CobaltCoupeCrazy

iTrader: (1)

OK guys,

I have a 2005 5-spd LS coupe. While under warranty I had lots of miscellaneous issues addressed and corrected. Just before 36,000 miles my car lost a coil. The '05's had two coils. I was driving along one Sunday afternoon, made a turn, got on the gas and bam, no warning, no sign, no anything I just suddenly lost two cylinders. When it first happened I wasn't exactly sure what it was; the car lost power and sounded like a flat four with exhaust (duh duh duh duh that sound). I took the car by Advance on the way home and when the guy said, "where are the wires; it has to have wires!!", I just hoped in a drove home. I had previously purchased but not yet installed the Nology Hotwires kit. I thought I'd go home and hook it up to see if the problem would go away. Hooked up the kit and it went away, so I knew I had a bad coil. Took it to the dealer and they said yes, I had a bad coil and they replaced the coil pack assembly. I shortly thereafter permanently installed the Hotwires kit and kept my replacement OE coil pack unit close by. I had changed plugs but never had any problems with the car after that, UNTIL NOW.

The other night on my way home from work I was sitting at a light when it sounded like someone's car was having trouble. I realized my car was the one making the noise; I revved up and out came a puff of black smoke. I experienced the same duh duh duh duh sound but couldn't tell much of a difference in power, so I thought I might have just had a problem with one cylinder. I came home switched out plugs and the coils, but found no fix. Took it to the dealer and they said they couldn't come up with anything b/c the tech 2 didn't come up with anything or detect any misfires. They retrieved the following codes: PO300, PO341 and PO455-Random Misfire. Camshaft position sensor fault and evap system leak. OK, evap system leak is most likely my fuel cap b/c my car always says check fuel cap; it was replaced under warranty but started again in a few weeks. The tech guy says my car does not have a camshaft position sensor (it's a dummy ciruit), it actually only has a crankshaft position sensor and if it was bad, no cylinder would fire. I thought that it had to be a plug not firing or an injector not working, but the tech two didn't detect any problems.
What else might cause this problem?? I'm totally lost, missed a day of work yesterday and got a bunch of crap from my boss about it. The car drives good, but sounds like crap; sounds like it's missing a cylinder but it seems to drive smooth, as it also did on two cylinders. Could I have a hole in something somewhere causing the sound?? something with the cat or resonator?? It sounds exactly the same way, but to a lesser extent as it did when I lost the two cylinders due to the bad coil.

PLEASE HELP!! Thanks in advance, Scott

jlong3382

I'm not going to try to fool you, I just got my Cobalt in January and havn't had a problem yet, so I havn't really learned much about the car. However my last car was very different. It was a '02 Grand Prix GT that I slapped a turbo kit on myself without really knowing WTF I was getting into. I had a bunch of EVAP and electrical problems, but I just disabled the EVAP DTC's, so the light would stay off. When the Grand Prix ran right, it was a 12.4s car. When it didn't run right it was a real BITCH, but I loved it. The one thing that car taught me was that dealership service techs will HATE you, and even flat out lie to you, if you take your mod'd car to them to troubleshoot a problem. Sorry for ranting, but I don't trust dealerships anymore. Good luck with your problem.

RedBaseBolt

Post this in the problems section, you'll get more responses.

If you are missfiring trying changing your plugs, changing your gas station and resetting the engine by pulling power to the battery for 10 mins, it might help.

YellowLT

This sounds like the same thing that happened to me. I thought I had a Bad Coil Pak, After replacing the Coil Pack it did the same thing. It turned out to be the ICM. Replaced that and everything is golden now

PS Do you have a link to your Hot Wires Kit.

blackjack hotrods

Maybe it's this??


#PIP3433D: SES Light and Sever Engine Misfire On Cylinder 1 And 4 or Cylinders 2 And 3 - keywords ICM ignition miss module no P0300 P0301 P0302 P0303 P0304 plug repeat replacement spark - (Jul 24, 2007)

Subject: SES Light and Severe Engine Misfire on Cylinders 1 and 4 or Cylinders 2 and 3


Models: 2002-2005 Chevrolet Cavalier

2005-2006 Chevrolet Cobalt

2006-2006 Chevrolet HHR

2004-2006 Chevrolet Malibu

2004-2005 Chevrolet Malibu Classic

2002-2004 Oldsmobile Alero

2007 Pontiac G5

2002-2005 Pontiac Grand Am

2005-2006 Pontiac Pursuit (Canada Only)

2002-2005 Pontiac Sunfire

2003-2006 Saturn Ion

2004-2005 Saturn L Series

2002-2006 Saturn Vue

with 2.2L Engine (VIN D or F - RPO L61)




--------------------------------------------------------------------------------

This PI Supercedes To Remove 2007 Model Year. Please Discard PIP3433C


--------------------------------------------------------------------------------

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Some customers may comment on a severe engine misfire and a SES Light. Upon inspection, DTCs P0300 - P0304 may be found due to misfires on cylinders 1 and 4 or cylinders 2 and 3.

Recommendation/Instructions:
If this concern is encountered, inspect circuits 406 (IC Control for 2/3 Coil) and 423 (IC Control for 1/4 Coil) for an intermittent short to ground or poor connection on either end. Depending on the model, these circuits may short on the AC lines near the AC compressor, on the transmission mount, or on the transmission lines where they enter the transmission. If there is no problem found with these circuits, inspect the ignition control module ground to ensure that it is clean and tight.

If there is no problem found after performing the suggestions above and the SI diagnostics lead to ignition module replacement, replace the ignition module as directed but also replace all of the spark plugs and clean the ignition module ground to possibly prevent future ignition module damage.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION


Š 2008 General Motors Corporation. All rights reserved.

CobaltCoupeCrazy

iTrader: (1)

The HOTWIRES kit was discontinued and I bought it from an online retailer at a super deal on closeout.

There is no misfire causing the problem. I pulled off the coil pack assembly, put in four plugs (leaving the one's in the head) and grounded the plugs against the valve cover. When someone turned the key, I could see all four plugs sparking. The four plugs used for a visual test are the four plugs that were in the car when the problem started.

I myself also thought that it was probably the ICM, but it isn't listed in the parts department as an Ignition Control Module, but something has to be in control!! Also, since I am seeing a spark at all four plugs I don't think that is my problem. The problem is not random or intermittent, it is constant. I thought maybe I was getting spark but no fuel, but I'm sure that would show up on the Tech 2, would it not??

How do I MOVE this to the problems section?? I don't want to double post.

blakjack hotrods,

Wouldn't that cause a problem with two of the cylinders and not just one?? I know for sure I'm not losing power from two cylinders; I'll never forget what that feels and sounds like. I did think that it could be an ignition control problem where I see that all plugs fire but perhaps one plug is firing at the wrong time. If I had constant unburned fuel going out of the exhaust I should throw a code for emissions or no?? They drove the car with the Tech 2 and came up with nothing!! They hear the noise but that's not a skip and I'm going, well, it's a dead cylinder due to something. They say if the computer doesn't pick up any other codes or problems they won't know what to do to fix it or what parts to check.
I'm really lost at this point and they don't seem to care or even enthused to try and figure out what it is. At $82 an hour and a customer's request I figured they'd be willing to spend hours working on just trying to find something but they pretty much told me it was pointless.

blackjack hotrods

yes it would cause a problem with two cylinders since on e coil runs 2 cyls. It's hard for a dealership because, contrary to popular belief, they don't want to waste your money.

Here is a description of the Cam Sensor from the diag sheet for code P0341:
This ignition system does not use a conventional camshaft position (CMP) sensor that detects valve train position. The ignition control module (ICM) detects when #1 or #3 cylinder has fired on the compression stroke using sensing circuitry integrated within each coil. The sensing circuit detects the polarity and the strength of the secondary voltage output. The higher output is always at the event cylinder. The ICM sends a CMP signal to the engine control module (ECM) based on the voltage difference between the event and waste cylinder firing energy. This system is called compression sense ignition. By monitoring the CMP and crankshaft position (CKP) signals, the ECM can accurately sequence the fuel injectors. If the ECM receives an intermittent CMP signal from the ICM, DTC P0341 sets.

So it's possible that the wires for your ICM are shorting and sending false signals for the CMP reference causing incorrect injector timing/pulses, which could cause your black puff of smoke. As hard as it is to diagnose a problem in person, its about a hundred times more difficult over a forum. I would hope that the techs at the dealership would use all of their resources and find these bulletins on their own but you can never tell. The evap code is probably not related to your current problem at all, by-the-way.

CobaltCoupeCrazy

iTrader: (1)

OK, I'll check to see if I can find any problems with the wires. I don't think the people at the dealership looked up anything (my first thought was to check for bulletins). Apparently my fuel cap is bad, again and is causing the evap code.

Thanks to each of you for your input. Can anyone tell me how to MOVE my thread to the Problems section??

Well, the wires seem to be very well contained; I couldn't see any problem with the exposed wires. I did disconnect and reconnect the battery after about 2 hrs and still, the same problem.

CobaltCoupeCrazy

iTrader: (1)

BUMP

Tomorrow I'm gonna try to listen all over and see if I can come up with anything; I'll try to make sure that it's nothing in the exhaust. Once I reconnected the battery, I drove around quite a bit and the CEL has yet to come back on (usually by the second day it comes on b/c of the fuel cap).

CobaltCoupeCrazy

iTrader: (1)

Well, I took off the SS OE catalytic converter and put on the LS cat. No difference, well, except it's not as loud. Could it possibly be the gasket b/n the head and exhaust manifold?? After installing the SS exhaust manifold and downpipe I would always hear a raspy buzzing sound when the car was cold, but it would go away once the car warmed up. I no longer hear that sound. I was wondering if perhaps it was a gasket vibrating that swole up once it got hot and then stopped. Now I'm wondering if it could be that the gasket has break in it and instead of vibrating it is moving more (flapping) and causing this pulsating (chop) sound in my exhaust.

Any ideas, anyone??

umrdyldo

iTrader: (1)

i have the same sound as you but I have SS manifold and ZZP downpipe. Not sure if it's normal or like you said something with the gaskets.

BLKLS

dude i have been in and around the car buisness for sometime now and have NEVER, NEVER, meet someone who will lie to you. thats just wrong, yes aftermarket parts can make diagnosing somthing harder sometimes, butif someone lies to you about what you installed then they are a crappy person flat out.



from blackjack hotrods last post, this info would lead me to try an icm, hell if you know someone near you with an 05 maybe you could just swap them real fast and take it for a ride see if it goes away. just check the wiring first again real good so incase it is shorting out it won't harm the other icm.

CobaltCoupeCrazy

iTrader: (1)

Well, I've checked to make sure all 4 plugs fire and they do; visual check. No misfires showed up on the Tech II. I don't seem to have any noticeable reduction in power or fuel mileage. I am gonna remove the exhaust manifold and check that gasker and then when putting it back on I will re-install the SS downpipe. I can no longer hear the buzzing raspy sound that I used to hear when the car was cold. It may not be making the noise anymore or I just can't notice it over the new noise (I would think I could still hear it). I never heard the buzzing raspy sound until I switched to the SS manifold and downpipe. I never heard the noise once things warmed up and now I have this other noise. I was thinking it was a buzzing gasket when the car was cold that would quit vibrating after warming up and now it could possibly be broken on the inside without causing a leak to the outside.