WORN THROTTLE POSITION SENSOR ON '85?
Thread Starter
Instructor
Joined: Nov 2000
Posts: 140
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From: Grand Rapids MI
WORN THROTTLE POSITION SENSOR ON '85?
I have an 85 with 144,000 miles on it. Do not know if a previous owner has replaced stock TPS or not.
What are symptoms of a worn TPS?
I'm getting a hesitation/lurching in 4th gear (not in overdrive) at around 1400 rpms. It is not terrible, but certainly noticeable. Does not occur anytime else.
Any other ideas what this could be?
Thanks
grsteve
What are symptoms of a worn TPS?
I'm getting a hesitation/lurching in 4th gear (not in overdrive) at around 1400 rpms. It is not terrible, but certainly noticeable. Does not occur anytime else.
Any other ideas what this could be?
Thanks
grsteve
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: WORN THROTTLE POSITION SENSOR ON '85? (grsteve)
Is it lurching when you hammer it or just cruzin with light throttle?
You can check the TPS with a scannner or a DMM. Unplug the cable, connect the DMM probes between the middle and bottom pins and slowly open the throttle while observing the Ohms reading. It should change smoothly with no jumps or flat spots. You would also "wiggle" the linkage to see if the reading jumps.
You might also check the TPS base idle setting and your base timing. I've found that a base TPS setting of around .65Vdc gives a little better throttle response than the stock setting of .54Vdc. Then I like the base timing advanced as much as possible without knock retard or ping.
Also check spark plugs to assure you have full power available to avoid lugging.
You can check the TPS with a scannner or a DMM. Unplug the cable, connect the DMM probes between the middle and bottom pins and slowly open the throttle while observing the Ohms reading. It should change smoothly with no jumps or flat spots. You would also "wiggle" the linkage to see if the reading jumps.
You might also check the TPS base idle setting and your base timing. I've found that a base TPS setting of around .65Vdc gives a little better throttle response than the stock setting of .54Vdc. Then I like the base timing advanced as much as possible without knock retard or ping.
Also check spark plugs to assure you have full power available to avoid lugging.
Thread Starter
Instructor
Joined: Nov 2000
Posts: 140
Likes: 0
From: Grand Rapids MI
Re: WORN THROTTLE POSITION SENSOR ON '85? (65Z01)
just cruisin' is when it happens
I'm around .59 on the base idle setting
I have a digital meter, but would like to test it on an analog.
That way I could see if there is a drop or a spike along the way.
I'm fishing to see if anyone else has had anything similar.
I'm around .59 on the base idle setting
I have a digital meter, but would like to test it on an analog.
That way I could see if there is a drop or a spike along the way.
I'm fishing to see if anyone else has had anything similar.
