Almost Stalls After Starting - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Reply
 
 
 
Thread Tools Search this Thread
Old 08-24-2004, 12:00 AM   #1
Junior Member
Posts like a V-Tak
Thread Starter
 
Join Date: Mar 2003
Location: PA
Posts: 29
Thanks: 0
Thanked 0 Times in 0 Posts
jimg83 is on a distinguished road
Default Almost Stalls After Starting

I have a 93 Bonneville SE with 118,500 miles on it. It still runs great, but I have a concern with the way it starts. Immediately after starting, it seems like it wants to stall... the RPM'* drop all of the way down to 500 and then it goes back up to around 1,500 RPM'* (where it idles). When it drops down to 500 RPM'*, it gets real rough and sounds like it is stalling. The colder it is outside, the more pronounced it is. If the car has been driven recently before restarting, it barely does this at all. The whole start - drop to 500 - and back up to normal idle only takes about a couple of seconds. It only seems like it is going to stall for maybe 1-2 seconds, but it is rough enough that you can feel it and hear it. If it is really warm outside, the semi-stall is not as pronounced. I have been lucky and it has not actually been stalling, but I am concerned as to what it will do in the upcoming winter when it is actually cold outside. Does anyone have any ideas? I appreciate anything you can think of. Thanks


Jim
jimg83 is offline   Reply With Quote
Old 08-24-2004, 01:45 AM   #2
Senior Member
Certified Car Nut
 
Join Date: Jun 2003
Posts: 15,928
Thanks: 0
Thanked 0 Times in 0 Posts
BonneMeMN is on a distinguished road
Default

What about when coasting down hills or on the road with no throttle input?
BonneMeMN is offline   Reply With Quote
Old 08-24-2004, 02:21 AM   #3
Senior Member
Posts like a Turbo
 
Join Date: Dec 2003
Location: Monroe, MI
Posts: 230
Thanks: 0
Thanked 0 Times in 0 Posts
1994ta is on a distinguished road
Default

mine does the same thing, no hill problems though.. the only code im throwing is for the cam sensor.
1994ta is offline   Reply With Quote
Old 08-24-2004, 09:45 AM   #4
Senior Member
Posts like a Northstar
 
Join Date: Mar 2003
Location: Brewerton NY
Posts: 551
Thanks: 0
Thanked 0 Times in 0 Posts
karfreek is on a distinguished road
Default

I have experienced this with the TPI engines on the F-Bodies. The common fix is a coolent temp sensor. Sensor is giving the PCM the wrong temp so it does not know to kick the idle and mixture up.

A good check is to disconnect the plug to it and start it when its cold. The default reading should go to -40 (or something close) and tell the PCM to start like its cold.

Jay
karfreek is offline   Reply With Quote
Old 08-24-2004, 11:36 AM   #5
Senior Member
True Car Nut
 
Join Date: Jan 2004
Location: Chicago,IL MWBF '04 SURVIVOR MWBF '05 SURVIVOR Napa Manager
Posts: 3,955
Thanks: 0
Thanked 0 Times in 0 Posts
Kennginn is on a distinguished road
Default

Quote:
Originally Posted by karfreek
I have experienced this with the TPI engines on the F-Bodies. The common fix is a coolent temp sensor. Sensor is giving the PCM the wrong temp so it does not know to kick the idle and mixture up.

A good check is to disconnect the plug to it and start it when its cold. The default reading should go to -40 (or something close) and tell the PCM to start like its cold.

Jay
y would the coolant temp sensor deal with idle i am jus curious thats all
Kennginn is offline   Reply With Quote
Old 08-24-2004, 11:50 AM   #6
Senior Member
Posts like a Northstar
 
Join Date: Mar 2003
Location: Brewerton NY
Posts: 551
Thanks: 0
Thanked 0 Times in 0 Posts
karfreek is on a distinguished road
Default

It would if it was cold. It uses the temp sensor to adjust the idle and mixture when the car is cold. A car starting cold, (Ex; sat overnight) needs a high idle and rich fuel mixture to run for the first few minutes until it starts to warm. Kinda like starting a lawn mower or snow blower. Basicly, if the the sensor is telling the car that it is warm, when it isnt iIts like trying to start a carbed car without the choke set, it may start, but not run right until warm.

Bad coolent sensors can also cause driveability and performance problems. They only cost $8 @ NAPA, so it is not a ton of $$$ lost if it isnt the problem.

When my Trans Am had a bad coolent temp sensor, it would start, then drop the RPM, to 600, then surge back to 1,200, then down to 600, then back. Also it would bog down until it was warm when trying to accelerate. Now that it is fixed it starts and goes to 1,200 until warm and then cuts to 500-600.

There is a VERY GOOD article in the newest GMHTP, (silver Z28 on the cover) it covers the GM Coolent temp sensor and the roll it plays in the GM engine management system.

Jay
karfreek is offline   Reply With Quote
Old 08-24-2004, 11:56 AM   #7
Senior Member
Posts like a Northstar
 
Join Date: Jan 2002
Location: southern California
Posts: 538
Thanks: 0
Thanked 0 Times in 0 Posts
billha is on a distinguished road
Default

Sounds like maybe the throttle body needs cleaning.
billha is offline   Reply With Quote
Old 08-24-2004, 11:58 AM   #8
Senior Member
True Car Nut
 
Join Date: Jan 2004
Location: Chicago,IL MWBF '04 SURVIVOR MWBF '05 SURVIVOR Napa Manager
Posts: 3,955
Thanks: 0
Thanked 0 Times in 0 Posts
Kennginn is on a distinguished road
Default

Quote:
Originally Posted by karfreek
It would if it was cold. It uses the temp sensor to adjust the idle and mixture when the car is cold. A car starting cold, (Ex; sat overnight) needs a high idle and rich fuel mixture to run for the first few minutes until it starts to warm. Kinda like starting a lawn mower or snow blower. Basicly, if the the sensor is telling the car that it is warm, when it isnt iIts like trying to start a carbed car without the choke set, it may start, but not run right until warm.

Bad coolent sensors can also cause driveability and performance problems. They only cost $8 @ NAPA, so it is not a ton of $$$ lost if it isnt the problem.

When my Trans Am had a bad coolent temp sensor, it would start, then drop the RPM, to 600, then surge back to 1,200, then down to 600, then back. Also it would bog down until it was warm when trying to accelerate. Now that it is fixed it starts and goes to 1,200 until warm and then cuts to 500-600.

There is a VERY GOOD article in the newest GMHTP, (silver Z28 on the cover) it covers the GM Coolent temp sensor and the roll it plays in the GM engine management system.

Jay

thanks a lot jay
Kennginn is offline   Reply With Quote
Old 08-24-2004, 12:01 PM   #9
Senior Member
Posts like a Northstar
 
Join Date: Mar 2003
Location: Brewerton NY
Posts: 551
Thanks: 0
Thanked 0 Times in 0 Posts
karfreek is on a distinguished road
Default

Quote:
Originally Posted by Kennginn
Quote:
Originally Posted by karfreek
It would if it was cold. It uses the temp sensor to adjust the idle and mixture when the car is cold. A car starting cold, (Ex; sat overnight) needs a high idle and rich fuel mixture to run for the first few minutes until it starts to warm. Kinda like starting a lawn mower or snow blower. Basicly, if the the sensor is telling the car that it is warm, when it isnt iIts like trying to start a carbed car without the choke set, it may start, but not run right until warm.

Bad coolent sensors can also cause driveability and performance problems. They only cost $8 @ NAPA, so it is not a ton of $$$ lost if it isnt the problem.

When my Trans Am had a bad coolent temp sensor, it would start, then drop the RPM, to 600, then surge back to 1,200, then down to 600, then back. Also it would bog down until it was warm when trying to accelerate. Now that it is fixed it starts and goes to 1,200 until warm and then cuts to 500-600.

There is a VERY GOOD article in the newest GMHTP, (silver Z28 on the cover) it covers the GM Coolent temp sensor and the roll it plays in the GM engine management system.

Jay

thanks a lot jay
I need to correct myself. The PCM uses the coolent temp at all times, not just when cold, to calculate the proper air/fuel mixture and idle. It also uses feedback from other sensors to help calculate the mixture as well. But it plays a roll in that.

Jay
karfreek is offline   Reply With Quote
Old 08-24-2004, 12:08 PM   #10
Senior Member
True Car Nut
 
Join Date: Jan 2004
Location: Chicago,IL MWBF '04 SURVIVOR MWBF '05 SURVIVOR Napa Manager
Posts: 3,955
Thanks: 0
Thanked 0 Times in 0 Posts
Kennginn is on a distinguished road
Default

Quote:
Originally Posted by karfreek
Quote:
Originally Posted by Kennginn
Quote:
Originally Posted by karfreek
It would if it was cold. It uses the temp sensor to adjust the idle and mixture when the car is cold. A car starting cold, (Ex; sat overnight) needs a high idle and rich fuel mixture to run for the first few minutes until it starts to warm. Kinda like starting a lawn mower or snow blower. Basicly, if the the sensor is telling the car that it is warm, when it isnt iIts like trying to start a carbed car without the choke set, it may start, but not run right until warm.

Bad coolent sensors can also cause driveability and performance problems. They only cost $8 @ NAPA, so it is not a ton of $$$ lost if it isnt the problem.

When my Trans Am had a bad coolent temp sensor, it would start, then drop the RPM, to 600, then surge back to 1,200, then down to 600, then back. Also it would bog down until it was warm when trying to accelerate. Now that it is fixed it starts and goes to 1,200 until warm and then cuts to 500-600.

There is a VERY GOOD article in the newest GMHTP, (silver Z28 on the cover) it covers the GM Coolent temp sensor and the roll it plays in the GM engine management system.

Jay

thanks a lot jay
I need to correct myself. The PCM uses the coolent temp at all times, not just when cold, to calculate the proper air/fuel mixture and idle. It also uses feedback from other sensors to help calculate the mixture as well. But it plays a roll in that.

Jay
also what jay wrote the coolant temp sensor is highly cheap at NAPA come on now u know u wanna come we keep america running
Kennginn is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Lumina stalls restarts after sitting BNelson Chevrolet 6 09-24-2013 04:22 PM
91 Buick Regal Stalls when Starting Soft Ride Buick 2 12-22-2012 10:33 PM
Engine Stalls, Surges and Stumbles after Engine Wash marquette97 1992-1999 5 04-10-2008 01:43 PM
95 SE erratic idle, hard starting, stalls, no Check engine rockken_cosworth 1992-1999 14 08-22-2007 10:57 AM
Car almost stalls on right hand turns,TSB Fuel Pump Strainer Dutch2005 1992-1999 8 06-02-2005 04:46 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 05:39 AM.


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.