Hello everyone here is my story,

I have had the GM S/C kit on my car since the end of june of this year. Kit ran perfectly for 10,000km. Then one day when I was pulling onto the freeway to pass a guy who was merging to slow it all went to crap.

The guy was merging onto the freeway way to damm slow. So I punched it in 3rd gear and zipped around him from about 60km/hr up to about 120km/hr hitting 6psi as usual up to the next exit I needed to get off on. Then that is when all the trouble started.

When I pulled off the freeway the car was sputtering and the check engine light was flashing on/off and the car was running like crap. On the freeway exit I put on my 4 way blinkers and shut the car off. I was like WTF?

Gave it a minute to chill then I started it back up again. The idle was completely off, RPM was bouncing all over the place and the check engine like was flashing on/off.

So I limped my car home. Come out the next morning hoping everything would be ok after cooling down over night. I hoping in my mind that I didnt blow something up.

It started up ok and ran decent until it started to warm up. So I figured I would take it into the dealer as it died driving it into the service bay. I drop it off and here is the fun $1300 dollar storey later.

The technican was a very smart guy. He really knew his stuff. At this point I will just list what he did as far as I can remember from the work order.

-Read engine code
-Misfire on cylinder 1-2
-Checked plugs, all were burning properly
-Checked gas b/c he thought it may have been bad gas. I run 94 octane eco blend b/c it didnt smell like gas or burn like gas. I have been running it in my car for 6 months no problem. so gas wasnt problem.
-Disconnected fuel line and ran off other premium gas in container, Same misfire and crappy idle
-thought it may have been a bad cat converter, So he dropped downpipe to test. Same thing.
-Did a compression test, All cylinders are good.
-Tested all fuel injectors. They are all within spec and even higher efficiency then new cars injectors.
-Replaced spark plugs with the same GM S/C kit AC Delco plugs gapped to .50 like kit instructions say same as the old plugs.
-He determined it to be the coil pack and the module. so those were replaced.
-He replaced the module and coils and car seems to run better.

And that is how I got it back. The car was still misfiring like crazy. So I headed to the resource I know best. My buddy LafNgas. He was a big help in trying to resolve this matter. After doing alot of talking with him he said he bet it was a plugged cat converter even though the mechanic pulled the downpipe off. He said it would still run like crap b/c of no back pressure or something and still would have misfires.

So i took the car into his buddy's exhaust shop and had a new cat put in. Got them to check the old cat and it was maybe only like 60 percent clogged. so it wasnt a clogged cat. The guy at the exhaust shop said they either work or they dont. So it wasnt the cat.

Still having the idle problem that the dealer couldnt figure out b/c they stated my car was "MODIFIED" b/c it had the GM S/C kit on it. that was the best they could do. It was the best they could do? i was so pissed!!! It's a GM performance part that was made for my car so tell me that one.

Anyhoots onto the rest of my own trouble shooting. Me and LafNgas couldnt figure out the problem b/c he said it's usually the cat converter that clugs up b/c the kit runs so righ. So he said the spark plug gap could be to big at .50 which the kit recommends. So I picked up another set of plugs and gapped them down to .30 as per his suggestion (same A/C Delco plugs). He suggested lower gap to prevent the spark from being blown out.

Car seems to run almost perfect at this point but still a little hesitation. So I picked up a new coil pack housing (you know the white thing) and four new little spark plug connector kits that attach to the housing. I got those replaced b/c the old boots looked pretty beat up and the housing was black in spots.

Car seems to be running pretty good now. No check engine light, but I cant tell if it's misfiring or not. I cant get a nice stretch of dry road to really hammer on it to Wide open throddle b/c it's winter now.

So here is the other problem with idle. Sometimes it just dips really low like down to 500rpm then back up say when pulling up to a light or driving in stop and go traffic. I have had it even stall on me the odd time when it bounces so low. I'm like WTF? it does this all the time.

I called GM and opened up a case with them. I explained how all this ordeal has cost me a sh*t load of money and I dont know if the issue is completely resolved yet. I told them that I wanted to speak to someone in the GM performance division. To find out if anyone is working on this issue. Even LafNgas is having the same problem with his car. Misfires and idles problems etc etc and many people on the .org

I explained to GM that why would the kit run perfect without a hitch for 10,000km then run like crap and have all these problems. I'm still having the idle problem and pretty sure that the misfire might still be there.

So at this time I'm waiting to find out if GM is working on the problem, maybe there might be a newer version of the reflash or if they can work on one to resolve this issue.

I paid $116 for 10 minutes worth of work when the dealer did the origional reflash. The dealer wanted to charge me again to bring in my car to see if there is a updated version of the software. They would have to bring in my car. Check the software version on my car then go online to find an update. I was like scr*w you!!!!!! why dont you do it for free since I paid you so much the last time. So that is what i'm complaining about with GM as well.

Maybe the GM part number from the kit is a old an older software version that they put on my car. Has the part number changed and there's a newer version? I dont know. that is also what I'm fighting with GM about to get them to resolve the issue.

So I'm starting this thread for people to post there issues with the GM S/C kit so I have some leverage with GM to let them know there is a problem with it.

So please post what you can. Sorry for the long storey.

Regards,

in reference to the m45 or the m62? Im assuming the m45 because you said 6 psi, if so Most people are having problems with the eco reflash.

any one do a compression test ?

sounds almost like ya popped a piston , i had that happen to me , as did a friend , but both of us smashed a plug

NeoJuice wrote:
-Did a compression test, All cylinders are good.

DID YOU ATTEMPT A RUNNING COMPRESSION TEST?

This article is refering to 2.4L S/C. But besides the point weither it is Eco or 2.4L we can still maybe do something here. Im fighting this with GM as high as I can go.

The Mechanic did a compression test on the motor. All is within spec.

a friend just had a compression test on his it was 190 , 180 , 200 , 190

but it still chunked a piston , both still run ok


other thing is to check the injector circuits , if everything in the ign had been check or replaced with good known working parts

This might help.



PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO

[quote=97cavie24ls(™)]a friend just had a compression test on his it was 190 , 180 , 200 , 190

but it still chunked a piston , both still run ok


other thing is to check the injector circuits , if everything in the ign had been check or replaced with good known working parts

Im assuming everything in the compression check turned out properly and was within spec.

The injectors have been tested and flow withing spec as the mechanic had checked. I dont know what you mean by circuits?

All ignition parts have been replaced. It probably has to do with the crappy GM reflash.

-MD- LD9 wrote:This might help.

How do I use this website? What will it tell me?

that website lets you check your ECU's calibration file and such. usefl for tuning.

have you check the MAP vacuum hose? a cracked hose can lead to poor idle as the MAP doesnt read right.

when was the last time you changed your O2 sensor? the first 02 sensor plays a big role in figuring out your fuel trims.

have you tried to reset your fuel trims yet? ive been told by disconnecting both battery terminal and holding them together for 5-10 seconds will reset your fuel trims. might help clear the problem up for now, but might come back.

make friends with some one with HPTuners and have them datalog your car. i orderd a tuner package from Tazmic (sp?) out in Alberta. maybe they tune aswell as resell the software and can do some data logging with you.



1997 RedR - ZedR

-Ill check my VIN number later on tonight on the website. Ill also check the S/C reflash part number in the part number box on the website as well.

-I replaced the Map sensor hose a while ago. But with the S/C kit I cant remember if it's a different hose now. Ill have to take a look at the engine compartment. I remember replacing it before getting boosted.

-I have never changed my 02 sensor on my car.

-I have never heard of the fuel trims thing before.

-My buddy scott (LafNgas) has a HP tuners.

Quote:

So here is the other problem with idle. Sometimes it just dips really low like down to 500rpm then back up say when pulling up to a light or driving in stop and go traffic. I have had it even stall on me the odd time when it bounces so low. I'm like WTF? it does this all the time.

mine does the same thing epically when the A/C is on, i believe that it is because there is a big accessory hanging off the front of the motor

and a cracked spark plug boot will make it run like sh!t cause the spark is arcing off the head, try getting the RK inserts, they help a bit as well

carey965,

Ill maybe look at getting the RK inserts. As I listed above in my origional post. The module, coils, new coil pack housing, and four spark plug boot kits have been replaced as well as a new Cat converter. So everything is brand new which might cause a problem.

I might try the other suggestion of maybe replacing my 02 sensor. It has never been changed as far as I know and there is 141,XXX KM on the car now. So I might try that.

I havent tried out the website yet as my VIN number is in my car on my insurance papers and I forgot to find the S/C part number from the instructions to enter it into that site listed above. But Ill do that today/tonight.

This post was meant so that people could post there troubles with the S/C kit no matter what kit it is for. The 2.4L or the Eco. Just to get GM to do something about the crappy reflash programming. I'm suprised other people havent posted any other information in this post. I'm hoping to pass this onto GM.

Regards,

you really think GM is going to do something for a platform that is dead?

personally, the GM reflash doesn't seem that bad. i would get the new 02 sensor cause like i said, it is used heavily in determining your AFR. even after reflashing my car with HPTuners, there was a period of about 2 weeks where i had a really rough idle. not sure why, but with my car having over 200 000 km on it, the intake or exhaust cam my be slightly off because the timing chain can stretch from use over time.

this is one reason why I'm contemplating cams and a new timing chain.



1997 RedR - ZedR

ya GM is not going to do too much about it, we are pretty much on our own

the reflash is crap, each vehicle is different but yet the reflash is still the same, my car runs rich as a pig i need to get hptuners run on my car

well, last week i had this EXACT problem and now my motors blown. Sputtered and everything and then at idle the timing chain snapped

carey965 wrote:ya GM is not going to do too much about it, we are pretty much on our own

the reflash is crap, each vehicle is different but yet the reflash is still the same, my car runs rich as a pig i need to get hptuners run on my car

Well I know the reflash programming doesnt seem to be any good. That is why i'm trying to find out from them maybe if there has been any revisions to the software.

I might try the new 02 sensor since the car is running pretty good at the moment but I still have the idle problem.

I hope that I can atleast get sometime done working my way up through GM.

Regards,

o2 sensor and fuel filter i would try. basic stuff first.

I change my fuel filter every 50,000km as recommended. I will look into the 02 sensor as i mentioned above.

I do not think your issue has anything to do with the GM reflash. You need to start doing your own work and stop taking your car to the stealership. I think you are beginning to see now how GM dealerships will blame a modified car for any problem you have even though it is a GM performance part. The GM mechanic that worked on your vehicle sounds like a joke to me.

Here is what I suggest you do. Do another compression test yourself. I would double check that as it may be possible you have a damaged piston. You might not know because you did not pull the original set of plugs yourself to see if gap was partially smashed shut. I know you said the mechanic said they were all fine but you did not see them yourself so you can't be sure.

A spark plug gap of .50 should be good. However Scott had the right idea by going to a smaller gap to see if the isue might have been sprark blowout. I would have gone down by .05 each time. .30 is more than likley to small and at only 6psi you would not be blowing spark out that bad unless you have a defective ignition part. Spark blowout would only cause a misfire when under full boost. It would not cause it to continue to misfire afterwards.


I have more to add but I will have to do so later as I am very busy at work.




FORGET GIRLS GONE WILD WE HAVE GOVERNMENT SPENDING GONE WILD!

Wade,

The GM tech I talked to seemed to know what he was doing. Didnt seem like a n00b and new his sh*t when I was talking to him.

Thanks for the input. The car runs pretty good now. The only issue i'm dealing with is the idle problem with it bouncing up/down the odd time. The car has had no problems with the .30 gap as far as I know, the roads are in to bad of a condition to try for WOT and full boost to test at this time.

Maybe the idle problem could be due to a partially defective 02 sensor in it not reading right. I figure that 7-8 years out of that part and it might be pretty well spent . I have never had changed it. Maybe it could be reading the fuel trims wrong like WhiteGoose said. But I can change that myself.

I only take my car into the dealer as a last resort...........believe me. I do everything myself.

All the ignition parts are new as I listed in my top post.

I read that about all new ignitionparts. I was having a hard time trying to see what issues you were still having.

The next part I was going to get to was about your bouncing idle. I had that same issue and I replaced my 02 sensor because I had a code for it at the time as well. That took care of my check engine light but had no effect on the bouncing idle. My bouncing idle was due to a bad TPS sensor. Along with that issue I would occasionaly have a hesitatuion when I hit the gas. I found out that you must unhook the battery and let the computer relearn the new tps sensor. I do not know exactly how long you have wait for it to clear the computer. I waited 20 minutes and that seemed sufficient.

Another issue you may be having is realted to the IAC moter. On the 2.4 they just do not seem to react quick enough to keep a smooth idle after abruptly letting off the gas. This would be why it sometimes idles down to low and almost or dies if you tap the gas. My car would do this when it was NA and when it was boosted. If your TPS senor is going bad this will make this issue far more noticable. I would definatly start with the TPS.Just from what you have described not to mention it is cheaper to replace than the 02 sensor.

The problem from to small of a gap would be a loss of power. You might not notice it at .30 If you gapped them at .25 I bet you would notice a difference in power. But regaurdless if you were not experiencing spark blowout changing the gap is pointless.

You are still using the stock size supercharger pulley right? You have not installed a water injection kit right? Let me know if you have done either one of those.



Edited 1 time(s). Last edited Thursday, December 13, 2007 2:01 PM


FORGET GIRLS GONE WILD WE HAVE GOVERNMENT SPENDING GONE WILD!

Wade,

I'm using the stock pulley, no water injection. Stock S/C setup.

I didnt know to small of a gap could cause loss of power. I gapped down b/c of misfires as per recommendations of LafNgas. It seems to have resolved the issue for now. Only difference I can tell with the smaller gap is a very very very slight rougher idle and maybe a slight loss in power but I cant really tell right now b/c the roads are all covered in snow. All I do is slip and tires spin.

I was going to wait until spring to probably play around with the gap to see if I could get it back up to .50 without misfires. But since it's winter now and to cold out im not going to mess with it. Technically it should run fine on .50 like it did before. I will try it again once it warms up.

Iac motor? I think I replaced that a while ago before boosting. As you mention in your post above I do recall my car doing that a little when NA. I will check out the price of a new TPS sensor. and try and get that replaced this weekend.

As far as I can tell I havent had any problems with my 02 sensor in the car. But since it's 7 years old. Who knows. That other member above mentioned something about it reading the fuel trims properly.

Did the TPS resolve your issue? or could it just be the IAC not reacting fast enough.

My issue was definalty TPS related. Changing it fixed the bouncing idle and slight hesitation. I bought the tps from the local autopart store. If I remember right is was only 35 bucks. Just make sure you unhook the battery while replacing it so that when it starts back up it relearns the new tps sensor otherwise you will have a high idle for no explainable reson. Without a good tps sensor the iac moter has a harder time doing its job corectly.

The reason I asked about the what pulley you are using is because obviously the more boost the more likely it is you are blowing out spark. The reason I asked about the alky injection was because if you do install it be sure to locate the sprayer after the throttle body. Most people use a throttle body spacer to tap the sprayer nozzle into so the alky mix is injected after the tps sensor. Tps sensors do not like getting wet inside.



FORGET GIRLS GONE WILD WE HAVE GOVERNMENT SPENDING GONE WILD!