Timing done. Reset TPS?
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From: Victoria Harbour
Timing done. Reset TPS?
Hi:
Just set the timing (way off). Now wondering if i need to reset the TPS. I did reset it with the timing way retard.
Then noticed the timing was way WAY off.
Just set the timing (way off). Now wondering if i need to reset the TPS. I did reset it with the timing way retard.
Then noticed the timing was way WAY off.
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From: Overland Park Kansas
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The TPS voltage is a measure of how open/closed the throttle blades are. IOW, it's a reference point for the motor to "know" where the blades are.
Changing the timing does NOT alter that and would not require the TPS to be reset. Once it's on .54mV (or whatever setting your car requires), it should stay there unless you alter the idle stop screw or the TPS itself wiggles loose.
Changing the timing does NOT alter that and would not require the TPS to be reset. Once it's on .54mV (or whatever setting your car requires), it should stay there unless you alter the idle stop screw or the TPS itself wiggles loose.
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From: Victoria Harbour
The TPS voltage is a measure of how open/closed the throttle blades are. IOW, it's a reference point for the motor to "know" where the blades are.
Changing the timing does NOT alter that and would not require the TPS to be reset. Once it's on .54mV (or whatever setting your car requires), it should stay there unless you alter the idle stop screw or the TPS itself wiggles loose.
Changing the timing does NOT alter that and would not require the TPS to be reset. Once it's on .54mV (or whatever setting your car requires), it should stay there unless you alter the idle stop screw or the TPS itself wiggles loose.
Im wondering if now i have to re-adjust the idle screw to 400rpm's in drive... then set the TPS again.
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From: Overland Park Kansas
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Why'd you need to set the timing? Who changed it in the first place? If it's set to 6-deg BTDC w/o the EST connector plugged in, you're good to go. (IOW, you would have put the idle BACK where it was supposed to be.) If not just set to 6-deg, put it there, get some gear to do tuning, or get a chip burned.
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From: Merritt Ils Fl
Benny you can not just play with the idle screw to change idle speed. Your ECM is expecting timing to be 6 BTDC, TPS at .54 volts and idle at whatever your engine/trans combo calls for. Without these values the ECM will continue to make fuel/ignition changes based on false data generally not to your satisfaction. I suggest you check Tech Tips for the correct procedures and go from there. Both you and your Corvette will be happier.
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From: Mystic CT
Are you sure the outter ring on he damper did not spin / slip so your timing marks are not correct? It is a pretty common thing. What inspired you to check or change the timing how was the car running before the change?
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From: Victoria Harbour
The car was running slow, very unresponsive, and ran out of power in High RPMS.
I think the timing has been out for years.
Honestly i just never looked there because i was assuming it was set right in the start (when rebuilt and installed).
Now that the timing is right, the car has 2x the power. What a difference.
I think the timing has been out for years.
Honestly i just never looked there because i was assuming it was set right in the start (when rebuilt and installed).
Now that the timing is right, the car has 2x the power. What a difference.
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From: Overland Park Kansas
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And, your car should be running poorly (at least in some rpm ranges) if it's bad.
Edit: Because there is an ESC system (elec spark sys) that monitors/retards timing that's too advanced, you COULD be very advanced but still getting most of that extra timing pulled back out. It will retard up to about 20-deg of timing (depending on rpms). That's probably about how much you advanced the timing I bet.
In some places, it might run better but that doesn't me it's "right". You NEED to check this!!!
Last edited by GREGGPENN; Oct 1, 2010 at 07:09 PM.
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From: Overland Park Kansas
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If you find you're balancer is O.K. (and that the motor's been way off since your rebuild),,,It can't hurt to check the idle. If the timing was set that far off, maybe the idle is too. OTOH, a stock rebuild shouldn't really need much (if any) alteration on the TB to be close.
If the stock TB hasn't been reset, there should be a metal cap pressed in on top of the idle screw.
If the stock TB hasn't been reset, there should be a metal cap pressed in on top of the idle screw.
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From: Victoria Harbour
If you find you're balancer is O.K. (and that the motor's been way off since your rebuild),,,It can't hurt to check the idle. If the timing was set that far off, maybe the idle is too. OTOH, a stock rebuild shouldn't really need much (if any) alteration on the TB to be close.
If the stock TB hasn't been reset, there should be a metal cap pressed in on top of the idle screw.
If the stock TB hasn't been reset, there should be a metal cap pressed in on top of the idle screw.
I also purchased a Porsche 930 so when i got the vette back(1year later). I just thought "mabey" i didnt realize that the Vette was slowish.
After all i installed some performance goodies for the vette.
Now the Vette is back in the game !!
