Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

1991 firebird formula 350 tpi stalls when put in gear

Old 01-07-2019, 12:05 PM
  #1  
Junior Member
Thread Starter
 
Join Date: Jun 2018
Posts: 37
1991 firebird formula 350 tpi stalls when put in gear

Idles fine, stalls when put into reverse or drive. Can give it throttle when putting into drive to get it going, but stalls out if stopping at a light. Found a few threads that were similar, but nothing that solved my problem.
RandyNJ is offline  
Old 01-07-2019, 01:08 PM
  #2  
Supreme Member
 
Join Date: Jun 2002
Location: North East GA
Posts: 1,849
Car: 1989 Firebird
Engine: 5.7 LS1
Transmission: T56
Re: 1991 firebird formula 350 tpi stalls when put in gear

Sounds like the idle air control valve, if you give it a slight amount of gas pedal before you put it into gear does it stay running? if so that is typically the IAC, if it still stalls then it may be something with the timing advance.
Aviator857 is offline  
Old 01-07-2019, 01:41 PM
  #3  
Junior Member
Thread Starter
 
Join Date: Jun 2018
Posts: 37
Re: 1991 firebird formula 350 tpi stalls when put in gear

It stalls in gear if you let it idle.
RandyNJ is offline  
Old 01-07-2019, 02:32 PM
  #4  
Supreme Member
 
Join Date: Jun 2002
Location: North East GA
Posts: 1,849
Car: 1989 Firebird
Engine: 5.7 LS1
Transmission: T56
Re: 1991 firebird formula 350 tpi stalls when put in gear

Right but if you maintain 800 rpm in gear by pressing the brake and the gas pedal will it stay running. Or does it feel like it's trying to move forward?

If it seems to behave holding it at 800 rpm then IAC, if it is trying to do a burnout doing this then torque converter, if it sits there but runs roughly or dies timing.
Aviator857 is offline  
Old 01-09-2019, 07:56 AM
  #5  
Junior Member
Thread Starter
 
Join Date: Jun 2018
Posts: 37
Re: 1991 firebird formula 350 tpi stalls when put in gear

Looked into this more and found people saying the torque converter gets information from the vss. I didn't think it was related, but my speedometer stopped working the same time I noticed this issue. From what I understand the speedometer, cruise control, and the torque converter get affected by the vss? I'm not able to test cruise control because the car is at a shop. I'm just looking for answers to hopefully understand what's happening with my car. I don't recall a check engine light coming on though... I read if there's an issue with the vss it'd cause it to.

Last edited by RandyNJ; 01-09-2019 at 07:59 AM.
RandyNJ is offline  
Old 01-22-2019, 05:36 AM
  #6  
Junior Member
 
Join Date: Oct 2016
Location: SE Pennsylvania US
Posts: 44
Car: 1986 IROC-Z
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: Presently Open w/3.23 Ratio
Re: 1991 firebird formula 350 tpi stalls when put in gear

Originally Posted by RandyNJ View Post
Looked into this more and found people saying the torque converter gets information from the vss. I didn't think it was related, but my speedometer stopped working the same time I noticed this issue. From what I understand the speedometer, cruise control, and the torque converter get affected by the vss? I'm not able to test cruise control because the car is at a shop. I'm just looking for answers to hopefully understand what's happening with my car. I don't recall a check engine light coming on though... I read if there's an issue with the vss it'd cause it to.
Could be the torque converter/lockup (tcc) but generally you can`t overcome that by giving it more throttle. Once it locks up no matter what you do when stopped it dies. But there is usually a tcc fuse you can pull or a electrical connector on the tranny for the lockup signal you can pull to test.

I`m leaning more to the IAC or or timing (or both) as others mentioned. A sticking or wrongly connected EGR is also a possibility. Other things like a clogged cat or bad fuel pressure (FPR) or a clogged fuel filter could play a part but you would typically see higher RPM issues as well which I did not see mentioned.

Hope that helps
TAbracadabra is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
CNY89rs
TBI
3
09-15-2004 09:53 PM
ThraxXx
Tech / General Engine
5
07-01-2004 01:51 AM
peacefrogs72
Carburetors
11
04-10-2004 12:19 PM
FIRECHICKEN
Tech / General Engine
6
07-20-2002 11:23 PM
JPrevost
DIY PROM
0
05-10-2001 01:30 PM


Thread Tools
Search this Thread
Quick Reply: 1991 firebird formula 350 tpi stalls when put in gear


Advertising
Featured Sponsors
Vendor Directory

Contact Us - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: