crazy knock problem

[hucks1987]

ok guys I need some help.

I have been having this crazy knock issue. its there some times and some time its gone. I seem like every time we get the fuel trims right, the next time I drive the car, the fuel trims are out of whack.

last night, I finished installing my meth, using 100% so I took it for a ride, the first log, there is zero knock, all the pulls I did and nothing. I stopped to turn the start point up alittle, turn the car back on and right away I had knock, at idle, and then again, all the pulls I did had knock.. Is this possible that maybe the fuel filiter needs to be replaced? is this fake knock, I cant tell.

thanks in advance

[hucks1987]

I guess you can throw out the fuel filiter, the cobalts don't have one

[codename Bil Doe]

They do have one. On the Cali models it's integral to the pump/sending unit thingy and sits on top of the tank. Not to be confused with the fuel sock. IIRC it was ~$85 for the pump/filter unit and not worth the hassle of dropping the tank to replace. Supposed to be a non-serviceable item in Cali models I guess.

[ericemir]

I hate phantom kr in our engines... my car always looked like the second log.... and melted piston. 23 psi 15 degrees top end kr everywhere....

[cobaltssoverbooster]

hahah sorry Eric happens to all eventually

[hucks1987]

It just started doing it, car stat for about 6 months while I was deployed, came back, and it was fine, fuel trims were alittle off until I filled up again, then a month or 2 ago this started going on....

And I really don't want to melt wisco pistons. Won't be a good day

[T-Man]

MAF needs some serious work. Also, your car is having issues with closing the TB. And unless my PID is setup wrong, your car is pulling over 25-26psi?

I also noticed that your car isn't hitting the same spark advance as you're commanding. Something is definitely wrong somewhere.

[codename Bil Doe]

MAF is def way off. I'm seeing same as T-Man. You're hitting up to 26.5psi.