Turbo 5.3 possible tune issues
The vehicle.
2001 Silverado p01 ecu
3 bar ls1 style map from efisource
Gen iv intake with 92mm the
on3 7875 turbo with fmic
The issue.
I tuned this using hptuners and so far I am running 10psi according to my boost gauge. AFR looks like it's supposed to. It ran good for the first 9-10 pulls I made at the dig spot, drove it home smoothly no issues. The next weekend when I did the pull it felt a little weak in higher boost range. And when I let out it misfires hard until I free rev in neutral then it's fine unless I try and boost again.
What I've tried
New wires/plugs
Vcm logs look okay.
coils are all firing at idle
What I'm questioning.
At 10psi it reads 135kpa
At idle it reads 70kpa
Does that seem correct? Or do I have a bad out of the box map sensor. Linear and offset where provided by efisource.
Any suggestions? Tia
The vehicle.
2001 Silverado p01 ecu
3 bar ls1 style map from efisource
Gen iv intake with 92mm the
on3 7875 turbo with fmic
The issue.
I tuned this using hptuners and so far I am running 10psi according to my boost gauge. AFR looks like it's supposed to. It ran good for the first 9-10 pulls I made at the dig spot, drove it home smoothly no issues. The next weekend when I did the pull it felt a little weak in higher boost range. And when I let out it misfires hard until I free rev in neutral then it's fine unless I try and boost again.
What I've tried
New wires/plugs
Vcm logs look okay.
coils are all firing at idle
What I'm questioning.
At 10psi it reads 135kpa
At idle it reads 70kpa
Does that seem correct? Or do I have a bad out of the box map sensor. Linear and offset where provided by efisource.
Any suggestions? Tia
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If you meant -70kPa you have a vacuum leak.
If you truly meant 70kPa, your MAP sensor is probably fucked, or the calibration for it is fucked. If youre MAP says youre boosting 130 and your boost gauge says 10psi, youre probably dumping too much fuel, which explains the power loss and backfiring.
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