l92/6l80 will not start/can't read codes

[jorgensensc]

Originally Posted by 67Steven

Well, after a crap load of emails between Jon and I the last two days and little to no help from him other than he "needs to see the tune"...

I got sick and tired of trying to figure out what was wrong. So, tonight when I got home I unplugged the entire PSI harness and plugged in the OEM harness.

*A little background here: I bought the engine, trans and transfer which included the original uncut harness. Since it was from a Hummer, the wire harness to the ECM was extremely short, basically right in the space where my hydro-boost and brake lines were occupying. Wayne (tuner) modified my harness to be a stand-alone unit before I realized it was so short. So I made the fatefully wrong decision to grab the PSI harness since it put the ECM in the cabin.*

Anyhow, I plugged it in, connected the battery and turned the key on. Throttle pedal worked! I was a kid in a candy store! Turned the key to start and it started and idled! But died. It will start and idle for 4-6 seconds- I do not have the MAF, MAP or O2 sensors in place, as this was a quick install (and I stole those plugs for the PSI harness) just to see if it worked, so I assume when I get a good, complete harness it should work.

I am planning on an email to PSI tonight and explain what I did and see what he says. I have wasted 3 weekends and many week nights trying to track down problems on my end and it was his harness all along. I also spent a lot of time re-routing his harness to fit my install. I am trying to decide if I should have him send a new harness or just a refund and source a new one.

Oh, no throttle or transmission codes on the OEM harness!

I'll check back after my contact with PSI.

Great to hear!! Glad it is working for you. It probably isn't running right because it is probably trying to change over to speed density, rather than MAF. and your MAP isn't hooked up.
I'll be honest, at this point if I were you I would send the PSI harness back and just have your stock one modified to put the computer where you want it. You KNOW it works! But then again, I'm pretty frustrated with electrical gremlins right now!
Shawn

[67Steven]

Originally Posted by lynnfield

After doing some research, and finding both good and bad things posted about PSI I was leaning towards going with Speartech. Someone here on the board pointed me towards BP Automotive. I talked to Bill several times, he uses all the same production tooling as the factory to build his harnesses (same with Speartech, Howell and some others). The price was good, he returned all my calls, answered my questions, and I wasn't able to find any negative reports about his company.

Thanks for the info, I may be calling him tomorrow.

[67Steven]

Originally Posted by jorgensensc

Great to hear!! Glad it is working for you. It probably isn't running right because it is probably trying to change over to speed density, rather than MAF. and your MAP isn't hooked up.
I'll be honest, at this point if I were you I would send the PSI harness back and just have your stock one modified to put the computer where you want it. You KNOW it works! But then again, I'm pretty frustrated with electrical gremlins right now!
Shawn

I have heard it is not recommended to try and extend an existing harness, too many splices, that's why I went with PSI.

You don't have the option of returning it? I am leaning hard to that direction. Luckily I have had the same credit card company in excellent standing for 20+ years who will do a charge back no problem.

[Blackpony]

I highly suggest using bill with bp auto. I have dealt with him on a couple occasions when I built my harness, and even though I did not buy anything from him, he was extremely helpful with all my questions. I have seen a couple of his harnesses and cannot say enough about the quality and fitment. Check him out if you have not already!

[jorgensensc]

Originally Posted by 67Steven

I have heard it is not recommended to try and extend an existing harness, too many splices, that's why I went with PSI.

You don't have the option of returning it? I am leaning hard to that direction. Luckily I have had the same credit card company in excellent standing for 20+ years who will do a charge back no problem.

Yes he gave me the option. Unfortunately I had already run it and was on a deadline to get the suburban up and running since it was my daily driver. To top it all off I gave the harness that the engine came with away when I received the PSI harness. Then it took me so long to install it (because it was late getting here I missed my opportunity for the install window), and I spent do much time trying to hunt down problems and figure out wiring/ computer issues that it was well past the 90 day chargeback window. So I just made do with what I had.

[Houston Ben]

Sorry to butt in here but I am going through a swap (2011 5.3 w/6L80, harness all from same vehicle) and mine will only run 4-6 seconds also.
67Steven you stated

Anyhow, I plugged it in, connected the battery and turned the key on. Throttle pedal worked! I was a kid in a candy store! Turned the key to start and it started and idled! But died. It will start and idle for 4-6 seconds- I do not have the MAF, MAP or O2 sensors in place, as this was a quick install (and I stole those plugs for the PSI harness) just to see if it worked, so I assume when I get a good, complete harness it should work.

What do you mean by throttle pedel worked? What exactly did it do when the ignition was turned on but engine not started? Thanks for any help, I will let you know if I figure anything out on mine as well.

Ben

[jorgensensc]

Ben,
When you turn the ignition on and push the pedal, the throttle plate will move (open and close) just like a carb. That will tell you if your getting signal, or if there is another problem with the system that will prevent the computer from letting you open or close the throttle.

[Houston Ben]

Damn, look like I have a problem!! How can you tell if the pedal is the same one from the vehicle or at least form the same year?

[Hart_Rod]

Originally Posted by Houston Ben

Damn, look like I have a problem!! How can you tell if the pedal is the same one from the vehicle or at least form the same year?

It should have a part number or service number on it. Post a picture of your pedal.

[67Steven]

Originally Posted by Houston Ben

Damn, look like I have a problem!! How can you tell if the pedal is the same one from the vehicle or at least form the same year?

If you get a truck pedal it should work. Verify it is for your year and application, but I am betting most any 2011 -12 GM truck pedal will work. I have the correct pedal, just a bad harness.

Did you get any codes from it?

[67Steven]

Well, the PSI harness is out and ready for shipping. Jon gave me the option of having them run it through 'quality control' or get a refund. I told him with all the problems and incorrect layout of the harness, I wasn't too impressed with quality control, and I am opting for a refund.

I ordered a new relay block and fuse center to clean up my OEM harness, and should have it running next weekend! I will try to post a video of it when I get done.

[Hart_Rod]

Originally Posted by 67Steven

If you get a truck pedal it should work. Verify it is for your year and application, but I am betting most any 2011 -12 GM truck pedal will work. I have the correct pedal, just a bad harness.

Did you get any codes from it?

The 2004+ Vette pedal will work also. You just have to swap a couple of wires around on the connector.

[Houston Ben]

67Steven

Did you get any codes from it?

Nope, no code for it, it just wouldn't move. I will be getting my PCM back this week and will try again.

Hart Rod, I may change to that pedal later, it would fit a lot easier than what I have!!

Thanks for the help guys!