TPI Tuned Port Injection discussion and questions. LB9 and L98 tech, porting, tuning, and bolt-on aftermarket products.
Sponsored by:
Sponsored by:

TPS bad?

Thread Tools
 
Search this Thread
 
Old 04-15-2010, 10:02 AM
  #1  
Junior Member
Thread Starter
 
NiteStar's Avatar
 
Join Date: Dec 2006
Posts: 67
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 formula w/t-tops
Engine: 350 (L98) 5.7 TPI
Transmission: 700-R4
Axle/Gears: 3.27
TPS bad?

I was hoping to get some opinions on this.
I am having a high/fluctuating idle. Sometimes a hesitation on go and even a jerking of the car (nothing too severe, but made me think that was a trannsmission problem) when driving down the road at times.

I am getting error code 22, which says "faulty tps" or "bad fuel pump relay".

Since I started getting the code, it'll go away for a couple days and then come back on. When on it will usally go off after accelerating and then when I get to a certain speed, it will come back on.

Do those symptoms say "bad tps" or am I really looking at a bad fuel pump relay?
Old 04-15-2010, 11:30 AM
  #2  
Supreme Member

iTrader: (17)
 
Chevy86 IROC-Z's Avatar
 
Join Date: May 2009
Location: Far West
Posts: 4,903
Received 30 Likes on 23 Posts
Car: 1986 Camaro Z28 IROC-Z
Engine: 350 Tuned Port Injection, for now.
Transmission: 700R4
Axle/Gears: Posi - 3.23
Re: TPS bad?

You may need to tune up your TPI system first. Read and perform the tune up process then let me know what the results in performance. Is your Formula Speed Density or Mass Air Flow?
Tune up link is here....
http://74.125.155.132/search?q=cache...&ct=clnk&gl=us

http://mpikas.blogspot.com/2008/08/t...june-2000.html
Old 04-15-2010, 12:39 PM
  #3  
Junior Member
Thread Starter
 
NiteStar's Avatar
 
Join Date: Dec 2006
Posts: 67
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 formula w/t-tops
Engine: 350 (L98) 5.7 TPI
Transmission: 700-R4
Axle/Gears: 3.27
Re: TPS bad?

It's a Speed Density system.

I've replaced the Ignition Module, Igntion Coil and battery. The spark plugs, wires, cap and rotor are about 6 months old.

Last edited by NiteStar; 04-15-2010 at 02:19 PM.
Old 04-15-2010, 01:58 PM
  #4  
Junior Member
Thread Starter
 
NiteStar's Avatar
 
Join Date: Dec 2006
Posts: 67
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 formula w/t-tops
Engine: 350 (L98) 5.7 TPI
Transmission: 700-R4
Axle/Gears: 3.27
Re: TPS bad?

btw another symptom/problem is...

Just now it was idling very high @ 1200 rpm. When it does this, sometimes it'll come down after 5-10 minutes or I just shut it off. I pressed the gas peddle a quick 2X and noticed it can help make it go down to idle @ 700. After a minute longer it started jumping down to 3-400 rpm and fluctuation and almost stalling. I tried pressing the gas pedal but it did nothing. Smoke was coming out the back (I assume it was flooding so it was gas). I'm scared to drive it. Seemed though like just shutting off the car and starting right back up, made it go back to normal.
Old 04-15-2010, 04:19 PM
  #5  
Supreme Member

iTrader: (17)
 
Chevy86 IROC-Z's Avatar
 
Join Date: May 2009
Location: Far West
Posts: 4,903
Received 30 Likes on 23 Posts
Car: 1986 Camaro Z28 IROC-Z
Engine: 350 Tuned Port Injection, for now.
Transmission: 700R4
Axle/Gears: Posi - 3.23
Re: TPS bad?

Sure sounds like a bad TPS. All that it does is it tells the ECM that the throttle plates are open and to adjust how much fuel to inject via fuel injectors. So if the TPS is faulty, it may send a false voltage reading to the ECM and the ECM will then think that the gas peddle is being pressed which them the ECM adjusts the fuel injectors and will begin to throw more fuel while there is insufficient air thus causing bad idle or stalling because of the bad air/fuel ratio mixture. Buy a new TPS and adjust it. Its only about $20. Im almost certain thats whats causing the issue.
Old 04-15-2010, 05:14 PM
  #6  
Junior Member
Thread Starter
 
NiteStar's Avatar
 
Join Date: Dec 2006
Posts: 67
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 formula w/t-tops
Engine: 350 (L98) 5.7 TPI
Transmission: 700-R4
Axle/Gears: 3.27
Re: TPS bad?

I hope so Chevy. I have the TPS on order to pick up first thing tomorrow. I'll let u know either way. Right now, I'm afraid to drive it for fear it dies while driving. It happened this morning and it was like I ran out of gas, but of course I hadn't.
Old 04-21-2010, 02:04 AM
  #7  
Junior Member
Thread Starter
 
NiteStar's Avatar
 
Join Date: Dec 2006
Posts: 67
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 formula w/t-tops
Engine: 350 (L98) 5.7 TPI
Transmission: 700-R4
Axle/Gears: 3.27
Re: TPS bad?

Just wanted you to know Chevy86, that changing the TPS fixed my high idle fluctuations and the other problems I mentioned. Thanks for the help.
Old 04-21-2010, 01:27 PM
  #8  
Supreme Member

iTrader: (17)
 
Chevy86 IROC-Z's Avatar
 
Join Date: May 2009
Location: Far West
Posts: 4,903
Received 30 Likes on 23 Posts
Car: 1986 Camaro Z28 IROC-Z
Engine: 350 Tuned Port Injection, for now.
Transmission: 700R4
Axle/Gears: Posi - 3.23
Re: TPS bad?

Very, Nice bro. Im happy that you nailed the issue. Alright bro, take it easy and drive safe. Peace .
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
92firebirdguy
TBI
59
09-01-2016 07:53 AM
BumpaD82
Tech / General Engine
37
02-26-2016 02:57 PM
3rdgenkindagal
Tech / General Engine
15
09-13-2015 02:02 PM
earlpote
TPI
9
09-12-2015 11:55 AM



Quick Reply: TPS bad?



All times are GMT -5. The time now is 06:08 AM.