Adjustable TPS Questions
Thread Starter
Team Owner
Joined: Jul 2004
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From: Hartford WI
Adjustable TPS Questions
In my 91, the TPS is not adjustable. Is there an adjustable one? IIRC, some models did have one which is adjustable.
I haven't read the code so I don't know but I thought someone said that in 91 it doesn't matter since the startup voltage is the idle voltage.
TIA for any help
I haven't read the code so I don't know but I thought someone said that in 91 it doesn't matter since the startup voltage is the idle voltage.
TIA for any help
Melting Slicks
Joined: Sep 2010
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there are many TPI FPR available!!!
I like the Holley version.. it has a big stainless dial to adjust your pressure...
most FPR have a 6mm bolt you need to use a wrench to adjust
my bad... Sorry your 91 TPS is non adjustable 89 and under is adjustable.. updated TB
I like the Holley version.. it has a big stainless dial to adjust your pressure...
most FPR have a 6mm bolt you need to use a wrench to adjust
my bad... Sorry your 91 TPS is non adjustable 89 and under is adjustable.. updated TB
Last edited by THE 383 admiral; Oct 14, 2010 at 05:09 PM.
Thread Starter
Team Owner
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From: Hartford WI
Race Director
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Unless it's different from my '89, the adjustment is performed by loosening the mounting screws them moving (rotating) it to get the correct closed voltage (.54 on mine). Then, full open voltage "is what it is", but should be over 4V.
Thread Starter
Team Owner
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From: Hartford WI
It is different from mine. I have the TPS with two holes. Some have 2 slots and are adjustable. Mine are not.
Thread Starter
Team Owner
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From: Hartford WI
http://www.eficonnection.com/eficonn..._pigtails.aspx
http://www.autozone.com/autozone/acc...ier=47133_0_0_
They seem to be the same?
http://www.autozone.com/autozone/acc...ier=47133_0_0_
They seem to be the same?
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From: Hartford WI
Safety Car
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Why are you wanting to make it adjustable? It has been a while. But I recall the non adjustable ones don't need to be adjusted. In that it gets reset every shutdown or start up. So, making it adjustable wouldn't change anything as I recall.
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Team Owner
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HOWEVER, since I have a different cam, heads, displacement, injectors, etc, etc that requires a higher idle, I have a higher commanded idle. AFAIK, if the TPS at startup is within a certain spec, it will accept it as the "rest" or idle position. What I don't know is the spec it is at. IOW, what if, after adjusting it to idle at say 900, the TPS voltage is say 0.8V or 0.3V and that is outside of the spec?
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You are correct that the 90-91 series will take the reading at startup and consider it to be the minimum position. If I had a stock setup, life is good. No adjustment needed.
HOWEVER, since I have a different cam, heads, displacement, injectors, etc, etc that requires a higher idle, I have a higher commanded idle. AFAIK, if the TPS at startup is within a certain spec, it will accept it as the "rest" or idle position. What I don't know is the spec it is at. IOW, what if, after adjusting it to idle at say 900, the TPS voltage is say 0.8V or 0.3V and that is outside of the spec?
HOWEVER, since I have a different cam, heads, displacement, injectors, etc, etc that requires a higher idle, I have a higher commanded idle. AFAIK, if the TPS at startup is within a certain spec, it will accept it as the "rest" or idle position. What I don't know is the spec it is at. IOW, what if, after adjusting it to idle at say 900, the TPS voltage is say 0.8V or 0.3V and that is outside of the spec?
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From: Hartford WI
Le Mans Master
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From: Kempner Texas
I've tried it both ways on my 96 which, from the factory is NON-ADJUSTABLE - and found no difference.
I tried it too on my son's 96 LT1 after his heads, rockers and cam change; same result.
Your mileage may vary.
Jake
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I believe there are TPS "high" and "low" codes that show up on the check engine light. I'd say drive the car and see if you get a TPS code on the check engine light. If you do, then you could try elongating the holes so you can adjust it somewhat before trying a new sensor.
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From: Hartford WI
Golen Engines website has the procedure and photos on how to convert a NON-ADJUSTABLE TPS into one that can be ADJUSTED. It involves elongating the holes from round to oblong.
I've tried it both ways on my 96 which, from the factory is NON-ADJUSTABLE - and found no difference.
I tried it too on my son's 96 LT1 after his heads, rockers and cam change; same result.
Your mileage may vary.
Jake
I've tried it both ways on my 96 which, from the factory is NON-ADJUSTABLE - and found no difference.
I tried it too on my son's 96 LT1 after his heads, rockers and cam change; same result.
Your mileage may vary.
Jake
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Team Owner
Joined: Jul 2004
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From: Hartford WI
Are you sure there even is a "normal" spec the TPS has to be in during start up for it to go by that as idle?
I believe there are TPS "high" and "low" codes that show up on the check engine light. I'd say drive the car and see if you get a TPS code on the check engine light. If you do, then you could try elongating the holes so you can adjust it somewhat before trying a new sensor.
I believe there are TPS "high" and "low" codes that show up on the check engine light. I'd say drive the car and see if you get a TPS code on the check engine light. If you do, then you could try elongating the holes so you can adjust it somewhat before trying a new sensor.
Wife likes to pull up as far as she can. At that time, I was on the "throne" and she pulled up while I was cleaning the TB and rolled over the TPS. Now I have to get a new one. 
Before I purchase I would like to see whether it makes a difference or not, hence the question. I know they have 2 codes that MIGHT be in my ECM tables. 21 and 22.
21 tps sensor out of range
22 tps sensor signal voltage low