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

Rough idle and runs rich

Thread Tools
 
Search this Thread
 
Old 01-26-2015, 02:53 PM
  #1  
Registered User
Thread Starter
 
Iamherefornow's Avatar
 
Join Date: Jan 2015
Posts: 1
Rough idle and runs rich

Hi new member. I purchased a 1994 Z about 6 months ago and have been slowly fixing little issues with it. But since I have owned it the car has had a rough idle and running rich issue. Only getting up to 12 to 14 mpg and smell of gas out tailpipe. The cat has been removed it does have an exhaust leak were the cat was removed. I am getting no codes the opti spark, plugs, wires were replaced.
Iamherefornow is offline  
Old 01-26-2015, 04:26 PM
  #2  
Registered User
 
Chimera96's Avatar
 
Join Date: Jun 2003
Posts: 1,083
Re: Rough idle and runs rich

you still have 02's?

if you have a exhaust leak pre-02's, PCM reads lean and commands more fuel which = running rich
Chimera96 is offline  
Old 01-26-2015, 04:57 PM
  #3  
Administrator
 
Injuneer's Avatar
 
Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
Posts: 70,646
Re: Rough idle and runs rich

Best thing you can do is run a data log of the PCM while operating under the conditions you describe. One of us can review the data log and look for possible causes. Could be a faulty coolant temp sensor, the misfires themselves, as mentioned above exhaust leaks before the O2 sensor (or an open exhaust near the O2 sensor), problems with EGR, faulty O2 sensor or sensor wiring, etc.

Free software download..... all you need it to but a cable. Ready-made cable preferred to do-it-yourself, since the quality of the Chines-made components is becoming a problem.

https://www.camaroz28.com/forums/com...95-lt1-874306/

And obviously, removing the cat is going to make the exhaust smell.
Injuneer is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
DirtyDaveW
Forced Induction
13
12-01-2016 05:37 PM
bfmv13trivium
General 1967-2002 F-Body Tech
9
01-14-2015 09:57 AM
1775.Z28
LT1 Based Engine Tech
7
01-11-2015 10:51 AM
AlaskaZ28
LT1 Based Engine Tech
9
01-01-2015 12:30 PM
F(ast)-body
LT1 Based Engine Tech
8
02-26-2003 09:05 AM



Quick Reply: Rough idle and runs rich



All times are GMT -5. The time now is 05:47 AM.