Engine Pops/backfires under acceleration

Welcome!

By registering with us, you'll be able to discuss, share and private message with other members of our community.

SignUp Now!

hemi8

Goin Sideways
TurboBuick.Com Supporter!
Joined
Jun 6, 2001
Messages
1,024
Over about 14-15 psi the engine will pop/backfire, nothing drastic but enough for me to pull out of it. Changed recently from a 3" MAF to 85mm ZO6 but that was a few months ago. Changed the settings in the MAF translator per Eric's instructions, it has the latest chip installed. A couple months ago it was starting weird and I tracked it to a loose crank sensor, reset it and tightened it up, maybe by being a little loose it screwed it up? Anyway, to try and solve it I have changed:
Plugs
Plug wires
Coil
Ignition module
No Change. Tuesday I am going to change the crank sensor and go for a spin. I have the wideband tracking TT chip and Razors alky, both are working fine and I have not touched them. Twin pumps by Racetronics last summer. Only other things that come to mind that could possible cause it are maybe a failing:
TPS
cam sensor
??????????
I have PL and scanmaster, what should I focus in on?? No Knock is being detected and the A/F is right where it always is under hard throttle 10.8. If a sensor is malfunctioning it is not setting any fault codes.
Mike
 
Sounds lean to me do you have enough FP ?? Do you have a good boost gauge

Posted from the TurboBuick.Com mobile app
 
I have 2 boost gauges, one in my face and one on the wastegate controller, read the same. I have a FP mechanical gauge hanging in my garage I can hook it up and try that to see if its falling. I normally run 21-22 psi.
Mike
 
Check FP and then check the crank sensor again and cam sensor sometimes gets worn and needs some tweaking

Posted from the TurboBuick.Com mobile app
 
Hooked-up the pressure gauge last night, just need a window of time to go for a test run.
Mike
 
DSC03701.JPG
So I noticed a drip of coolant underneath and since I can't see anything on the front of the engine I started removing parts, and then I noticed this............... Think the turbine bent blades ramming into the housing and digging up the
DSC03701.JPG
metal could have be the cause? What the hell??
Mike
 
Turbo cartridge is no good excessive play in 360 thrust bushing and or worn out bearing depending if its a bb turbo or 360 thrust bushing dont drive anymore until its rebuilt pm (BISON) I think he rebuilds them or contact precision turbo.

Posted from the TurboBuick.Com mobile app
 
Yeah looking closer you may need a new turbo looks like impeller contacted compressor housing..

Posted from the TurboBuick.Com mobile app
 
Well, it worked great for 15 years, guess I shouldn't bitch too loud. Is the John Craig TE45 a good replacement for the TE63?
Mike
 
Honestly not sure bison would know

Posted from the TurboBuick.Com mobile app
 
Back
Top