back fire at wot

[mjp87]

My car is backfiring out the exhaust at full throttle. It idles a little rough but not that bad. It runs fine other than wot, If i ease into the throttle slow and steady boost kicks in and it takes off fine. I have just installed 009 injectors with turbo tweek street chip for 93 octane.
my mods are
big mouth cold air/ 3 1/2 inch mass air pipe
ls1 maf/ translator
stock intercooler with dutt-neck
adjustable fpr/ 340 fp/ hot wire kit
160 thermostat/ arizona gn radiator
hooker cat back with test pipe
scanmaster
turbo is stock

I am still learning with these cars, here is my scanmaster read out engine warm and in park.

02's all over, no higher than 781
af-04
l8-30
bat-14.2
int-128
blm-129
mph-00
clt-162
ats-41
rpm-825
tps-.42
iac-30
cc-245
nal-00

coil pack/ignition module are new.
One question about boost?
The new tt chip calls for 16-17 lbs of boost.I do not have a boost gauge but I have a adjustable wastegate actuator that I set it to the same length as my stock one. Does running less boost then what the chip calls for a problem.

any help would be appreciated,
thanks,mike

 

[that guy]

My car is backfiring out the exhaust at full throttle. It idles a little rough but not that bad. It runs fine other than wot, If i ease into the throttle slow and steady boost kicks in and it takes off fine. I have just installed 009 injectors with turbo tweek street chip for 93 octane.
my mods are
big mouth cold air/ 3 1/2 inch mass air pipe
ls1 maf/ translator
stock intercooler with dutt-neck
adjustable fpr/ 340 fp/ hot wire kit
160 thermostat/ arizona gn radiator
hooker cat back with test pipe
scanmaster
turbo is stock

I am still learning with these cars, here is my scanmaster read out engine warm and in park.

02's all over, no higher than 781
af-04
l8-30
bat-14.2
int-128
blm-129
mph-00
clt-162
ats-41
rpm-825
tps-.42
iac-30
cc-245
nal-00

coil pack/ignition module are new.
One question about boost?
The new tt chip calls for 16-17 lbs of boost.I do not have a boost gauge but I have a adjustable wastegate actuator that I set it to the same length as my stock one. Does running less boost then what the chip calls for a problem.
any help would be appreciated,

thanks,mike

Your numbers look good. Your IAC is a little off/high, 10-20 is best with a TT chip.

Can you post some WOT readings from your scanmaster? Running less boost shouldn't be a problem. I assume it is a stock actuator since it is a stock turbo.

 

[BOSS 6]

check your coil pack

 

[ngnowner]

check your coil pack

+1 OHM out the towers, had the same problem, one of the towers was at full resistance.

 

[TurboDave]

Does running less boost then what the chip calls for a problem.

any help would be appreciated,
thanks,mike

No, BUT.... Running without a boost gauge is trouble waiting to happen.

 

[BlackoutDrunk]

Have you replaced/checked your plugs. I was having a problem with it breaking up at WOT and a slightly rough idle. Changed the plugs idle was smoother and no more break up. Easy enough to check/fix.

 

[mjp87]

back fire

I will check coil packs/plugs and I will get a boost gauge asap.
thanks for the suggestions.
mike

 

[86BLACKT]

My EGR went bad and after it warmed up, I had total junk, also MAF made mine back fire a couple years ago. Just food for thought

 

[GNRick]

Could also be the TPS sensor. Mine was fine with key off, but under load my scan tool showed voltage decreasing at one point when it should have been going up. A new TPS sensor cured the WOT break up.