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Old 08-21-2011, 07:23 PM   #1
bark
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wire problems

ok, Ive built my harness using info from lt1 swap, I'm in mock up stage on my dbw 6.0l in a 76 stepper, I hooked it all up my pump ran for a second and my throttle body did a search phase, then has a kinda hum whistle sound to it, but does not open or close with throttle, also when I hook up my scanner It powers up but will not connect to the computer. I have not got my computer tune done yet, so not sure if that is why its not working, was just kinda hoping to fire it (not run, just fire. I know vats won't allow it), before I tear it all down for paint????

did I do something wrong, or will I have to wait for a tune before I bother trying?

thanks
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Old 08-26-2011, 12:05 PM   #2
68GMCCustom
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Re: wire problems

I'm not certain of this....but didn't think the DBW throttle bodies took input from the pedal until the engine starts? As far as the sound....don't have a clue. scanner shouldn't require a tune to activate?
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Old 08-26-2011, 04:13 PM   #3
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Re: wire problems

Everything sounds right. You can try to start it with VATS but it will pop a few times and die or maybe run for a few seconds.
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Old 08-27-2011, 02:47 PM   #4
BR3W CITY
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Re: wire problems

if vats is in it will turn over but will usually die before it catches. IF your fuel system is primed it will catch and fire a few *chugs* but die again. If your engine is non-stock, the pcm needs to "learn" the setup a bit so it probably won't catch.
I think 68GMC is right, the tb won't respond until its running, except for the test "Sweep" from key on.
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Old 09-14-2011, 01:47 PM   #5
bark
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Re: wire problems

been really busy around here, so havent had much time to work on it. I checked my daily driver (03 silverado) and with the key on if you step on the go pedal the TB will open, so? I will have to go throught my wireing, I`m hopeing it might just have a ground problem
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Old 10-02-2011, 10:48 AM   #6
bark
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Re: wire problems

so I got some time, I did some digging on my harness, and found that I missed a ground on the back of the engine (there is more then one), as soon as I hooked it up, hit the key the pump primed up. I cranked and it fired and died, then all of a sudden my scanner decided to link to the computer???? and I had an intake pressure code and bad MAF, grabbed another MAF erased codes, hit the key and it RUNS!!!!!!! found out that workhorse delivery vans don't have VATS

Now the only issue is my intake pressure code keeps coming back, which disables my DBW TB, as soon as I erase it, the throttle will operate for a bit????

have to find out more about intake pressure code, but it runs, so now its time for tear down and PAINT.... YAY!!!!!!
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Old 10-02-2011, 06:19 PM   #7
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Re: wire problems

Quote:
Originally Posted by bark View Post
so I got some time, I did some digging on my harness, and found that I missed a ground on the back of the engine (there is more then one), as soon as I hooked it up, hit the key the pump primed up. I cranked and it fired and died, then all of a sudden my scanner decided to link to the computer???? and I had an intake pressure code and bad MAF, grabbed another MAF erased codes, hit the key and it RUNS!!!!!!! found out that workhorse delivery vans don't have VATS

Now the only issue is my intake pressure code keeps coming back, which disables my DBW TB, as soon as I erase it, the throttle will operate for a bit????

have to find out more about intake pressure code, but it runs, so now its time for tear down and PAINT.... YAY!!!!!!
Whats the code number?
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Old 10-02-2011, 08:26 PM   #8
bark
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Re: wire problems

hmm I think it was p0107???

not sure tho will have to re scan it, cause I guaranty it will be back.
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Old 10-05-2011, 10:41 AM   #9
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Re: wire problems

Quote:
Originally Posted by bark View Post
hmm I think it was p0107???

not sure tho will have to re scan it, cause I guaranty it will be back.

P0107...MAP Sensor Circuit Low Voltage.

Possible Causes.
MAP sensor connector is damaged (check pins for damage, and for moisture)
MAP sensor signal circuit is shorted to ground
MAP sensor 5 volt circuit open between the sensor and PCM
MAP sensor has failed
PCM has failed

Check the MAP sensor voltage, Key On Engine Off.
Should have close to 5 V when near sea level.
Check the MAP sensor connection at the rear of the intake manifold.
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Old 10-08-2011, 12:45 AM   #10
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Re: wire problems

since your engine PCM doesn't have VATS does this mean you didn't have to have it re-programmed? You know what vehicle your donor came from?
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Old 10-09-2011, 11:02 PM   #11
bark
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Re: wire problems

Ya it's from a cube van, a 2005 workhorse still need to get a burn, cause I got rid of the emissions
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