hey, guys I'm having a little bit of a problem here. I just got home from a NYC 5 Borough cruise and I'm running crazy lean and knocking all over the place. I was fine in the morning before we left around 11AM and wasn't getting any knock until around 2pm. The weather in the morning was high 60's and by afternoon it was around high 70's.

I looked at my logs in the morning and was spot on. For some odd reason while cruising and little speeding here and there, I hear my laptop beep like crazy. I figured the Temp Compensation wasn't enough so I increased it by a point, still no difference, I even removed everything and set it to 0 across the board and still no difference.

I figured let me just add some fuel from 2250 rpm 10-30 load to 4000rpm 10-30 load and added 10 across the board and that help me improve my A/F.

Why did this happen all of a sudden? The Temp Compensation doesn't even help this time.

 

Update:

I tried to reset the ECU (Disconnected Battery) and let the car sit and cool down for 5hrs. I plugged everything back and did some logs and the freaking thing is now back to normal I brought back everything to what it's used to be and now my A/F is spot on again. Hmmm 4-5 hours of driving and Utec went to La-La Land

 

Bad ground with heat-soak on the engine? Do you run a 'earth grounding' kit? Check the connections between the UTEC and the ECU? Abraided/worn wire causing a short on the power or ground or MAP sensor wires to the UTEC (there was an issue recently with the common ground for the UTEC not being 'sound' and causing difficulties with the output from the UTEC)? The list is near-endless but that should give you a start.

 

Well first off, is your UTEC tuned in piggyback mode or standalone-at-load?

 

I got a feeling those injectors are doing some funny things on your car.Every other UTEC we ever tuned was dead on 95% of the time.

 

what kind of injectors are they?

 

The ones that come with the STS kit. aka Deatschwerks...

 

i personally have had no issues at all with deatschwerks, they are my savior when i do have injector issues on a car.

maybe its something with the MAF sensor and the IAT inside reading incorrectly and then the utec temp correction over correcting it in some way.



best way would be to post up the logs so we can take a look at it . i try to tell people not to adjust things on the utec. us tuners spend countless hours to try to get it all perfect and if any issues ever, please bring the car back so we can look at it

 

I had a feeling that the injector was going bad coz what ever I do in Utec it seem doesn't matter. At that time I just wished I had a Fuel Pressure Gauge coz I was afraid that maybe I'm not getting enough Fuel. I made sure that Utec was compensating through looking at the Dashboard and it don't matter what MAP I used. I dropped my car again to have my bumper repainted this morning and so far my A/F is still spot on.

Edit:
I was mainly just adjusting my Temp Compensation but when I got desperate, I just changed a few block (mainly lower rpm and low column) to see if Utec is actually using my map. Now that I'm OK, I brought back all the settings

 

I'm at Standalone-at-Load. I was able to go home and stayed away from boost at that time. At that time when I hit boost at around 1-4psi my A/F was from high 13's to mid 12's.