TPS Adjustment?
Thread Starter
8th Gear
Joined: Feb 2013
Posts: 8
Likes: 0
TPS Adjustment?
1993 Corvette 40th Anniversary
LT1 5.7 L
Vin P (8th character)
Stock Engine (absolutely no mods...
yet)
Good afternoon. This is my first post on this forum and am confident we will figure out this situation I have. Today was such a nice day to take her out for a spin, but we have spent the better part of the day with the hood up and tempers smoldering. LOL We have searched on here and Google and to no avail we can't seem to find a solution to this issue. We just acquired this little beauty and she is in fantastic condition. We took her for a bath and an engine clean and the wonderful people at the detail shop power washed the engine and soaked the opti spark. After replacing the opti spark and water pump (preventative maint) most of the codes were resolved. However, the TPS was not acting right and had a code 21 and 22 which led us to the parts store for a new TPS. After installing the new TPS, we resolved the code 22 (low voltage) but still have a code 21. With the TPS being spring loaded I am not sure how to adjust it to bring the volume down from 4.34 to .54... Am I missing something?
LT1 5.7 L
Vin P (8th character)
Stock Engine (absolutely no mods...
yet)Good afternoon. This is my first post on this forum and am confident we will figure out this situation I have. Today was such a nice day to take her out for a spin, but we have spent the better part of the day with the hood up and tempers smoldering. LOL We have searched on here and Google and to no avail we can't seem to find a solution to this issue. We just acquired this little beauty and she is in fantastic condition. We took her for a bath and an engine clean and the wonderful people at the detail shop power washed the engine and soaked the opti spark. After replacing the opti spark and water pump (preventative maint) most of the codes were resolved. However, the TPS was not acting right and had a code 21 and 22 which led us to the parts store for a new TPS. After installing the new TPS, we resolved the code 22 (low voltage) but still have a code 21. With the TPS being spring loaded I am not sure how to adjust it to bring the volume down from 4.34 to .54... Am I missing something?
Thread Starter
8th Gear
Joined: Feb 2013
Posts: 8
Likes: 0
I am headed to get TPS #2 since this new one has a spring issue... but there is only one way to put it in if I am not mistaken. I like to think I am pretty mechanically inclined, and have replaced a few TPS' but this is ridiculous. We also have a 95 Z28 and what looks like the same TPS for somewhat the same LT1 set up, the Z28 did not the have issues like the vette is causing now. Just sayin.
We also have a 95 Z28 and what looks like the same TPS for somewhat the same LT1 set up, the Z28 did not the have issues like the vette is causing now. Just sayin.
Thread Starter
8th Gear
Joined: Feb 2013
Posts: 8
Likes: 0
Good Morning. We would like to thank the both of you (JackDidley and nickgost) for your responses.
We are not opposed to aftermarket parts on certain applications; however, we went to the dealership for the OEM TPS after 2 failed sensors from local parts store. Our Code 21 was resolved, but while connected to the computer the TPS read .74 and we got it down to .66. At idle, the TPS is currently reading .68 and that let us realize there is a 2 hundrenths of a difference (.66) with the ignition on, engine off. JackDidley, you said that .54 was perfect and we are going to get this TPS to .54 (which I am going to set it at .52 so I can achieve that .54). Where we are curious is if there is a spectrum to have this TPS operate perfectly... i.e. .50 - .75? Thank you again for your assistance.
We are not opposed to aftermarket parts on certain applications; however, we went to the dealership for the OEM TPS after 2 failed sensors from local parts store. Our Code 21 was resolved, but while connected to the computer the TPS read .74 and we got it down to .66. At idle, the TPS is currently reading .68 and that let us realize there is a 2 hundrenths of a difference (.66) with the ignition on, engine off. JackDidley, you said that .54 was perfect and we are going to get this TPS to .54 (which I am going to set it at .52 so I can achieve that .54). Where we are curious is if there is a spectrum to have this TPS operate perfectly... i.e. .50 - .75? Thank you again for your assistance.
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 41
From: Baltimore, MD USA
The voltage reading should be between .3 to .9 volts with the throttle body closed.
Most people do not have access to a Tech 1 tester so they can't perform the TP Learn procedure (used for the ABS/TCS). It doesn't appear to cause any problems if you don't do the procedure.
Most people do not have access to a Tech 1 tester so they can't perform the TP Learn procedure (used for the ABS/TCS). It doesn't appear to cause any problems if you don't do the procedure.
Last edited by Hooked on Vettes; Feb 19, 2013 at 01:04 PM.
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