Slight miss but 6 mpg!!? Need help

[Chetty mo]

Read if you dare.

It doesn’t get good until the bottom of page 9. I hope this isn’t your issue but it was for me. Wiped out lifter and camshaft. I tried to diagnose everything before I tore into the engine. I also had a slight miss only at idle and accelerating from idle

SOLVED: Another misfire chasing threads (2008 express van)

Details 2008 Chevy express 3500 cargo van 6.0 58k miles. 8k running hours. No service history So after last weeks fun with the wife’s MB. (I think it’s resolved). my work van started having a rough idle. Code reader says P0307 misfire cylinder 7 confirmed. So I went and changed out the...

www.tahoeyukonforum.com

 

[Chetty mo]

What caused you to install the new throttle body and throttle position sensor? Anything particular or were you just pulling the trigger on the parts cannon? Not throwing stones, but it’s always good to know what, if anything, drive previous decisions.

No I totally understand. but at this point it’s so frustrating. There’s no shop here in Orlando I trust to take it to. I’d love to drop it off and have a proper diagnosis but I just don’t have a place. I think I watched every scanner scanner video he has to try and learn but it’s a lot to take in. I did learn about the evap system. And all that’s replaced now.

 

[Chetty mo]

I’m doing the oil servicing this weekend. And plugs and wires and coils as well. Here’s some more O2 data.

 

[swathdiver]

Ok @Chetty mo , have you run the smoke machine on the system yet? I suspect intake gaskets. Try tightening them down first.

Your throttle percent is high and if you took the throttle body off and cleaned both sides and the edge of the plate and it is still too high after a drive then you might consider replacing it.

Definitely get new plugs and wires for it. 748UU is for OE wires and 19417055/41-162 are the current OE plugs. No anti-seize on the plugs and use dielectric grease on the plug side of the wires.

 

[Chetty mo]

I put all new plugs and wires and coils. No change. I put new throttle body. No change. All new charcoal canister. No change. New purge valve and vent Solenoid and filter. No change. I sprayed starting fluid all around intake while running. No change. I’ll try the smoke test but I’m close to just selling it. I’ve tried for about a month now and it’s getting ridiculous and expensive.

 

[Chetty mo]

Also new plugs and air filter and engine flush then fresh oil and filter. No change.

 

[ivin74]

I put all new plugs and wires and coils. No change. I put new throttle body. No change. All new charcoal canister. No change. New purge valve and vent Solenoid and filter. No change. I sprayed starting fluid all around intake while running. No change. I’ll try the smoke test but I’m close to just selling it. I’ve tried for about a month now and it’s getting ridiculous and expensive.

Are you using oem parts or aftermarket?

 

[Chetty mo]

Depends. But turns out my ecm (computer) is bad. Ordered one. I’ll let ya know what happens.