2002 L59 Tahoe, What's wrong here?

[Collin Smith]

Can someone please explain the 'Fuel Trims' to me? Also I have a bad ticking noise at cylinder 8, but when I unplug my ignition coil or the fuel injector the ticking noise stops. I have a rear exhaust manifold bolt that is broken on the same side as well, I don't know how this helps but....Anyone????

[Alvin]

The fuel trims have nothing to do with a tick. They can be addressed with tuning.. Likely cleaning the MAF if its a stock truck will make a big difference.

You probably know this already and might be related to your testing but you have a

P0358 - Ignition Coil H Primary/Secondary Circuit (Current)

code

[SiriusC1024]

Wonder why that code is so common? Is there a design flaw?

[Collin Smith]

when i unplug the 8th coil the ticking stops also the fuel injector unplug it and the ticking stops

[5FDP]

Well, no explosion in that cylinder can make the sound stop. It's just an air pump at that point, no bang from the fuel being ignited. So the ticking noise from an exhaust leak will likely stop.

[Collin Smith]

Thankyou that makes since. any pointers on getting the broken bolt out?

[SiriusC1024]

Wax. It will creep like penetrating oil at high temps without flashing off like PB does.

[TheMechanic]

I have pretty good luck with a regular right angle drill and EZ out. Can be done with the manifold still on but much easier with it off. GM has a new style bolt that is supposed to be less likely to break. I replace them any time they are removed like a head bolt.

[Alvin]

We use easy out or more often just weld to the bolt and it comes right out after that.

This tool looks promising.

https://www.motionraceworks.com/prod...-drill-fixture

[TheMechanic]

We use easy out or more often just weld to the bolt and it comes right out after that.

This tool looks promising.

https://www.motionraceworks.com/prod...-drill-fixture

That looks nice. I'm going to see if my machinist cam make me one of those. Like the drill guide for perfect 90 degree X 90 degree drilling.