VERY FRUSTRATED!!! HAVE one last post before i loose it.

BOTTLEFED

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Neither one was probably bad until you connected it up with bad grounding. As soon as you turn the key, the bad grounding would have fried the VEC.
No matter, I'm glad you may have solved the problem.
I would take this time to go back through and recheck all your grounds, so this doesn't happen again.

Oh, and have Sean add the serial connector to the VEC (if it isn't already there) so you can connect to your laptop.
 
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Nates GTS Viper

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ok for those that were helping me in my quest to fix my gts i have a few updates. sean and mike at roe went through both vecs and found that the vec 3 had a burned out injector board and said that could be the problem. they then made two new harnesses for both the vecs and sent the vec 3 off to sweeden(i think) to have them fix it. so i got the new harness installed and hooked a vec two in that is checked out to be good. the car does run better with a lot less smoke but still has a little out of the exhaust. i had went through several sets of plugs while the car was dumping fuel and the last set i bought were stock replacements in the stock heat range. i let it idle for a while and took it up and down the driveway a few times to see how it would run. it drives almost like normal but doesnt like to much fuel at once. could this be bc of the plugs. ill be changing them out for the right ones today. i also looked at the scanner and took a couple notes.
ltft was -33.6
o2 1.02
o2 .84
map 5.0
i looked at all those at idle before i stopped working on it for the day.let me know what you all think. also the plug burn was alot better with the plugs being clean like almost new again with none of them being wet although i do think #3 was a little lean. thanks again for all the help.
 

RTTTTed

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Glad you found definite improvements.

If your engine is too rich when you throttle it, it will immediately slow or hesitate, then maybe pick up revs.

If your engine is too lean then when you throttle it the engine will start to rev, then hesitate or slow rpms.

You have the laptop hooked to your Vec connector? Under the box settings you can set the #3 cylinder richer. You can also adjust the main fuel for the complete engine tune under the % settings for the injector differences. At 10# boost with mods my setting is at 63%.

Yes, the plugs probably make a difference as well. Change plugs first and then Vec tune settings if that doesn't fix the tune.

Ted
 

BOTTLEFED

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if your LTFT was -33 then you will need to set your fuel trim
this must be done at idle with the car fully warmed up (closed loop)
 
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Nates GTS Viper

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thanks guys i checked and my tune says its at 64% fuel trim. how would i go about getting the ltft tuned and am i looking to get them to 0 like someone had mentioned earlier in this thread. also what type of vacume do you guys have at idle and when you rev it do you see any boost if so how much. thanks again
 

DVSGTS

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If you're -33%, you're too rich and its trying to pull back on the fuel, but it can only cut so much. Probably why you still have a little smoke and I bet it smells of gas pretty bad still too. Keep taking the % down in the base fuel calibration under the Fuel Options tab maybe 1 or 2 percent at a time until the LTFT starts to get more toward 0%. The rule is stock size/new size, but for me that was just a starting point and I had to go to a lower percentage in order for my LTFTs to be near zero at idle. Every car is different and you'll have to adjust for yours.

Sounds like you're making progress. Good luck and keep us updated!
 

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