V6 to V8 2 Bar OS no start
I will try and keep things short and sweet. I've been lurking some time and recently finished a swap vehicle that I am having trouble starting. I am pretty sure that my problem is tune related but I've not been able to rule out differences in PCMs when swapping from v6 to v8.
What I did was swap 99 sierra 5.3 lm7, ss2 cam, rev 9 turbo, decapped injectors, walbro 450, 2 bar MAP into a 2002 rcsb 4.3. All was well until i attempted to start the vehicle and didn't have spark. I went and purchased a spark tester as well as a fuel pressure tester. I checked all sensors (new BTW) and wiring including pulling my starter and checking my crank & cam sensors. I fixed what I thought were shoddy pigtails and grounds but STILL NO SPARK.
I originally used the 411 PCM from the 4.3 v6. I did a write entire and switched it to 2 bar custom os. NO MAF, with IAT wired correctly and PIDs working. I was able to see RPM as i crank the engine over via the VCM scanner. I got fed up with trying to find my spark problem and slapped my original 896 PCM from the swap truck in and BAM fires right up and dies.
My actual question is, is there a known problem when switching between 896 (1999 year) and 411 (2002 year) or is it possible that I messed up in the tune? The tune I used came from the sloppy tune cabinet and i cherry picked information from the tune using the compare feature so that I only used two credits in tuning my swap. HARDWARE PROBLEM OR OPERATOR ERROR? Thanks guys
Reply With Quote
