Any Chevy Techs out there

[Andy Greene]

I have - wifes - 2011 Chevy Cruze 1.8l that has developed a misfire at idle and on accel - flashing mil and tcs light -

Changed the leaking VC gasket - 3 plug wells where full of oil- and the plugs. But it still has a flashing mil and tcs light.

Any suggestions ?? Still has a miss at idle _ dead hole miss - till its over 2000rpm and cleans up. cleans up off load ( neutral) also.

 

[Steve Seebold]

Does it have individual ignition coils for each cylinder or one coil for everything? With individual coils you could have a dead one.

 

[Andy Greene]

One in line type pack - no way to swap one and see if I can move the problem so to speak-

 

[Mike Byer]

Can you read the p codes? Should have some in the 300 range for the misfire. I don't do Chevy, but a car is just a car.

 

[dave roach]

Andy

I was a GM tech for 25 years and retired 16 Years ago.

The service traction control light is on.

On the miss fire I would say you have a bad coil.

Need to take it to auto zone and have them to run the codes.

Dave Roach

 

[Daniel's Racing]

It may need the coil even if it doesn't fix the issue. The multi cylinder coil packs from most manufacturers break down after some road time.

Even with the trouble codes it often takes skill to determine cause without changing parts you may not need. Access to data bases they have today at many shops helps even skilled mechanic's have a advantage to diagnose the problem more easily especially with deciphering more about what multiple codes may be really telling you.

The AC Delco 25186687 ignitition coil for that vehicle is around $100

 

[Andy Greene]

Yeah when I changed the vc gasket , and removed the boots from the plug end of the packs, one of the ends was broken- The ceramic portion, I had hoped they where only arcing in the oil, hence the vc gasket and plugs while I was there at 70k. I HATE tossing parts at something, but I cant overlook the obvious either-

Will try a new coil pack Monday. We just dont have the funds for this right now.............

 

[Daniel's Racing]

It could be misfire caused by fuel injector/injection system issue also. Airflow sensor another common culprit.

 

[johnsteltzer]

Any time

Hey i have been a mechanic for 38 years take the wire off the plug and stick a phillips head screw driver in the end of the wire then crank the car up then take the screw driver bye the handle and get it close to something metal on the motor and see if it will jump fire if it does the coil pack is good

 

[JimZaremski]

not that it helps you diagnose the source of the problem, but per OBD-II standards a flashing MIL/CEL means "repeating misfire, catalyst damage imminent." A failed ignition coil is a common cause.

 

[Hydro Junkie]

One other thing to look at. How good are the spark plug wires? I've seen similar issues caused by one with a damaged outer insulation. If the spark plugs are all visible on the front or side of the engine, start the car while in the dark. A bad wires insulation will normally allow arcing between the wire and close by metallic parks. In a darkened environment, an arc is clearly visible.

 

[Andy Greene]

Yeah , no plug wires here- one coil pack with 4 plug inserts so to speak on a hemispherical type head. I wrote service for 15 years and turned a wrench the better part of my life-

So , I have decent handle on the basic diag stuff- That said - I know the coil pack has a broken tip and until I eliminate the obvious failures, I/E oil filled plug wells/ 70k plugs -

Broken coil pack tip - all the diag codes in the world wont help me if my failure codes relate to the failed parts I cant turn a blind eye too

Was just looking to see if there is any here that turns a wrench on these vehicle on a reg basis , that may save me a step or two .

 

[dave roach]

If the coil pack is broken and the spark is jumping.

 

[Dan Kramer]

I know it costs, but why not take it to a gm dealer and get it diagnosed correctly. some of these issues are covered by warranty if under 100000, some have bulletins , if my tech I-d was current, I would look it up from home for you. it expired yesterday. and they will have to give me a new one Tuesday. my body shop manager was having trouble with her little Pontiac, she kept trying to guess it out with advise from different people, I went up front and put in the numbers and it was a $117.00 $ fix, a gm problem with the pvc valve in the valve cover, ,when we pulled up the bulletin it showed the correction and part #. .

 

[SayMikey]

Codes are a must,Those cars also have injector issues. Plugs are a couple bucks each throw them in. You can unplug one injector at a time to determine which cylinder is missing.

 

[Rick Sowell]

Andy, you need to see what codes it is flashing, if those codes relate to the cylinder that has the broken plug boot then you probably found the reason, if it is for a different cylinder then it probably is the coil pack as you suspect. find some one with a code reader and go from there. as a 30 yr. Ford tech I think you are on the right track. keep us posted.

 

[Andy Greene]

New coil pack fixed it- actually runs better than it has in some time- no more tip in hesitation or occasional miss at idle with the air on.

Glad I have not lost my ability to follow my feeble brain thought on diag - lol .

 

[Mike Byer]

Good deal Andy, actually todays cars are easier to fix than ever if you can communicate with them, they will tell you what they want. Been fixing Mercedes and other Euro cars for 40+ years, it's a lot different now than it was back in the 70"s, no guessing any more, just do what the scanner tells you to do and all is good. But brakes still grind and water pumps still leak, scanner won't help there.

mb

 

[Andy Greene]

I hear ya Mike, unfortunately being 10+ years removed from my dealership days, I didnt have access to a scanner other than the parts store free code pull.

On my test drive I swung back by for them to clear the code for me and they wouldnt- I get why - but really

, just plug it in , I will accidentally push clear codes

 

[Mike Byer]

Not sure on that on that car but it might respond to a hard reset, unhook the battery for a few minutes