_W

Petermcmxii wrote:ICM just distributes spark to the coil packs which sends spark through the plug wires and to the plugs themselves. Surging going up hill sounds more of a throttle problem

Surging is probably the mostly commonly misdiagnosed problem we have here.

A bad ICM is a known problem for surging. A misfire can be attributed to many things including: plugs, wires, coils, ICM, injectors, MAF, etc.

I've never seen a surging problem from a bad TPS. Usually a bad TPS just causes incorrect idling or transmission shifts.

Ken_W wrote: If you tap the gas pedal when this happens, the car will usually downshift in response, and the surging/chugging stops for that instance. Ken_W

That nails it to a tee.....and after further testing....it only does it when in O/D......around 45mph with slight application of the accelerator pedal when going up a slight grade......

I also notice that it seems to diminish as the car gets warmed up......

I'm thinking the ICM may have been a premature thought on my part.....as I had run across it in another thread....but what you described is reproduceable in my car....precicely.....

So, does that condition cause any internal damage if left unchanged?

Petermcmxii wrote:ICM just distributes spark to the coil packs which sends spark through the plug wires and to the plugs themselves. Surging going up hill sounds more of a throttle problem

I thought about that and replaced the TPS a while back....no change....but I'm starting to center in on the TC when in O/D.....

harofreak00 wrote:Surging is probably the mostly commonly misdiagnosed problem we have here.

Get a scantool that can read misfires. I'm 99% sure you will find that you have a misfire problem.