LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

Car misses at low rpms when warm?

Thread Tools
 
Search this Thread
 
Old 06-18-2009, 01:49 PM
  #1  
Registered User
Thread Starter
 
cyteone's Avatar
 
Join Date: May 2008
Posts: 146
Car misses at low rpms when warm?

1994 LT1 it runs great when cold, then when it warms up it starts to stumble at low rpms(below 2500).
It almost feels like its missing at an idle. If I slam the throttle it works great (stumbles a little from the bottom then smooths out).

Anyone know what would cause misses at low rpms when warm?
The Opti, coil, and spark plugs are new.
cyteone is offline  
Old 06-18-2009, 05:13 PM
  #2  
Registered User
 
JooneJune's Avatar
 
Join Date: Aug 2006
Posts: 719
You throwing any codes? (SES light on?)
JooneJune is offline  
Old 06-19-2009, 12:19 PM
  #3  
Registered User
Thread Starter
 
cyteone's Avatar
 
Join Date: May 2008
Posts: 146
The check engine light is not on, and I know it works.

The car runs rich at low rpms when warm or cold, but when its cold it feels like it runs great, it only starts to stutter when warm.

I can smell the unburned hydrocarbons from the exhaust...
cyteone is offline  
Old 06-21-2009, 04:22 PM
  #4  
Registered User
 
94 Assault z28's Avatar
 
Join Date: Apr 2009
Location: Strong Island New York
Posts: 59
did you recently change your spark plugs or wires or anything along that line i had the same problem. plugs were a bit too loose. try n check.
94 Assault z28 is offline  
Old 06-22-2009, 10:45 AM
  #5  
Registered User
 
form94's Avatar
 
Join Date: May 2005
Location: Wisconsin
Posts: 141
sounds like a vaccum leak. did you check for leaks?
form94 is offline  
Old 06-24-2009, 09:45 PM
  #6  
Registered User
 
BLKOUTZ28's Avatar
 
Join Date: May 2008
Location: Dayton, Ohio
Posts: 84
Has this problem been fixed.
BLKOUTZ28 is offline  
Old 06-25-2009, 06:27 PM
  #7  
Registered User
 
tricky69's Avatar
 
Join Date: Apr 2009
Posts: 31
would like to know if anyone has an answer for this, i have the same problem with my 1994 z28. only does it when car is warm never wen its cold.
tricky69 is offline  
Old 06-26-2009, 12:03 PM
  #8  
Registered User
Thread Starter
 
cyteone's Avatar
 
Join Date: May 2008
Posts: 146
I did check for vacuum, it was at 16 in.hg and nice and steady, so no vacuum leak...

I pulled the plugs and they still look new after about 300 miles...

I pulled off the mass air flow connecter, started the car, and let it idle. It didn't seem to make a difference except that the check engine light came on.

Does this mean my MAF is bad?

Or do I actually have to drive the car with the MAF off to see if it makes a difference?

I really wish I could figure this out...
cyteone is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
97SSdude
LT1 Based Engine Tech
9
12-31-2014 07:43 PM
AlaskaZ28
LT1 Based Engine Tech
4
12-16-2014 07:24 PM
AlaskaZ28
New Member Introduction
2
12-10-2014 02:39 PM
AlaskaZ28
LT1 Based Engine Tech
1
12-10-2014 02:37 PM
sleeperZ96BT
LT1 Based Engine Tech
300
06-05-2005 09:33 PM



Quick Reply: Car misses at low rpms when warm?



All times are GMT -5. The time now is 06:05 PM.