Does an 89 vette have an adjustable tps?
Burning Brakes
Joined: Jun 2003
Posts: 1,229
Likes: 1
Re: Does an 89 vette have an adjustable tps? (calebchoson)
Yes, it is adjustable its the AIC that was not adjustable on later L98 engines.
There are two screws on the side of the TPS
You might want to read this post of the tech tips section,
https://www.corvetteforum.com/techti...D=55&TopicID=2
There are two screws on the side of the TPS
You might want to read this post of the tech tips section,
https://www.corvetteforum.com/techti...D=55&TopicID=2
Burning Brakes
Joined: Jun 2003
Posts: 1,229
Likes: 1
Re: Does an 89 vette have an adjustable tps? (TheStef)
I just read the tech tip section and I confused myself 
Its says that later L98 don't have adjustable TPS, but I know mine is adjustable since I can see the two screws on the side of it to adjust it.
Can someone help ??
Its says that later L98 don't have adjustable TPS, but I know mine is adjustable since I can see the two screws on the side of it to adjust it.
Can someone help ??
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Re: Does an 89 vette have an adjustable tps? (TheStef)
I believe 90 was the first year that the TPS became NON adjustable. The ECM controls the voltage.
Up through the 89 model year, the TPS should be slotted where the two screws pass through to bolt it to the TB. Loosening those screws allows the TPS to be swiveled up/down/backward and forward.
This movement changes the voltage readings.
Jake
Up through the 89 model year, the TPS should be slotted where the two screws pass through to bolt it to the TB. Loosening those screws allows the TPS to be swiveled up/down/backward and forward.
This movement changes the voltage readings.
Jake
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Does an 89 vette have an adjustable tps? (JAKE)
The TPS was adjustable on '85-'89 L98s; beginning in '90 the ECM "learned" idle and WOT voltages so the two screw holes were no longer slotted.
On all L98s the ECM uses the IAC to control idle so base idle needs to be set correctly (450 RPM) for proper operation.
[Modified by 65Z01, 3:49 PM 7/5/2004]
Le Mans Master
Joined: Aug 2000
Posts: 7,760
Likes: 0
From: Lost in the mountains of TN
Re: Does an 89 vette have an adjustable tps? (PUREC4)
Make sure you have an Ohm meter before trying to adjust it. Has to be in range, or things get worse. 
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
