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

1989 GTA LB9/700R4 high idle and shuts off. 73k miles

Thread Tools
 
Search this Thread
 
Old 05-14-2015, 06:48 PM
  #1  
Member

Thread Starter
iTrader: (2)
 
92Forumla's Avatar
 
Join Date: Jul 2005
Location: Jacksonville, Florida
Posts: 141
Likes: 0
Received 0 Likes on 0 Posts
Car: 2017 2.0T Camaro / 1989 IROC
Engine: LTG / L98
Transmission: Tremec TR 3060 / 700R-4
1989 GTA LB9/700R4 high idle and shuts off. 73k miles

Hi all, have done a search and cannot find any new info to try to fix my issue. Once you start the engine, the idle automatically goes to 12-1500 rpm when its cold, over 1500 rpm when warm. Shift into gear and idle settles around 1000-1100 rpm. Seems to run well otherwise, but when it gets warm, you rev the engine slightly and it will die completely. The engine still will run liked a raped ape otherwise, but am having trouble figuring this issue out. So far I have:

Changed plugs- Ac Delco R45TS (gapped correctly)
Wires-Accel super stock
Cap and Rotor--AC Delco
Coil-- AC Delco
New CTS
New TPS--set at .54V and increases linear to 4.13V
Vader's IAC reset procedure
New thermostat--195F
All new Fel-Pro TPI intake gaskets
Checked and repaired any possible vaccum leaks
New fuel pump and filter

Also, I have tried to pull codes after everything listed above. I will get an SES light roughly 10 min into a steady drive but no change in running condition. I do have an ALDL cable and old laptop running WINALDL that I haven't yet tried to pull codes with but I did try the paperclip method and cannot get a code 12. SES light stays solid with jumper in place and KeyOn/EngineOff. Kinda stumped here and need a solution. I have never tried PROM tuning as I am a noob at that sort of thing but with the cable I can at least datalog. I have also taken a video of the engine warm and dying under light throttle that I can email or upload if need be. Thank you for any help that I receive! You guys have always been the kings of 3rd gen knowledge!
Old 05-16-2015, 11:12 AM
  #2  
Supreme Member

 
ploegi's Avatar
 
Join Date: Jul 1999
Location: Adrian, Mi, USA
Posts: 1,551
Likes: 0
Received 25 Likes on 20 Posts
Car: 1988 Pontiac Firebird Formula
Engine: 5.7 TPI
Transmission: 700R4
Re: 1989 GTA LB9/700R4 high idle and shuts off. 73k miles

Still sounds a lot like a vacuum leak...... disconnect the vacuum line from the brake booster, and plug it off.... see if anything improves.
Old 05-16-2015, 01:16 PM
  #3  
Member

Thread Starter
iTrader: (2)
 
92Forumla's Avatar
 
Join Date: Jul 2005
Location: Jacksonville, Florida
Posts: 141
Likes: 0
Received 0 Likes on 0 Posts
Car: 2017 2.0T Camaro / 1989 IROC
Engine: LTG / L98
Transmission: Tremec TR 3060 / 700R-4
Re: 1989 GTA LB9/700R4 high idle and shuts off. 73k miles

Originally Posted by ploegi
Still sounds a lot like a vacuum leak...... disconnect the vacuum line from the brake booster, and plug it off.... see if anything improves.
, that is what keeps bugging me. I hear no hissing or anything from around the intake. Also tried the old spray starting fluid around the intake and see if the idle picks up more and it doesn't. I'm just kind of lost at this point. Will re-check after I get off the water today and re-update.
Old 05-17-2015, 11:15 AM
  #4  
Member

Thread Starter
iTrader: (2)
 
92Forumla's Avatar
 
Join Date: Jul 2005
Location: Jacksonville, Florida
Posts: 141
Likes: 0
Received 0 Likes on 0 Posts
Car: 2017 2.0T Camaro / 1989 IROC
Engine: LTG / L98
Transmission: Tremec TR 3060 / 700R-4
Re: 1989 GTA LB9/700R4 high idle and shuts off. 73k miles

Nope, still does the same thing. Idle is still too high, starting to think I have a bad IAC..
Old 05-17-2015, 01:48 PM
  #5  
Supreme Member

 
ploegi's Avatar
 
Join Date: Jul 1999
Location: Adrian, Mi, USA
Posts: 1,551
Likes: 0
Received 25 Likes on 20 Posts
Car: 1988 Pontiac Firebird Formula
Engine: 5.7 TPI
Transmission: 700R4
Re: 1989 GTA LB9/700R4 high idle and shuts off. 73k miles

I think if you ground A and B on the ALDL terminal in the car, and turn the ignition on, it should run the IAC all the way closed. Try that, and then disconnect the IAC, and see if the engine idles really low.
Old 05-18-2015, 10:48 AM
  #6  
Member

Thread Starter
iTrader: (2)
 
92Forumla's Avatar
 
Join Date: Jul 2005
Location: Jacksonville, Florida
Posts: 141
Likes: 0
Received 0 Likes on 0 Posts
Car: 2017 2.0T Camaro / 1989 IROC
Engine: LTG / L98
Transmission: Tremec TR 3060 / 700R-4
Re: 1989 GTA LB9/700R4 high idle and shuts off. 73k miles

Very minor change in idle, idles about 1200 rpm in park. Around 850-900rpm in gear. Bad IAC? Also grounding the ports gives me no flashing SES light. Light stays solid with jumper in place.
Old 05-31-2015, 01:46 PM
  #7  
Member

Thread Starter
iTrader: (2)
 
92Forumla's Avatar
 
Join Date: Jul 2005
Location: Jacksonville, Florida
Posts: 141
Likes: 0
Received 0 Likes on 0 Posts
Car: 2017 2.0T Camaro / 1989 IROC
Engine: LTG / L98
Transmission: Tremec TR 3060 / 700R-4
Re: 1989 GTA LB9/700R4 high idle and shuts off. 73k miles

Any other ideas that I can try guys? This is a really frustrating issue to figure out. I threw an ALDL cable and a laptop at it to try and pull codes. It showed a MAF code, and had some really weird looking data showing up. I really hope the computer isn't dying, but I am out of things to try except for throwing parts on it.
Old 05-31-2015, 02:46 PM
  #8  
Senior Member

 
tealman92's Avatar
 
Join Date: Mar 2002
Location: Ontario, California
Posts: 998
Received 19 Likes on 16 Posts
Car: 1992 Z28
Engine: 383
Transmission: 700R4
Re: 1989 GTA LB9/700R4 high idle and shuts off. 73k miles

fuel pressure?
Old 06-01-2015, 09:09 AM
  #9  
Member

Thread Starter
iTrader: (2)
 
92Forumla's Avatar
 
Join Date: Jul 2005
Location: Jacksonville, Florida
Posts: 141
Likes: 0
Received 0 Likes on 0 Posts
Car: 2017 2.0T Camaro / 1989 IROC
Engine: LTG / L98
Transmission: Tremec TR 3060 / 700R-4
Re: 1989 GTA LB9/700R4 high idle and shuts off. 73k miles

Checked fuel pressure and it is 45 PSI at idle and driving moderately around the neighborhood.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
okfoz
History / Originality
195
03-09-2017 02:35 PM
Andrew6.688
TPI
10
12-13-2015 10:59 AM
kyleb24
Camaros for Sale
2
08-15-2015 08:24 AM
Fronzizzle
Electronics
2
08-09-2015 01:15 PM



Quick Reply: 1989 GTA LB9/700R4 high idle and shuts off. 73k miles



All times are GMT -5. The time now is 03:47 PM.