Misfire issue

[onedoughboy]

So you have a 2006 Cobalt 2.2l with 57k, with a miss on 1 & 3, you changed plugs, you swapped injectors, you replaced the coil pack, and verified compression.

How long have you owned it? When did it start missing?

Was the coil pack new or used. Could be two bad ones, seems not likely. There is a ground wire on the transmission about level with the starter, on a bell housing bolt, that is known to become corroded, but the miss fire would be random.

 

[maverickdog8]

So you have a 2006 Cobalt 2.2l with 57k, with a miss on 1 & 3, you changed plugs, you swapped injectors, you replaced the coil pack, and verified compression.

How long have you owned it? When did it start missing?

Was the coil pack new or used. Could be two bad ones, seems not likely. There is a ground wire on the transmission about level with the starter, on a bell housing bolt, that is known to become corroded, but the miss fire would be random.

The coil pack is brand new from my work(Oreillys). I got the car with 49k miles on it from my grand parents who were going to scrap it due to the ignition recall(they were scared). The miss started at about 53k.

 

[onedoughboy]

I reread the entire thread, in your first post you stated that the car shuts off after 30 minutes. Is it always 30 minutes? Do you have any codes that are U1000? Do you live in a wet area, by salt water? Has the car been in an accident? Flood? There is a piece to this puzzle that is missing. Who would scrap a car that has 49k because a recall... These cars are simple in design. I'm still thinking ground wire on transmission, or timing. But a broken wire, corrosion in a connector, loose connection, intake gasket leak or vacuum leak, could also be causing this. I once had a cobalt that would quit once in while, while driving down the road, turned out to be corrosion inside the main fuse box. I figured maybe someone liked to power wash the engine compartment to much.

 

[maverickdog8]

I reread the entire thread, in your first post you stated that the car shuts off after 30 minutes. Is it always 30 minutes? Do you have any codes that are U1000? Do you live in a wet area, by salt water? Has the car been in an accident? Flood? There is a piece to this puzzle that is missing. Who would scrap a car that has 49k because a recall... These cars are simple in design. I'm still thinking ground wire on transmission, or timing. But a broken wire, corrosion in a connector, loose connection, intake gasket leak or vacuum leak, could also be causing this. I once had a cobalt that would quit once in while, while driving down the road, turned out to be corrosion inside the main fuse box. I figured maybe someone liked to power wash the engine compartment to much.

Its not always 30 minutes. Sometimes it doesn't do it at all. I have a random misfire code that pops up from time to time, but not constant. I live in Iowa so no saltwater. Where is the ground strap located? My grandparents owned the car and when I got it, it looked like it had never been washed Lol.

 

[onedoughboy]

There's a large ground wire located under the driver sides side headlight, you have to remove the headlight and the headlight bucket. Follow it back to the transmission, there it connects to the grounds that are known to be a problem on a bell housing bolt. There's about seven or eight ground wires, the connector is known to become corroded. Causing no starts, stalls, and random misfires. So other odd problems.

 

[maverickdog8]

So I swapped out that ground. Drove the car for about 45 minutes and have no misfire. I'm hoping it was just a corroded wire.

 

[maverickdog8]

Well after driving all around yesterday and not having the engine light come on or the car misfire at all, I'm going to call the issue cured. I still have the hatred for the car, but now its because I spent a chunk of money on issue that was a $3 fix. Lol. Now time to go back to audio things.

 

[maverickdog8]

Surprise surprise. The misfire i swore i cured came back about a week ago. Worse than the 1st time. I really need a permanent fix for this. Its middle of winter and i dont have a garage to work on this thing in constantly. Anyone have any ideas?

 

[YelloEye]

Check the $3 fix over again. Plugs.

 

[maverickdog8]

The $3 fix is what im going to do, but i dont want to have to keep doing it every few months.

 

[maverickdog8]

More misfire issues

I replaced the ground again last week. Go to drive the car this morning and now I have 2 codes again. P0171 and P0300. The car is freaking out and the engine light is flashing. The plugs, coil pack, icm, and plug boots are all new within the last 5k miles. I have checked compression even and it all checks out. This car is my daily driver, so I can't have it constantly doing this.

Driving on the interstate the car misses and stutters when im up around 2500-3000 rpms. Stutters going up hills or on flat ground. This is a reoccurring issue and I feel like its never going to go away.

 

[YelloEye]

P0171 is an air fuel lean code. You could clean your MAF sensor with MAF cleaner.

I'll look at my books when I get a chance, I just reformatted my computer and haven't installed that program yet.

 

[YelloEye]

Here's the trouble code info http://filebin.ca/1rSv0T33qJE5/P0171.pdf

 

[maverickdog8]

Now here is the real kicker. I filled the tank from 1/4 and the misfire went away completely. I feel like I am getting this issue only when fuel is under 1/2. I put in 2 bottles of heat to treat for possible water and will check back from that.

 

[YelloEye]

Odd. You could drop and drain the tank.

Merged threads for continuity.