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Old Mar 28, 2005 | 10:48 AM
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From: dripping springs tx
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I ran the car for the first time with the TPI installed. It idled fine and when in gear it idled at 450 RPM's After driving it for a while when I would stop the engine would idle down and cut off. I could start it back up but if I took my foot off of the gas pedal it would cut off. I took the gas cap off of the gas tank and there was alot of pressure in the tank. I only have a supply and return line to the tank, Does the gas tank suppose to pressurize? My gas cap is vented.
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Old Mar 28, 2005 | 12:15 PM
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450 sounds a little low. You may need to adjust your TPS a bit. As far as fuel tank; I have a vented cap, plugged purge line, and just supply and return lines. I have not experienced any odd problems with idle. You do have VSS as I recall. If you can have/can borrow a scanner, make sure you are in park and make sure VSS is reading 0 (sitting still), make sure you are getting a TPS reading.
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Old Mar 28, 2005 | 12:21 PM
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From: dripping springs tx
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It idles fine in park and neutral. 700 RPM. No problem there. It is when it is in gear and I come to a stop that the engine quits. In drive is when it idles at 450 RPM. It will start back up but I have to keep the rpm up when I put it in gear or it will stall out.
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Old Mar 28, 2005 | 12:23 PM
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450 is real low.... I have mine set at 750. Any lower and it would crap out at idle. i di have a bigger cam, but 450 is low even for a stocker.

Are you running a GM ECU?
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Old Mar 28, 2005 | 01:48 PM
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From: dripping springs tx
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Yes I believe so. It is a 122727 which is water proof and heat resistant.
The setup I bought from someone that was selling it. It was a complete setup from FIC.It is also an automatic.
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Old Mar 28, 2005 | 03:52 PM
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I have mine idleing around 650 in gear and 900 in park
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Old Mar 28, 2005 | 09:16 PM
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Originally Posted by Veet 66
It idles fine in park and neutral. 700 RPM. No problem there. It is when it is in gear and I come to a stop that the engine quits. In drive is when it idles at 450 RPM. It will start back up but I have to keep the rpm up when I put it in gear or it will stall out.
Sounds like the computer doesn't know you are sitting still (false VSS signal) or the TPS is not adjusted. It could have been put on by them and not adjusted.
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Old Mar 28, 2005 | 09:25 PM
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are you using a park neutral switch? it tells ecu to raise rpm when you put in gear. i have a little pressure in tank but i used the canister and the pressure control valve. hope this helps gordy
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Old Mar 29, 2005 | 09:26 AM
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From: dripping springs tx
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I believe my problem is in setting the TPI up. I didn't know all the steps it takes just to set it up until now. Timing, jumping dianostic plug, setting the IAC and Air flow sensor. SHEE.
On the park/neutral switch I thought that it speeds up the idle in park and neutral only? When the switch is in park/neutral doesn't it ground out. Then when you put it in gear the switch circuit opens?
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Old Mar 29, 2005 | 10:03 AM
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Park neutral speeds up the idle in gear. It expects a ground to the ECM in park or neutral. If you ground this all the time, you will have issues-and it defeats the purpose of VSS input. You likely have to use a relay to get this ground signal from the neutral safety switch on the shifter.
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Old Mar 29, 2005 | 10:15 AM
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From: dripping springs tx
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I have a seperate park/neutral switch. It is mounted on the trans. and has a lever that is attached to the shifter rod.
Let me make sure I am reading this correctly. When the trans. is in park or neutral the switch is grounded. When it is in gear it is open. (no ground) If this is correct this is how it is working now.
Thanks for your help.
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Old Mar 29, 2005 | 09:07 PM
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Originally Posted by Veet 66
I have a seperate park/neutral switch. It is mounted on the trans. and has a lever that is attached to the shifter rod.
Let me make sure I am reading this correctly. When the trans. is in park or neutral the switch is grounded. When it is in gear it is open. (no ground) If this is correct this is how it is working now.
Thanks for your help.
Yes-ground in park or neutral. Open in Reverse and 1-4.
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Old Apr 3, 2005 | 11:11 AM
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From: dripping springs tx
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Thanks for the info. What has everyone been running the RPM in neutral? Also in gear?
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Old Apr 3, 2005 | 11:24 PM
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Originally Posted by Veet 66
Thanks for the info. What has everyone been running the RPM in neutral? Also in gear?
My tach is off, but I think about 700 idling and 600 in gear. Something in that neighborhood. Mine is stone stock cam and all.
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