I've been putting the final pieces together on my swap and have been trying to get it started for the last month. Motor cranks just fine. i get one combustion cycle from initial starting crank - here's a vid

Here's the basic setup and scenario/troubleshooting i've done

LQ4 - callies H beam rods and Wiseco 4.030 pistons
stock 317 heads
Brutespeed blower cam - 232/240
76mm turbo
2004 GTO PCM and harness (emissions stuff removed)
-VATS removed
Bosch 044 fuel pump - 60psi at the On and Start positions (via aeromotive FPR)
60lb Siemens injectors - have been flow tested and are not stuck
motor runs when spraying starting fluid constantly through the intake
Noid light test done - very, very faint light comes on with the first initial crank but nothing after that. this was the same across all 8 cylinders.
Gave injectors 12v power and grounded all 8 injector pins in the Blue harness connector along with Noid light tester and each injector plug lit up.
I thought the injector drivers in the PCM were bad, so i bought a 2nd PCM and had flashed to the same tune as the original PCM, same result.
I've checked the PCM constant 12v pin and the 2 ignition pins in the PCM connector and get battery voltage
I've checked all 8 ground pins in the PCM connectors and get less than 2 ohms resistance (.8 IIRC) at each one
I had a friend with HP Tuners come over and scan the PCM while cranking to see what's going on. Getting no injector pulse width at all. everything else is registering.

Since it runs off straight starting fluid, i can pretty much rule out everything but the injectors.

Can anyone think of anything that could be causing this? do the Cam or crank sensors have a direct impact on the injectors? I have the service manual and will be going through and testing these 2 sensors and replacing if needed.

Thanks for the help!

 

Good place to start, would be to post your tune file. Has anyone done anything with the VE tables of MAF curve?

 

I'll see what i can do about getting the tune file. i did have my tuner do a bench tune for VE to give me a "working" tune to get it drive to account for cam and injector changes. I'm not running a MAF, so that was a good point that i brought up to my tuner. waiting for his response.

 

I'm going to go out on a limb here, and say that the MAF was not completely disabled in the tune. Seen it before.

 

i ordered HP Tuners last night. should have it by the end of the week and will try and pull the tune file over the weekend.

 

Nice! Order an NGK AFX wideband while you're at it, so you can start dialing in your tune.

 

i have an AEM UEGO for my wb and will try to get that to work with HPT

 

HP Tuners came in today. i'll work on pulling my tune down and comparing other tunes over the weekend. Probably going to spend all night playing around with this and getting familiar with everything

 

Im new to this whole thing lol. But i have a 02 2500 hd 6.0 lq4.that has been sitting for 2 months now because i have no injector pulse. I have changed the pcm, crank sensor, checked codes with a scanner and havent figured it out yet. Truck cranks fine and will run if i feed it starting fluid and keep feeding it.i have no security light on while keys are in. Everything works as it should except injector pulse. So basically im wondering if anyone knows of a way to use a jumper wire to send a signal to the pcm to turn on the injectors? Im desperate to get it running and i have a caburated 350 that im about to swap in if i cant get it going. Im all out of ideas and any advice will be greatly appreciated.

 

Suggest you not hijack this thread.. Instead, start your own.

 

Vats ?

 

that was my first thought, but it's set to NONE

 

Got HPT setup and running tonight.

Here is the tune i pulled from my PCM. I'm still getting familiar with it all, so please let me know if you have any questions or if something jumps out at you.

 

Wrong reluctor on the crank? 24x or 58x harness ? Year of LQ4?

 

This is unlikely, but a bad ignition switch or signal will cause this issue too. Know from experience. Was a blown fuseable link or something. Found dead zone in wire and jumped wire from ign to pcm ign pin. Started right up.

 

2001 Lq4 and 2004 PCM/harness, both are (should be) 24x

 

checked this, ignition source is fine.

 

Any solution yet? I've been away, and have not had time to look at your tune file, but am wondering.....did you check to make sure that all PCM power and grounds are wired/functioning correctly?

 

I had this problem, I had ignition wired to my harness but it was not an ignition powered while cranking. I had a hunch one day and just jumped battery power to my ignition circuit and boom fired right up! Hope this helps. Just have someone hold a test light while you crank. Mine would pop or fire as I turned the key away from cranking.

 

IAT built into the MAF that is removed or is it already separate? This is easily checked by turning the key to on and running the scanner and seeing what the IAT is reporting. If it's some ungodly negative number then it's built into the MAF and you need a breakout harness.


You need to turn off P0101, P0102 and P0103 by unchecking it and setting it to 3.
Why is P0106 unchecked?