Hi there,
First of all, my car:
1997 940 Turbo B230FK
Only modifications:
-TD04 15g @ 8 psi
-3 inch turbo back exhaust
-KL Racing 60mm intercooler
Stock 016 MAF, 6 months old Mustang 5.0 Bosch lambda sensor (same sensors) and injectors. No chips in fuel or EZK.
Brand new fuel filter and gapped BPR7ES plugs.
Now, my issue.
My AEM wideband gauge is showing me problematic AFR's at certain points of the rev range. When cruising and light load it's always at 14.7 as it should, but under boost it will first be running too lean, as low as 13.7 when really low in the rev range (around 2000 rpm). It will then start to progressively richen up as the revs climb, spending most of it's time in the 12.5/11.5 sweet spot. But when approaching red line, it will once again progressively richen up untill hitting low 10's, sometimes even in the 9's at 6000 rpm.
Here is a video to illustrate the issue; you can see the tach and AFR gauge simultaneously. This is a 3rd gear pull, cruising at 2500 rpm then floored to redline.
https://youtu.be/b66JVedyiEY
I don't know how a stock LH2.4 car is supposed to run AFR wise, but I don't think this is normal as it's not safe for my car.
What do you guys think? Boost leak somewhere? Crappy MAF or lambda sensor? What could be causing this?
First of all, my car:
1997 940 Turbo B230FK
Only modifications:
-TD04 15g @ 8 psi
-3 inch turbo back exhaust
-KL Racing 60mm intercooler
Stock 016 MAF, 6 months old Mustang 5.0 Bosch lambda sensor (same sensors) and injectors. No chips in fuel or EZK.
Brand new fuel filter and gapped BPR7ES plugs.
Now, my issue.
My AEM wideband gauge is showing me problematic AFR's at certain points of the rev range. When cruising and light load it's always at 14.7 as it should, but under boost it will first be running too lean, as low as 13.7 when really low in the rev range (around 2000 rpm). It will then start to progressively richen up as the revs climb, spending most of it's time in the 12.5/11.5 sweet spot. But when approaching red line, it will once again progressively richen up untill hitting low 10's, sometimes even in the 9's at 6000 rpm.
Here is a video to illustrate the issue; you can see the tach and AFR gauge simultaneously. This is a 3rd gear pull, cruising at 2500 rpm then floored to redline.
https://youtu.be/b66JVedyiEY
I don't know how a stock LH2.4 car is supposed to run AFR wise, but I don't think this is normal as it's not safe for my car.
What do you guys think? Boost leak somewhere? Crappy MAF or lambda sensor? What could be causing this?