TPI swap is T'ing me off

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Aug 22, 2003 | 04:19 PM
  #1  
After swapping all the stuff over i got the car to run half decent. The car was idleing at 1600 rpm's and would stumble if you stepped on the accelerator real hard. The IAC is set and the voltage is correct on the TPS but when unplugged brown and black wire to set my base timing the idle wouldn't drop at all, and the voltage was okay in the wire. So my nieghbor is trying to help me, he was playing with his car to get it to do the same thing mine was. So two weeks later he comes back and now i can't even get the car to start at all. Unless i keep spraying starting fluid in it. It was running two weeks ago, I checked the fuel pressure and it read like 40 to lbs the whole time i was cranking it over. My plugs are fine. This definitly was not worth the hassel IMO. Any idea's for me to try ?
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Aug 22, 2003 | 06:21 PM
  #2  
Try kicking the TPS up to .60 and then close the throttle blade to bring down the idle. Then you can reset the TPS back to stock.

One thing I noticed is you have a SD system with an aftermarket chip and what appears to be a stock low compression long block. (Please corrrect me on this if I am wrong.) You may have too much chip for your engine.....
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Aug 22, 2003 | 07:18 PM
  #3  
Actually i took the TPI set up off an 89' IROC which is MAF and using a stock chip out of a 350 IROC.
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Aug 22, 2003 | 08:21 PM
  #4  
From the looks of your signature it was a 91 Camaro and I saw a Stage II chip so I thought you had gone to a speed density setup in hope of keeping it legal visually.......

What have you done to the engine???
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Aug 22, 2003 | 08:41 PM
  #5  
Actually i had the stage 2 chip in when i was running the TBI set up.... There's nothing really done to the engine.. It was a 350 crate motor that i bought ATK. From what i understand it's pretty much close to a stock engine.
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Aug 22, 2003 | 08:55 PM
  #6  
Double check on the cam in the engine. What some people call stock might be pretty radical for an early model computer. If your timing is off, it will cause stumble problems. A cam like the ZZ4 needs to have at least ten degrees of timing (10 - 12 gets me through smog) and runs best with 16 degrees. This in comparison to the 6 degrees for a stock engine...... See what I mean?

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Aug 22, 2003 | 09:13 PM
  #7  
When it did run it was set at like 5 degrees. From what i understand to set the timing you have to unplug the brown and black wire to set it.. The rpm's should drop when unplugged, then you are supposed to set the timing and when you plug the wire back in the rpm's will raise . My problem is the rpm's seem to be hung up. It was ideling at 1600 RPM's and when i unplugged the wire it still ideled at 1600 RPM's.
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Aug 22, 2003 | 09:43 PM
  #8  
You adjust the throttle blade like I described above and it will change your idle. I actually had to do the opposite on my modified 350.....

Whoever you bought the stuff from could of had it adjusted for a modified engine.... Either that or someone played with it, screwed it up and then sold it because they couldn't figure it out....

Definately try adjusting the throttle blade, that should do it for you if that's the only problem. BTW, the idle doesn't always drop when the wires are disconnected. Depends on a lot of variables, like throttle position of the throttle blade, mechanical timing and idle injector pulse width. You also have a warm up function on the 89 computer that keeps the idle up high until the engine is warm.
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Aug 22, 2003 | 09:47 PM
  #9  
I'll give it shot if and when i can get it running again, gonna try some tomorrow i guess. Thanks
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