68 c10 ls2

I have an 02 LQ4 6.0L with a maggie 112 on it. I had a tune in the truck and it was running fine (this tune would kick on the check enegin light for maf voltage low). I had the truck running doing a quick log with my HP Tuners. I shut the truck off and downloaded a new tune in the truck fired it up and now runs like crap. My kpa's are reading 180-190, my mech boost gauge is reading 0. So i put the old tune back in it(the one that it ran good on) and now that tune also runs like crap. I reaplaced the MAP sensor twice now and still dosent run good. If i unplug the MAP while the truck is running it will smooth out and run good. Can anyone help me?

68 c10 ls2

tonight i hooked up my MATCO scan tool to the truck, with the key on (not running) the MAP was reading 30kpa. The air pressure here right now.

5.7 ute

What does it read in the HPTuners scan tool key on engine off? If you are running anything other than a 1 bar map sensor the generic tools will not read correctly.(The voltage to kpa conversion will be out)

68 c10 ls2

I havent tried that yet, so i will do that tonight. I have a 2 bar map sensor in the setup.

68 c10 ls2

I just hooked up HP Tuners and ran a log with key on engine off and the map reads 0. I then started and ran the truck for about 30sec, then went and checked to see how how the headers were and 5,6,7,8 were hot and 1,2,3,4 were cold/warm. I then pulled a spark plug on #1,#2 and they were wet with fuel. so i dont know what the f*** is going on.

68 c10 ls2

can anyone make sence of what is going on? Sorry but i live in MN and winter is coming soon and i want to get this fixed before that happens. Any help would be greatful!!!

5.7 ute

Sounds like a wiring issue or dead pcm to me.

68 c10 ls2

i aready replaced the pcm once.

Matt@SNLPerformance

iTrader: (1)

Can you post your tune file and a log of what is happening?

68 c10 ls2

9-20-10.hpl

log 3.hplThe 1st log was from yesterday 9-20-10 and the 2nd log was from right before i started having all my problems.

68 c10 ls2

I just unpluged the TPS and the truck runs "better" (still has a studder/missfire) and all 8 header pipes feel the same temp.

Matt@SNLPerformance

iTrader: (1)

Have you checked your Engine fuses? Also when you talk about cylinders 1,2,3,4, do you mean they are on the same bank like passenger and driver?

68 c10 ls2

Im running the painless 99-02 6.0L wiring harness and i checked all the fuses and relays and non of them were bad and checked all the factory fuse box too. By 1,2,3,4 its the accual cylinder number. So 1,3 on the drivers side and 2,4 on the passanger side.