2008 Chev Malibu 2.4 stumbling/stalling

[SatinSilver]

Originally Posted by irv
I will try what you suggest just the same to eliminate that possibility but I also don't think that is the problem?


irv,

The previous owner(s) could have used a heavy set of keys while operating the car thus weakening the ignition cylinder. Esp if that part is prone to issues. Good luck and hope you get it sorted for your son. It seems like he just got that car not long ago.

 

[dishdude]

I don't think an ignition switch would make the engine miss like shown in the video. I'm leaning towards loose or damaged wiring.

 

[addyguy]

Timing chain wear causing timing to be off?

These engines have issues with oil burning, low oil levels, and timing chain wear from it.

Does he keep the oil topped off, or let it go low?

 

[irv]

Originally Posted by SatinSilver
Originally Posted by irv
I will try what you suggest just the same to eliminate that possibility but I also don't think that is the problem?


irv,

The previous owner(s) could have used a heavy set of keys while operating the car thus weakening the ignition cylinder. Esp if that part is prone to issues. Good luck and hope you get it sorted for your son. It seems like he just got that car not long ago.

Thanks SS. He is home now so I will go try that soon.

Originally Posted by dishdude
I don't think an ignition switch would make the engine miss like shown in the video. I'm leaning towards loose or damaged wiring.


My thoughts as well. A chaffed wire somewhere that picks up moisture when it rains or is washed.

Originally Posted by addyguy
Timing chain wear causing timing to be off?

These engines have issues with oil burning, low oil levels, and timing chain wear from it.

Does he keep the oil topped off, or let it go low?


The timing chain and tensioner was done back in 2014. The car has been great on oil with zero consumption issues to date despite him putting on over 20 K (kms) since we got it last August.

Thanks guys

 

[irv]

Originally Posted by SatinSilver
Originally Posted by irv
I will try what you suggest just the same to eliminate that possibility but I also don't think that is the problem?


irv,

The previous owner(s) could have used a heavy set of keys while operating the car thus weakening the ignition cylinder. Esp if that part is prone to issues. Good luck and hope you get it sorted for your son. It seems like he just got that car not long ago.

No luck, SS. The key is pretty solid in there and there was no signs of a stumble or stall when I moved the key around a bunch of times up and down and back and forth a bit.
Suppose to rain tomorrow so we'll see what happens?

 

[clinebarger]

Originally Posted by irv
Originally Posted by clinebarger
Ignition Switches are a known failure point on these cars.

*With the car idling in park.....Put pressure on the key Up & Down (Vertically) & see if the engine stalls, Do not rotate the key in the cylinder. This doesn't alway cull a bad ignition switch, But worth a try.

*The second way is too remove the Knee Bolster & remove the Ignition Switch & Key Cylinder assembly from the Dash Carrier.....Let it hang down & wiggle the electrical connector with the engine running.

*In a perfect world......I would recommend a "Graphing Multimeter with logging capability" so you can record/log any power drop-outs on the ignition switch output circuits.
You could simply use a Test Light or Multimeter......But the drop-out could be for fractions of a second & it can be dangerous trying to pay attention to test equipment while driving.

You could always just throw a new switch at it, I hate doing that myself.


My wife was able to do some digging at work yesterday (works in GM office) and was informed the 08 Malibu's were not part of the ignition switch recall/update. I will try what you suggest just the same to eliminate that possibility but I also don't think that is the problem?

Of course my son's car ran perfect this morning with no signs of a stumble or a stall. The real test will be after another rain or wash. Fingers crossed here that what I did yesterday helped/stopped the condition but I am not holding my breath.

Thanks for the info.

I missed the misfire part of the symptoms.

GM Ignition Switch failures go way deeper than the recall, The recall centered around the the switch being turned to accessory unintentionally, The failure mode I'm talking about is centered around Worn, Dirty, & Burnt Contacts in the switch that can cause intermittent opens in the Ignition 1 circuit.

 

[irv]

Originally Posted by clinebarger
Originally Posted by irv
Originally Posted by clinebarger
Ignition Switches are a known failure point on these cars.

*With the car idling in park.....Put pressure on the key Up & Down (Vertically) & see if the engine stalls, Do not rotate the key in the cylinder. This doesn't alway cull a bad ignition switch, But worth a try.

*The second way is too remove the Knee Bolster & remove the Ignition Switch & Key Cylinder assembly from the Dash Carrier.....Let it hang down & wiggle the electrical connector with the engine running.

*In a perfect world......I would recommend a "Graphing Multimeter with logging capability" so you can record/log any power drop-outs on the ignition switch output circuits.
You could simply use a Test Light or Multimeter......But the drop-out could be for fractions of a second & it can be dangerous trying to pay attention to test equipment while driving.

You could always just throw a new switch at it, I hate doing that myself.


My wife was able to do some digging at work yesterday (works in GM office) and was informed the 08 Malibu's were not part of the ignition switch recall/update. I will try what you suggest just the same to eliminate that possibility but I also don't think that is the problem?

Of course my son's car ran perfect this morning with no signs of a stumble or a stall. The real test will be after another rain or wash. Fingers crossed here that what I did yesterday helped/stopped the condition but I am not holding my breath.

Thanks for the info.

I missed the misfire part of the symptoms.

GM Ignition Switch failures go way deeper than the recall, The recall centered around the the switch being turned to accessory unintentionally, The failure mode I'm talking about is centered around Worn, Dirty, & Burnt Contacts in the switch that can cause intermittent opens in the Ignition 1 circuit.


I just took it for a 15 minute test drive in the rain. No stumble or hints of stalling at all. My son is getting his wisdom teeth out at 3:10 (poor kid!) so I will take the car with when I drive him to his appointment.

I honestly don't think this is an ignition problem but rather a wire/moisture problem? The drive today is inconclusive as it doesn't always do it so I won't be a 100% comfortable until it doesn't happen for a week and that is only if we get more rain or after a few washes.

What a pain in the butt!

 

[irv]

Just got back from a test drive and sure enough, it happened again!

It is windy this morning but the sun is out and it is somewhat warm. I am unsure when the rain ended last night but I knew this would be a good test for it. It started and ran great for the first 5-10 minutes then the stumble happened. It never stalled but was very close to.

Once the stumbling stops, it tunes right up and runs great just like any car would so, imo, it is a moisture problem.

It has been suggested to me a few times now that it might be the crank sensor so I may as well replace it and keep my fingers crossed. I don't want to start throwing parts at it but this will give me an opportunity to clean all the wires/cables that go to the starter and whatever else I can find under there.

During some reading on a Malibu site, some have replaced the fuse block/box under the hood. My son's looks to be in great shape when I remove the cover but that doesn't let me see underneath it.
Any idea if there is much to removing it and what is underneath?

 

[Popsy]

Another thing that happened to me on a Renault engine with coils on plug, symptoms were similar, stumbling with occasionally dashboard shortly illuminating like a Christmas tree.
We searched for a while, turned out one of the coil was sometimes shorting and "sending back" (does it make sense ?) the wannabe spark into the main harness, creating havoc with ECM.

Can you have access to a scanner with logging capabilities ? Could give you an idea of what's happening when it stumbles.

 

[irv]

Originally Posted by Popsy
Another thing that happened to me on a Renault engine with coils on plug, symptoms were similar, stumbling with occasionally dashboard shortly illuminating like a Christmas tree.
We searched for a while, turned out one of the coil was sometimes shorting and "sending back" (does it make sense ?) the wannabe spark into the main harness, creating havoc with ECM.

Can you have access to a scanner with logging capabilities ? Could give you an idea of what's happening when it stumbles.



I removed the black plastic engine cover yesterday but could not get the car to run without it. I was hoping to spray the coils with a mist of water but because of the MAF, likely, and another hose that attaches to the cover, the engine would not run.

I removed all 4 coil plug connectors to inspect them then applied some dielectric grease to all of them. Looked around further for something obvious, taped some wires here and there, etc, and that was about it. Like I previously mentioned, it was bone dry under that black cover so there is no way they are getting wet.

Would it be normal, if it was a coil, for the car to start up and run fine for 5 to 10 minutes then all of a sudden start acting up? Not to put thoughts into anyone's head, but my gut tells me if it was a bad/damp coil, it would struggle to start and struggle to keep running initially, not after?

Edit: I have no access to a scanner with logging capabilities.

 

[Popsy]

Normal I don't know, but in the case of the Renault car, it was working perfectly fine, revving all the way to redline, making normal power, etc, then for a few seconds you had nothing, then power again, etc.

Keep in mind the affected coil was defective in its design (there was a recall on them, but apparently the replacement model was also somewhat defective), on these engines the coils are very small and apparently gets very hot, internal insulation tends to melt and create occasional shorts.
We searched for a while, changed crank sensor, even tried a replacement ECM (with the programming necessary...) since wiring seemed ok, finally tried some coils from another engine, and that was it. A $30 part made us spent like a month (working weekends) going crazy.

Not saying it's a coil in your case cause I don't know, but hey it could be

It could also be a cold joint somewhere.

 

[irv]

Originally Posted by Popsy
Normal I don't know, but in the case of the Renault car, it was working perfectly fine, revving all the way to redline, making normal power, etc, then for a few seconds you had nothing, then power again, etc.

Keep in mind the affected coil was defective in its design (there was a recall on them, but apparently the replacement model was also somewhat defective), on these engines the coils are very small and apparently gets very hot, internal insulation tends to melt and create occasional shorts.
We searched for a while, changed crank sensor, even tried a replacement ECM (with the programming necessary...) since wiring seemed ok, finally tried some coils from another engine, and that was it. A $30 part made us spent like a month (working weekends) going crazy.

Not saying it's a coil in your case cause I don't know, but hey it could be

It could also be a cold joint somewhere.



I honestly don't think, but could be wrong, that if it were a bad coil, the car would still run on 3 cycl's?

When you say cold joint, are you referring to a split/chafed wire somewhere or something else?

 

[mightymousetech]

Originally Posted by irv
My son's 2008 2.4 Chevy Malibu stumbles and outright stalls on him sometimes, especially after/during a rain or washing his car. I have replaced the plugs and shortly afterwards, it stalled on me less than 100 yrds away.

I have looked at electrical connections, the battery, fuses, etc, under the hood but all seems good?

Something, imo, is definitely getting wet/damp which is causing this.
He washed the car Saturday, took it for a quick drive after, then yesterday, after driving home from work, (it was fine on his way to work) it stumbled on him again. He video'd it this time and it sounds like it is running on 2-3 cylinders. I took it for a drive immediately after and it ran great???

The car doesn't throw any codes either.

Has anyone else came across this before, and if so, what did you discover?

It's getting frustrating to say the least, and of course, my son is nervous to drive it.

Thanks in advance.

Sounds like moisture may be getting on the MAF. Don't suppose he installed some kind of intake system?

 

[irv]

Originally Posted by mightymousetech
Originally Posted by irv
My son's 2008 2.4 Chevy Malibu stumbles and outright stalls on him sometimes, especially after/during a rain or washing his car. I have replaced the plugs and shortly afterwards, it stalled on me less than 100 yrds away.

I have looked at electrical connections, the battery, fuses, etc, under the hood but all seems good?

Something, imo, is definitely getting wet/damp which is causing this.
He washed the car Saturday, took it for a quick drive after, then yesterday, after driving home from work, (it was fine on his way to work) it stumbled on him again. He video'd it this time and it sounds like it is running on 2-3 cylinders. I took it for a drive immediately after and it ran great???

The car doesn't throw any codes either.

Has anyone else came across this before, and if so, what did you discover?

It's getting frustrating to say the least, and of course, my son is nervous to drive it.

Thanks in advance.

Sounds like moisture may be getting on the MAF. Don't suppose he installed some kind of intake system?


I have cleaned the MAF twice and both times it looked clean/great with no evidence of water. I also put dielectric on the connector. The car has zero mods done to it.

 

[Popsy]

Originally Posted by irv


I honestly don't think, but could be wrong, that if it were a bad coil, the car would still run on 3 cycl's?

When you say cold joint, are you referring to a split/chafed wire somewhere or something else?

If the coil goes bad, yes.

In my case (just referring to what happened to me lol) the coil wasn't "bad" per se (as not producing high voltage anymore), just sometimes internally shorting, I guess (not really sure how a coil works) shorting the high voltage side to low voltage side, which was temporarily confusing the ECM when the tension spike was happening. The problem was also worse with humidity (Brittany, humidity is almost always high) and heat.

Cold solder joint, usually in one of the electronic units ? Could be anywhere, really wild guess here. Could also be a chaffed wire somewhere...it's difficult to pinpoint. If you've checked all the major electrical connection, plugged/unplugged the ECM several times to remove any eventual corrosion, then I don't know what else to do, except data logging.
If you have a scanner with live data capability, maybe you can try to have someone driving while you look at it and pray problem happens to spot any off chart data at that moment ?

Also I don't remember, did you change the spark plugs, or just inspect them?

 

[irv]

Originally Posted by Popsy
Originally Posted by irv


I honestly don't think, but could be wrong, that if it were a bad coil, the car would still run on 3 cycl's?

When you say cold joint, are you referring to a split/chafed wire somewhere or something else?

If the coil goes bad, yes.

In my case (just referring to what happened to me lol) the coil wasn't "bad" per se (as not producing high voltage anymore), just sometimes internally shorting, I guess (not really sure how a coil works) shorting the high voltage side to low voltage side, which was temporarily confusing the ECM when the tension spike was happening. The problem was also worse with humidity (Brittany, humidity is almost always high) and heat.

Cold solder joint, usually in one of the electronic units ? Could be anywhere, really wild guess here. Could also be a chaffed wire somewhere...it's difficult to pinpoint. If you've checked all the major electrical connection, plugged/unplugged the ECM several times to remove any eventual corrosion, then I don't know what else to do, except data logging.
If you have a scanner with live data capability, maybe you can try to have someone driving while you look at it and pray problem happens to spot any off chart data at that moment ?

Also I don't remember, did you change the spark plugs, or just inspect them?


I replaced the plugs with new ones. If I had to guess, I'd say this car still had the originals in it?

Furthering my thinking here, can a dirty or defective throttle body and/or its electronics maybe cause this problem? I just came back from another test drive and when the car was barely warm, it stumbled on me as I was leaving a stop sign. It didn't stall, just a stumble like it was going to then ran great.
When I have had his engine cover off, I have noticed some soot built up down in there. The procedure for cleaning one is just to use a rag with the product on it, (no direct spray) but that would only clean the front side of it, not behind the throttle plate. I assume anything is better than nothing but will this really do anything?
To remove it and clean both sides, I have read where the computer will have to relearn everything but the only, proper way, to do that is to have a dealership do it for you?
I know I am drawing at straws, but, imo, it is something to consider??

 

[Popsy]

I honestly don't know, but unless it's sensor related (MAF/MAP ?), I don't see a dirty throttle body making the engine stumble only from times to time.

 

[irv]

Originally Posted by Popsy
I honestly don't know, but unless it's sensor related (MAF/MAP ?), I don't see a dirty throttle body making the engine stumble only from times to time.


I just tried what this guy does in this vid and my son's car stayed running, it didn't quit. Is this conclusive that the MAF is defective or is it just maybe different on different cars?

 

[dishdude]

If the visual inspection turned nothing up, you need to find a way to obtain a scanner that shows live data. Anything else is just a guess.

 

[irv]

Originally Posted by dishdude
If the visual inspection turned nothing up, you need to find a way to obtain a scanner that shows live data. Anything else is just a guess.


Yes, I believe you're right. I was hoping, after watching this vid that someone directed me to, that I had found my problem but doing some further reading, it sounds like not all cars will quit running after one unplugs the MAF sensor.

Thanks