08 G8 GT. No crank, no start. "Contact dealer" message. No OBD-2 contact/resonse
10-20-2016, 07:35 AM
#1
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08 G8 GT. No crank, no start. "Contact dealer" message. No OBD-2 contact/resonse Hello all,
I recently got my car back on the road after an engine swap, and when I got the car running I received a P0171 code(when the car was running). It said the car was running lean, but I was dumping tons of fuel, I could smell it coming from out of the tail pipe. I went through about 4 gallons of gas in 32 miles. I also had erratic and prolonged gear driving from the transmission(shifts were normal, it just held gears much longer than normal). My throttle response was also effected. I even went full throttle to test the car, and it felt like I was part throttle. Yesterday I found a vacuum leak, plugged it, and I went for a test drive. After about 10 seconds, my gauges go dead, I get a "contact dealer" message, but the car was driving seemingly as it was before the vacuum leak but after the engine swap. I park it, check for leaks, smoke or anything abnormal, nothing. I go to start the car, nothing. No crank, no click, nothing. I checked all of my fuses, they're good. I tried to scan the car, I can't get a signal or response. I check power to the starter, nothing. Something is not sending a signal to my starter. I did some research on a phase similar to my title, and a lot of people are saying it's the computer(ecm?). Hopefully this would explain my fueling issues and shift points and throttle position. As for my fueling issue My fuel trims were about 24 for number 1(bank 1 I assume?), and number two was about 8.0-12.
What it sounds like, I have a vacuum issue and a ecm issue. Maybe they're connected, I don't know. I want to at least see if I can get the car back to at least starting and running. I will be pulling the ecm and testing the pin outs on it tomorrow or during the weekend, hopefully someone can shed some light on my problem. Does anyone have a diagram or chart on the ECM pins?
I recently got my car back on the road after an engine swap, and when I got the car running I received a P0171 code(when the car was running). It said the car was running lean, but I was dumping tons of fuel, I could smell it coming from out of the tail pipe. I went through about 4 gallons of gas in 32 miles. I also had erratic and prolonged gear driving from the transmission(shifts were normal, it just held gears much longer than normal). My throttle response was also effected. I even went full throttle to test the car, and it felt like I was part throttle. Yesterday I found a vacuum leak, plugged it, and I went for a test drive. After about 10 seconds, my gauges go dead, I get a "contact dealer" message, but the car was driving seemingly as it was before the vacuum leak but after the engine swap. I park it, check for leaks, smoke or anything abnormal, nothing. I go to start the car, nothing. No crank, no click, nothing. I checked all of my fuses, they're good. I tried to scan the car, I can't get a signal or response. I check power to the starter, nothing. Something is not sending a signal to my starter. I did some research on a phase similar to my title, and a lot of people are saying it's the computer(ecm?). Hopefully this would explain my fueling issues and shift points and throttle position. As for my fueling issue My fuel trims were about 24 for number 1(bank 1 I assume?), and number two was about 8.0-12.
What it sounds like, I have a vacuum issue and a ecm issue. Maybe they're connected, I don't know. I want to at least see if I can get the car back to at least starting and running. I will be pulling the ecm and testing the pin outs on it tomorrow or during the weekend, hopefully someone can shed some light on my problem. Does anyone have a diagram or chart on the ECM pins?
10-20-2016, 09:10 AM
#2
Check that ECM connectors are fully seated and making good contact.
Remove them, clean and inspect. Install them again and test.
If you can't scan the ECM then it may be bad.
Remove them, clean and inspect. Install them again and test.
If you can't scan the ECM then it may be bad.
10-21-2016, 01:24 PM
#4
Launching!
I have a G8 GT also. Check the battery and alternator. You havent indicated if you check that yet.
10-24-2016, 08:59 AM
#5
Staging Lane
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If I bought a used ECM from another 2008 GT, and put it in, would it work? Or would the car bug out and throw a security code or show the same symptoms? It looks like the ECM is bad, and the dealership wants $278.19 for it, and $125 to reprogram it. I know in my S10 I got a mail order tune, and I needed a "CASE relearn", but the truck operated as normal. I see used ECM's go for $40 on ebay, and assuming it's in good shape, I wonder if I can just throw it in to at least get the car to perform basic operations so my tuner can work on it without paying a lot of money for a new ECM and programming.
10-24-2016, 09:31 AM
#6
If I bought a used ECM from another 2008 GT, and put it in, would it work? Or would the car bug out and throw a security code or show the same symptoms? It looks like the ECM is bad, and the dealership wants $278.19 for it, and $125 to reprogram it. I know in my S10 I got a mail order tune, and I needed a "CASE relearn", but the truck operated as normal. I see used ECM's go for $40 on ebay, and assuming it's in good shape, I wonder if I can just throw it in to at least get the car to perform basic operations so my tuner can work on it without paying a lot of money for a new ECM and programming.
As for the pinout, google E38 ECM and lots of diagrams come up.
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10-25-2016, 03:57 PM
#8
Launching!