Dealership says 2.4 needs new "ignition computer." What part is this?

knowledge8069 · 08-30-2011, 05:24 PM

Hello all. My 2.4 with the GM Supercharger Kit recently started running rough. It sounds like it's choking and will die if put into gear. There is a new engine in it, so I brought it to the dealership because of the engine warranty and they said it is either the coils or the computer controlling the coils/ignition timing.

I have replaced the coils in the past, so I am familiar with the parts. But what exactly is this "ignition computer?" I asked if he meant the PCM and he said no, that this computer controls the firing times, etc. He didn't seem to want to tell me more than that (typical dealership scheme). He said the part is $300.

Does anyone know exactly what part he's talking about? ECM maybe? A remanufactured ECM is only $126 at O'Reilly. I'd like to do it myself, since he said an hour of labor and that means it's easy, but I don't know what part specifically I need to buy. There is a programmed supercharger profile in the car, flashed by the dealership for the S/C kit. Will I need to get this computer reflashed with the profile? Thanks in advance for any advice!

[ion] C2 · 08-30-2011, 05:37 PM

Ignition control module more than likely. It's $142 at AutoZone so $300 dealer price seems to line up.

No retuning necessary.

I have a spare ICM if you want it, $50 shipped. I've just been leaving it around just in case I ever need one.

NoSweat83 · 08-30-2011, 05:43 PM

You should jump on that.

knowledge8069 · 08-31-2011, 08:42 PM

Apparently it was the coils, so I won't have to buy a new computer! Thanks for the help, that diagram is very clear and useful!!

a.graham52 · 09-01-2011, 07:20 AM

how did you determin it was the coils? jw

Caboose73 · 09-01-2011, 04:00 PM

Its probably to late but if i was you id just do the MSD coil swap instead of replacing the coils again especially sense you have the SC it definitely wouldn't hurt to have them.

Heres the link to the swap its real easy to do i have it on mine http://www.j-body.org/forums/read.ph...=424558#424558

rocketfast321 · 09-01-2011, 07:15 PM

98+ 2200 ohv coil pack work great also. And the complete set is like $35 at the junk yard.

lonnie · 09-02-2011, 07:34 AM

Quote:

Originally Posted by [ion] C2

Ignition control module more than likely. It's $142 at AutoZone so $300 dealer price seems to line up.

No retuning necessary.

I have a spare ICM if you want it, $50 shipped. I've just been leaving it around just in case I ever need one.

This is a really nice diagram. Where can we get these if possible?

[ion] C2 · 09-02-2011, 07:57 AM

lonnie · 09-02-2011, 08:53 AM

Quote:

Originally Posted by [ion] C2

No need to be a smart ass...I didn't know if they were in a paid manual or not.

widbyj · 09-02-2011, 12:59 PM

My 2.4 with S/C is noticeably happier with the MSD coils. As some people have pointed out elsewhere they may not actually increase the voltage by much but they do seem to be more stable at higher RPMs, especially when the boost is on. I looked into other options (Neon coils, etc.) but decided to invest in MSD since I'll probably end up going to a multi-spark controller also.

Glad to hear it was 'just' the coils... keep it simple.

Suggestion - Look into Methanol Injection to keep the temps down and power up when running boosted...

Caboose73 · 09-02-2011, 06:25 PM

ya i did the same i was looking at other coils but figured id just go with the MSD ones

[ion] C2 · 09-02-2011, 09:28 PM

Quote:

Originally Posted by lonnie

No need to be a smart ass...I didn't know if they were in a paid manual or not.

Wasn't being a smartass, I was only going to say "Google" so instead I utlized an image. That's where I found the diagram. I searched "LD9 ignition control module" in Google Images.

Next time you ask a simple question, maybe make sure to specify you want the answer in a certain format... (now that's me being a smartass)

knowledge8069 · 09-05-2011, 10:32 AM

The dealership diagnosed the problem. Not sure exactly how they tested this, probably with a meter of some kind. Actually the problem turned out to be the coil housing that was shorting out, not the coils themselves. The person there had stated the problem incorrectly. Seems only the mechanics, not the service managers, know what they are talking about half of the time!

I will keep these MSD coils in mind, I do love a good upgrade!

Thank you for the advice and information!

Caboose73 · 09-05-2011, 01:13 PM

The MSD coils would still fix your problem cause it replaces all that plastic junk under the cover.