Tunedperformance told me to ask you about a problem I am having, here is his response to me about my car never going in to closed loop.

Im confused why its not going into closed loop the o2 is swinging and you have o2 cross counts, the ect is high enough. Im wondering if knock counts can cause it not to go into closed loop. You might get rbob to answer if you post in the diy prom section I know a fair amount about the gm tpi ecms but you have been stumping me

My knock counts are 209, I am assuming it is from the roller rockers I just installed, they may not be set just right yet. Any assistance you can offer is appreciated.

 

Is the O2 swinging far enough? There are upper & lower thresholds that the O2 signal needs to exceed before the ECM will go closed loop. Such as 200 mV and 800 mV.

RBob.

 

O2 is 61 mv cold and 158 mv warm.

 

Have a data log? And, what makes you think that it isn't going into closed loop?

RBob.

 

This is what he obtained from his auto xray. Bye the prom id it looks based Off the ARAP. He can get the iac counts down at warm idle 15-30, but im wondering about cold start enrichment seems way to rich and the target idle maybe low. His fans come on sometime when the key is on so it could be a dip or piggyback issue. The tps has been modified to be lowered down to .54v.

Cold Warm
Prom ID 4131
Rich/lean.....lean lean
Integrator....128 134
Learn control..disabled disabled
Block learn....25 21
IAC.........160 160 (???)
open loop open loop (???)
O2.....61 mvolts 158 mvolts
rpm...1125 (peddling it) 750 (on it's own)
cross counts..128 146
temp...66* 161*
MAF... 0 (?) 130 gr/sec.
Prop O2 step..lean lean
tps 1.01 (also peddling) .90 (experimenting)
Cruise engaged (???) cruise not engaged ?
Knock sensor...209 209 ( roller rockers?)

 

The INT at 134 means that it is in closed loop.

The knock counts could be from cranking the engine to start it.

RBob.

 

Thanks for the suggestions Rbob, I believe I have it taken care of. It's running great again.

 

So what was the issue?

 

auto x-ray uses vin numbers for the mask I think it was odd data from $1F. The throttle blade stop screw was opened up more and I think this solved his running issue.

 

Yep, that was it. I may still have an open loop problem with the tune, (fuel) but other than that it is running great. If hat is the case, I'm sure pcmforless will take care of it for me.

 

sounds like you need to tell alvin to cut back the fuel for cold start enrichment vs coolant temperature.