LQ9 swap
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Teching In
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From: Olds Iowa
LQ9 swap I bought a 98 Firebird that had an 03 Escalade 6.0 put in. Ever since I have had it the SES flashes under load and acts like its in limp mode. Took it to have a scan done and they found #1 was dead. Changed plug/wire/coil/injector. It doesn't put a hard code in pcm. Every once in a while I can get my handheld to pull a P0200. I ohmed all injectors and they are within .2 of each other. New plugs and wires. The noid shows all injectors are getting power. Harness isnt rubbing anywhere I could see. It's running the Caddy pcm I believe with the 98 harness. Any other Ideas??
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From: Olds Iowa
The fuel pressure is solid 55#. How do you check to see if the cats are clogged? Pull the y pipe? There is a noise coming from the drivers side when on the throttle.
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From: Olds Iowa
So I found this site http://lt1swap.com/2001_PCM_CONN_PINOUT.htm . It says the 98 has a different pin out than 99-02. Could I have the wrong ecm for the swap? I didn't do the swap so how do I check the ecm? I was under the impression it had the Escalade ecm. The harnes still has the egr plug so I assume it's a 98 harness. Am I on the right track or keep looking?
The '98 PCM is all cast aluminium with cooling fins on both sides. The layer boxes have no fins, and a sheet metal cover on one side. Look nothing alike.
There would be no rational reason to put the later PCM in it.
There would be no rational reason to put the later PCM in it.
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From: Olds Iowa
Ok so when I took it in to be scanned the tech put in a 98 Firebird and couldn't get any feedback. He changed the vehicle to 03 Escalade and got the error codes on the misfires. So if its running the 98 pcm it must have had some kind of tune in it to delete egr correct? Ill look at the pcm tommorow to see which it is. Thanks for the input. I appreciate it.
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Verdad Gallardo Thread Starter
Teching In
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From: Olds Iowa
Thread Starter
Teching In
Joined: Dec 2010
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From: Olds Iowa
This pcm has 4 fins on one side and a sheet metal cover on the other. I guess maybe they repinned the harness? Ran the vin and it is to a 2000 silverado.
Last edited by dragpny; Dec 22, 2013 at 11:27 AM. Reason: add
Thread Starter
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From: Olds Iowa
So I have a question. I was checking the injector plugs to see if I had a shorted ground. I checked them key off test light pos side of batteryand the left wire on the plug lit up so it was grounded. I checked the right wire and nothing. So I hooked the test light to groungd nothing either wire so I assume thats good. I check the same wire key on and the left wire now has power and the right wire is still nothing. Is this right?
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From: Harrison Twp. MI
with the key on you should have 12v at all injectors the pcm supplies the ground, make sure all injectors are plugged in also check for any breaks/exposed wires between pcm and injectors if none ad all checks out problem is in the pcm
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From: Olds Iowa
I pulled the harness and checked all the wires. I think its in the pcm also. I am ordering a new on from Frost.
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From: Olds Iowa
Got my new PCM from Steve. The P0200 is gone. Now I have a P0101 and P0300. I think it has a bad Mass air sensor. But one thing it does now is as soon as I start it the cooling fans run on high and don't shut off. Any ideas on either issues.
