2008 Suburban misfire cylinder 1

[Cullen]

Hi All-

Hoping to get some help getting my suburban running again.

I have a Misfire code for cylinder 1. Its running rough and i have the Stablitrack and traction control warnings as well.

What i have done:

- swap plugs for 1 and 3 with no change
- swap plug wires for 1 and 3 with no change
- swap coil packs for 1 and 3 with no change
- swap injectors for 1 and 3 with no change.

where do i go from here?

the plug from cylinder 1 was very clean but also had oil on it, smelled of unburned fuel.

from what i have read the stabilitrack and traction control issues are caused by the misfire?? is that correct?

Thanks-

[muddkatt]

Not enough information, need engine, miles on engine, when last tune up was, by swapping components , how did you ensure the misfire was still on #1?

[Cullen]

Sorry. I'll fill in some more details. Its a 5.3l Suburban LS 1500. 4x2. About 95k miles on it. Not sure when the last tune up was, i bought about a year and this is the first issue i've had with it. Its always had an evap code, but ran strong. It has consistently used about quart of oil per 2000 miles.

 

after swapping each of the components i cleared the codes with EASE scan tool software running on my laptop. the Code for #1 misfire kept coming back and i could also see the misfire in the live reading.

 

I live in Panama and the mechanics here are for the most part no good. I took the suburban to one for a noisy lifter on the even bank and when it came back the lifter was quite but now had the misfire on #1.

[muddkatt]

I would start by checking the compression on #1. If its less than 140 psi, check the compression on all cylinders. Using a quart every 2000 miles is high in my opinion, but the AFM engines are known to use oil more than the older engines.

[SilverSulley]

It could also be an issue with that cylinder's coil.

[muddkatt]

It could also be an issue with that cylinder's coil.

OP said he swapped the coil with #3 and it did not correct the problem.

[SilverSulley]

Sorry! I blame Monday for the oversight, but I agree that you should check your compression then. You've covered ignition system, fuel system (you could also check fuel pressure - might be running lean) and now the engine components. A worn lobe could also be the culprit but hard to say until you compare against the other cylinders...

[Cullen]

Thanks for the replies everyone. still trying to get the only mechanic with a pressure gauge to come out and do the compression test. Hopefully tomorrow....

[Cullen]

Found the problem.

 

https://gyazo.com/229cef6ad6c4f4b0cfab70fab6f44bf4

 

now to figure out why.

[muddkatt]

Found the problem.

 

https://gyazo.com/229cef6ad6c4f4b0cfab70fab6f44bf4

 

now to figure out why.

 

That will cause no/low compression and a misfire. I have seen before that just replacing the push rod corrected the problem long term. However it could be a bad lifter or cam lobe that caused the problem and the bent push rod is the result.