understanding diagnostics
recently had a small diagnostics done, but need to know if the results are a major cause for concern...as well as what could be causing the problems.
things the tech pointed out were:
spark advance: 6.0 degrees
long term fuel trim - bank 1 +4.69%
short term fuel trim - bank 1 +23.44%
long term fuel trim - bank 2 -7.03%
short term fuel trim - bank 2 +24.22%
in english???
car has 85,000 miles. MREV w/ spacer, JWT popcharger, Borla exhaust for engine mods.
things the tech pointed out were:
spark advance: 6.0 degrees
long term fuel trim - bank 1 +4.69%
short term fuel trim - bank 1 +23.44%
long term fuel trim - bank 2 -7.03%
short term fuel trim - bank 2 +24.22%
in english???
car has 85,000 miles. MREV w/ spacer, JWT popcharger, Borla exhaust for engine mods.
your car is dumping fuel for some reason. eventually the long term will go up also. Original O2 sensors? But both at the same time? Not usually. Check for a leak around ur spacer. Spray carb cleaner or water.
when you say dumping fuel? so it's running rich and using too much per spark?
I've done the carb cleaner and cigarette smoke check but never seen any leak.
I know I have 2-3 stripped bolts on the bottom of my plenum, but it seems to still have a good seal.
And yes, stock o2 sensors.
I've done the carb cleaner and cigarette smoke check but never seen any leak.
I know I have 2-3 stripped bolts on the bottom of my plenum, but it seems to still have a good seal.
And yes, stock o2 sensors.
Last edited by nismospec; Nov 4, 2010 at 09:04 AM.
No it is running rich, very. Too much fuel, not enough air. When you see STFT +24% or so the car is adding 24 percent of fuel for some reason. You have to find that reason. Either 24% more air is entering, or the car thinks 24% more air is entering.
so troubleshooting begins at.....?
- cleaning pop charger
- cleaning MAF sensor
- checking for exhaust leaks
- checking for leaks in plenum
does that sum it up? is there anyway to clear the ECU so that it can re-learn the flows, or does that have to involve an ECU flash?
guess what i'm trying to discover is if it can be easily fixed, or if a full tune is needed. (by full tune i'm saying something like Uprev & Osiris like you have).
- cleaning pop charger
- cleaning MAF sensor
- checking for exhaust leaks
- checking for leaks in plenum
does that sum it up? is there anyway to clear the ECU so that it can re-learn the flows, or does that have to involve an ECU flash?
guess what i'm trying to discover is if it can be easily fixed, or if a full tune is needed. (by full tune i'm saying something like Uprev & Osiris like you have).
No, this is a running condition most likely. Unless it started right after you did these mods? A tune is a good idea for what you have, mod wise. You have the right idea where to start. Some cars are different, I dont know if disconnecting the battery is enough to clear the learned fuel trims in this car. I know there is a ecu reset procedure on this forum somewhere.
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