Weird Issue, going lean at WOT(Ls1 Rx7)
Then why isn't your tuner properly diagnosing your high and low voltage codes for your TPS? Doesn't seem like you got a proper diagnosis at all. O2s have nothing to do with that. Replies are based on what you post, not reading your mind.
if you have not done so already put a gauge on the fuel rail and tape it to the windshield so a passenger can watch for fuel drop under load
this has ended up being the problem in several I've seen...and they all had "brand new" pumps, injectors, lines, etc
this has ended up being the problem in several I've seen...and they all had "brand new" pumps, injectors, lines, etc
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the story i was avoiding telling is that my tuner said my car is stuck in closed loop and wont go into open loop at WOT and when it hits 4500 rpm the afr spikes (exactly like the original post's problem). he smoke tested the intake manifold and found no leaks. i have pending low and high voltage codes for my tps and my friend had a similar problem and it was his o2 sensors. i did get the proper diagnosis and do have the proper tools to find the problem, im just trying to see what his fix was so it saves me time. thank you for your awesome tone though it really helps.
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Weird Issue, going lean at WOT(Ls1 Rx7) Sounds like you have a whole lot of physical problems and tune problems.
Can you post some log files.
If PE fueling is set to stoich, then the PCM may be able maintain closed loop (since commanded fueling is not deviating from stoich)... you should not run PE set at stoich.
How do you know that it's stuck in CL...?
There is also the possibilty that your tune is set to do OL STFT trimming (on stoich cells in the OLFA table) which also means PE is set to stoich (the PCM selects the richer of the enabled tables, i.e. OLFA or PE in OL).
So as you can see, the tune has some problems...
And as said above, you have to get the TPS and other physical problems diagnosed (before doing anything in the tune)...
(the GM Service Manual has diagnstic charts to help you pinpoint the cause of each physical problem).
Can you post some log files.
If PE fueling is set to stoich, then the PCM may be able maintain closed loop (since commanded fueling is not deviating from stoich)... you should not run PE set at stoich.
How do you know that it's stuck in CL...?
There is also the possibilty that your tune is set to do OL STFT trimming (on stoich cells in the OLFA table) which also means PE is set to stoich (the PCM selects the richer of the enabled tables, i.e. OLFA or PE in OL).
So as you can see, the tune has some problems...
And as said above, you have to get the TPS and other physical problems diagnosed (before doing anything in the tune)...
(the GM Service Manual has diagnstic charts to help you pinpoint the cause of each physical problem).
Last edited by joecar; Dec 5, 2015 at 02:48 PM.
Sensor overheat can be a problem if it's too close-in
(especially bad, is before the turbine housing). That
puts the wideband controller out to lunch.
Misfiring, even one unbalanced injector at WOT can
really spoof sensor readings even if the controller is
working right.
(especially bad, is before the turbine housing). That
puts the wideband controller out to lunch.
Misfiring, even one unbalanced injector at WOT can
really spoof sensor readings even if the controller is
working right.
