hey guys, just installed KB's turbo kit and a nelson tuned PCM - cranked it up and it runs like complete **** and threw codes random cylinder misfire

any input?

 

Sounds to me like the tune got corrupt somewhere between making and programming. Ive seen this happen quite a few times. Im not real sure what causes it. Give them a call and see what they think about this. Im sure they would send you another tune to fix it.

 

turns out I just got mixed up, I had the bank 1 O2 sensor plugged into the female input for the O2 sensor that goes after the catalytic converter.. lol dumb mistake, but it fixed everything

I am running codes P0171 and P0174 Bank 1 and Bank 2 running lean.. idk wtf is up with that fuel pressure is good and everything

 

I'd highly suggest you take the truck to them and let them tune it in person if possible...it's just way more practical and safe IMHO

 

Those could be a vac leak.

 

Ah yes, the p0171 and p0174... Have had these codes from day 1 since i got tuned for the 60's...never had it with the 44's. Every one say vaccuum leak... not one.. smoke machined and all. I believe its something to do with tune and the large injectors

 

I had these codes on my 5.3 after a header install did the smoke and never found out what it was. Did a cam swap and they went away weird. If anyone has had this problem and found out what it was I would like to know for projects later down the road. If tune related what was done to correct the prob.

 

Hmm I would get it tuned in person but I am 7 hours from Nelson

I checked the vacuum, I did have a line I tied off that might have been causing the codes but after I plugged it up and cleared the codes the codes came back- but no check engine light this time, but the codes were still there when I plugged the scanner in

I can clear them and then pretty much immediately they come right back, even at idle - but again with no check engine light

 

Just my two cents here, but even when I did a simple cai install on my nnbs, my truck started throwing po171 codes. Took me a month or so to actually find the real problem. No one could figure it out, and I even ran a breather filter from my passenger side valve cover to see if that would keep the code turned off. Everyone kept saying vacuum leak , but then I got the idea to run the factory breather line right back into the new aluminum intake tube (to complete the circuit that I had broken) and I haven't seen that damn code since. Im not saying that is your actual issue, but I am saying to possibly look at your PCV system for the fix

 

Good point I will check out my Pcv lines, I didn't touch them during the turbo install but maybe something is wrong with it and is showing itself now