Search



Go Back   Third Generation F-Body Message Boards > Tech Boards > Tech / General Engine
Register Forgot Password?

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!
Sponsored by Weld Racing
Click Here

Welcome to ThirdGen.org!
Welcome to ThirdGen.org.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!


Reply
 
Thread Tools Search this Thread
Old 01-03-2008, 11:05 AM   #1
Member
 
Viking's Avatar
 
Join Date: May 2000
Location: Budd Lake NJ, USA
Posts: 199
Car: / 89 IROC /
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)

Lope at idle

hey guys, any ideas why I might have a lope at idle, and while in drive with foot on the brake? The RPM's dip like the car is going to stall, recovers, then dips again. Never stalls though.
I did a tune up on it to try and fix. Did cap/rotor, O2 Sensor, fuel filter, PCV, plugs. Still doing it.... maybe a clogged injector?
__________________
89 IROC original owner, 369,000 miles on original 305 TPI. Daily Driver for the last 25 yrs.
Viking is offline vBGarage Page   Reply With Quote
Old 01-03-2008, 11:27 AM   #2
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,111
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

Maybe. Or a cylinder with low compression - do a compression check.
five7kid is offline vBGarage Page   Reply With Quote
Old 01-03-2008, 02:47 PM   #3
Member
 
Viking's Avatar
 
Join Date: May 2000
Location: Budd Lake NJ, USA
Posts: 199
Car: / 89 IROC /
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)

Re: Lope at idle

Quote:
Originally Posted by five7kid View Post
Maybe. Or a cylinder with low compression - do a compression check.
Thanks, I will. I raised the idle setting a little bit too, to see if it solved the lope, but now the car is hard to start. Can raising the idle cause that??
Viking is offline vBGarage Page   Reply With Quote
Old 01-03-2008, 02:47 PM   #4
Moderator
 
Air_Adam's Avatar
 
Join Date: Oct 2002
Location: Saskatoon, SK, Canada
Posts: 9,067
Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
Transmission: TH350, A5
Axle/Gears: 2.73 posi, 3.06 posi

Classifieds Rating: (0)

Send a message via MSN to Air_Adam
Re: Lope at idle

Is the SES light coming on?

Have you checked all the plug wires to make sure they are all tight? Are all the plugs tight? Is a plug wire maybe burned on the exhaust manifold?

I had a problem with a dead cylinder that ran similar to what you described with my '97 LT1 a few weeks back - checked all the wires with a timing light and found #8 was not firing. Plug wire was tight on both ends, and the spark plug was tight. Took out the wire and found it rubbed through on the PS pulley (all the passnger bank wires are routed between the block and PS pump) and was grounded out. Replaced the wire and its all OK now.
----------
Quote:
Originally Posted by Viking View Post
Thanks, I will. I raised the idle setting a little bit too, to see if it solved the lope, but now the car is hard to start. Can raising the idle cause that??
How did you raise the idle on a TPI car?

Last edited by Air_Adam; 01-03-2008 at 02:47 PM. Reason: Automerged Doublepost
Air_Adam is offline vBGarage Page   Reply With Quote
Old 01-03-2008, 02:54 PM   #5
Member
 
Viking's Avatar
 
Join Date: May 2000
Location: Budd Lake NJ, USA
Posts: 199
Car: / 89 IROC /
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)

Re: Lope at idle

I hear you about the dead cylinder thing, but the car runs fine when at speed. On the highway, for example, you would never know there was a issue. Its just when stopped with foot on brake mostly in drive.
Viking is offline vBGarage Page   Reply With Quote
Old 01-04-2008, 12:41 AM   #6
Moderator
 
Air_Adam's Avatar
 
Join Date: Oct 2002
Location: Saskatoon, SK, Canada
Posts: 9,067
Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
Transmission: TH350, A5
Axle/Gears: 2.73 posi, 3.06 posi

Classifieds Rating: (0)

Send a message via MSN to Air_Adam
Re: Lope at idle

Check your IAC (idle air control) solenoid. It may be having some issues, or is maybe just dirty.
Air_Adam is offline vBGarage Page   Reply With Quote
Old 01-04-2008, 07:44 AM   #7
Supreme Member
 
Viprklr's Avatar
 
Join Date: Feb 2002
Location: N. Illinois
Posts: 3,460
Car: 92 GTA/ 00 TA
Engine: 383/350
Transmission: 700R4/T-56

Classifieds Rating: (5)

Re: Lope at idle

Quote:
Originally Posted by Air_Adam View Post

How did you raise the idle on a TPI car?
The minimum air/idle adjustment screw on the drivers side of the throttle body.
Viprklr is offline vBGarage Page   Reply With Quote
Old 01-04-2008, 08:40 AM   #8
Member
 
Viking's Avatar
 
Join Date: May 2000
Location: Budd Lake NJ, USA
Posts: 199
Car: / 89 IROC /
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)

Re: Lope at idle

Quote:
Originally Posted by Air_Adam View Post
Check your IAC (idle air control) solenoid. It may be having some issues, or is maybe just dirty.
Thanks Air Adam, I will have that check out, good idea
Viking is offline vBGarage Page   Reply With Quote
Old 01-04-2008, 11:34 AM   #9
Member
 
golden's Avatar
 
Join Date: Nov 2005
Location: Quebec
Posts: 188
Car: '89 Firebird
Engine: 305 TBI (LO3)
Transmission: 700R4
Axle/Gears: 10 bolts 2.73

Classifieds Rating: (0)
Send a message via MSN to golden
Re: Lope at idle

Well maybe its your torque converter ....
golden is offline vBGarage Page   Reply With Quote
Old 01-04-2008, 02:31 PM   #10
Moderator
 
Air_Adam's Avatar
 
Join Date: Oct 2002
Location: Saskatoon, SK, Canada
Posts: 9,067
Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
Transmission: TH350, A5
Axle/Gears: 2.73 posi, 3.06 posi

Classifieds Rating: (0)

Send a message via MSN to Air_Adam
Re: Lope at idle

Quote:
Originally Posted by golden View Post
Well maybe its your torque converter ....
I highly doubt it. When a lock-up mechanism in a converter fails, it will act just like the clutch in a manual trans car. When you come to a stop (or put it in drive) it will just stall, just like if you try to stop in a manual trans car when in gear without pushing down the clutch pedal.
Air_Adam is offline vBGarage Page   Reply With Quote
Old 01-04-2008, 03:18 PM   #11
Member
 
Viking's Avatar
 
Join Date: May 2000
Location: Budd Lake NJ, USA
Posts: 199
Car: / 89 IROC /
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)

Re: Lope at idle

yes, the T/C is fairly new. Had the tranny rebuilt not too long ago, and I know I paid for a beefier T/C in anticapation of when the original 305 finally gives up the ghost, I'd put a stronger mill in there.

I'm going to try replacing the Idle air Control, and return the idle back to normal.

Still cannot figure out why adjusting the idle might cause the car to be hard to start. Hopefully the new IAC and returning the idle back to where it belongs will solve all.
Viking is offline vBGarage Page   Reply With Quote
Old 01-04-2008, 07:58 PM   #12
Moderator
 
Air_Adam's Avatar
 
Join Date: Oct 2002
Location: Saskatoon, SK, Canada
Posts: 9,067
Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
Transmission: TH350, A5
Axle/Gears: 2.73 posi, 3.06 posi

Classifieds Rating: (0)

Send a message via MSN to Air_Adam
Re: Lope at idle

Quote:
Originally Posted by Viking View Post
yes, the T/C is fairly new. Had the tranny rebuilt not too long ago, and I know I paid for a beefier T/C in anticapation of when the original 305 finally gives up the ghost, I'd put a stronger mill in there.

I'm going to try replacing the Idle air Control, and return the idle back to normal.

Still cannot figure out why adjusting the idle might cause the car to be hard to start. Hopefully the new IAC and returning the idle back to where it belongs will solve all.
It may be harder to start because some of the 'base' settings the ECM looks for are all out of whack with that stop screw changed positions. I'm not sure if thats an issue the way the TPI cars' controls are set up (my 3rdgen has a carb, the LT1 car is an OBD2 car), but lots of imports with EFI can have issues like that.

Set the idle stop back to stock, and I would suggest removing the entire throttle body unit and cleaning it out thoroughly with Throttle Body Cleaner spray (not carb cleaner, its got too much oil in it) to get all the carbon off the throttle bores & blades, and out of the IAC passage. Clean the IAC solenoid at the same time with the cleaner spray.

My LT1 had a few odd gremlins like a sticky fast idle - would randomly get 'stuck' idling at 1200-1500 rpm after letting off the throttle - that were cured just by removing, disassembling, and cleaning the throttle body. Clean the MAF at the same time also with throttle body cleaner (you cannot use carb cleaner on the MAF due to the oil in it - that could make your problem worse).

Even if that doesn't solve the problem, it at least eliminates two possible issues, and its cheap and fairly quick job to do - cleaning the throttle body and MAF - and it can only help it run better.
Air_Adam is offline vBGarage Page   Reply With Quote
Old 01-06-2008, 11:25 AM   #13
Supreme Member
 
Supervisor42's Avatar
 
Join Date: Jul 2005
Location: Arab, Alabama
Posts: 1,667
Car: 1988 Trans Am GTA
Engine: 350 4BBL
Transmission: 700R4
Axle/Gears: 3.27

Classifieds Rating: (0)
Re: Lope at idle

Quote:
Originally Posted by Viking View Post
hey guys, any ideas why I might have a lope at idle, and while in drive with foot on the brake? The RPM's dip like the car is going to stall, recovers, then dips again. Never stalls though.
I did a tune up on it to try and fix. Did cap/rotor, O2 Sensor, fuel filter, PCV, plugs. Still doing it.... maybe a clogged injector?
Eliminate the power brake booster as a source of a vacuum leak by plugging it off and see if it makes any difference. (don't forget you won't have power brakes when you test drive it)
Supervisor42 is offline vBGarage Page   Reply With Quote
Old 01-16-2008, 11:31 AM   #14
Member
 
Viking's Avatar
 
Join Date: May 2000
Location: Budd Lake NJ, USA
Posts: 199
Car: / 89 IROC /
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)

Re: Lope at idle

Well - after 2 weeks I am still grappeling with this issue. Here is what I have done to to solve the surging at idle, with foot on brake. Also now the car is starting to surge while driving with foot lightly on gas. Seems almost like its gas is being cut back with each "surge". Car does not do this when cold, its worth saying, only when its warmed up.

I have so far:
-Replaced the idle air control
-Replaced O2 sensor
-Replaced fuel filter
-Replaced Cap and rotor
-Replaced spark plugs
-Cleaned throttle body
-Eliminated the brake booster as possible cause.

I received a reccomendation to replace the Throttle Position sensor. Please let me know if is this worthwhile, or any other suggestions. Thanks!
Viking is offline vBGarage Page   Reply With Quote
Old 01-16-2008, 12:21 PM   #15
Member
 
Join Date: Jul 2006
Location: upstate NY
Posts: 167
Car: 88 GTA
Engine: 355
Transmission: TH350
Axle/Gears: 3.42 Auburn Pro

Classifieds Rating: (0)
Re: Lope at idle

What did you find when you did the very first suggestion - the compression check?
jtrescot is offline vBGarage Page   Reply With Quote
Old 01-16-2008, 12:28 PM   #16
Member
 
Viking's Avatar
 
Join Date: May 2000
Location: Budd Lake NJ, USA
Posts: 199
Car: / 89 IROC /
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)

Re: Lope at idle

Quote:
Originally Posted by jtrescot View Post
What did you find when you did the very first suggestion - the compression check?
As far as I know, my guy did not do a compression check. I will ask why.
Viking is offline vBGarage Page   Reply With Quote
Old 01-17-2008, 01:53 PM   #17
Member
 
Viking's Avatar
 
Join Date: May 2000
Location: Budd Lake NJ, USA
Posts: 199
Car: / 89 IROC /
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)

Re: Lope at idle

Quote:
Originally Posted by Viking View Post
As far as I know, my guy did not do a compression check. I will ask why.
Yes, all cylinders were checked, all equal.
Viking is offline vBGarage Page   Reply With Quote
Old 01-17-2008, 05:50 PM   #18
Moderator
 
Air_Adam's Avatar
 
Join Date: Oct 2002
Location: Saskatoon, SK, Canada
Posts: 9,067
Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
Transmission: TH350, A5
Axle/Gears: 2.73 posi, 3.06 posi

Classifieds Rating: (0)

Send a message via MSN to Air_Adam
Re: Lope at idle

Quote:
Originally Posted by Viking View Post
Yes, all cylinders were checked, all equal.
What where the numbers?
Air_Adam is offline vBGarage Page   Reply With Quote
Old 01-31-2008, 10:30 AM   #19
Member
 
Viking's Avatar
 
Join Date: May 2000
Location: Budd Lake NJ, USA
Posts: 199
Car: / 89 IROC /
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)

Re: Lope at idle

for anyone interested, finally fixed my issue. All injectors tested low to bad. Replaced all 8 injectors.
Viking is offline vBGarage Page   Reply With Quote
Old 01-31-2008, 02:00 PM   #20
Junior Member
 
Join Date: Jan 2008
Posts: 97

Classifieds Rating: (0)
Re: Lope at idle

have an automatic 92 v6 3.1 l camaro...i just pulled it out of my drive way it started fine...as i got out of the driveway it got really shaky like it would stall....then a few seconds later it did stall..i tried to start it but it would turn over...i tried a few more times it still didnt work...i came back a few minutes later and it still didnt work.. i have 3/4 left in my gas tank ...any ideas what could wrong
ckyfreak2010 is offline vBGarage Page   Reply With Quote
Old 01-31-2008, 02:00 PM
ThirdGen
1992 Camaro




Paid Advertisement


Reply

Go Back   Third Generation F-Body Message Boards > Tech Boards > Tech / General Engine

Tags
31, 350, bad, booster, brake, car, chevy, engine, idle, lope, lopes, lot, power, started, tuneup, v6, warm
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

 


1982 Camaro '82 || 1983 Camaro '83 || 1984 Camaro '84 || 1985 Camaro '85 || 1986 Camaro '86 || 1987 Camaro '87 || 1988 Camaro '88 || 1989 Camaro '89 || 1990 Camaro '90 || 1991 Camaro '91 || 1992 Camaro '92


All times are GMT -5. The time now is 08:50 PM.


Powered by vBulletin® Version 3.7.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
All content copyright 1997 - 2014 ThirdGen.org. All rights reserved. No part of this website may be reproduced without the expressed, documented, and written consent of ThirdGen.org's Administrators.

Emails & Contact Details