Cold Start issues - LS1TECH - Camaro and Firebird Forum Discussion

Notices
LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Cold Start issues

Reply

Old 11-07-2017, 10:36 AM
  #1  
On The Tree
Thread Starter
 
94_LT1_TransAm's Avatar
 
Join Date: Dec 2015
Posts: 133
Default Cold Start issues

So my CC503 1994 Trans Am has had this issue for a long time since the mail order tune. When the car hasn't been started over night or for a few hours the car is hard to start. When I turn the key the car fires right up but the idle is low and smells rich. Plus I have to slightly press the throttle until it can idle on its own. When its warm, like after running it to the store, it fires right up. Sometimes it will even stall if I roll to a stop light... Is this tune related or are there things I need to look into? Also while logging it the IAC is nearly pegged and trying to lower it using EEHack makes it nearly stall. No stored codes, new ac delco O2 Sensors, plugs and wires, etc... Thanks for the input!
94_LT1_TransAm is offline  
Reply With Quote
Old 11-07-2017, 11:27 AM
  #2  
Village Troll
iTrader: (2)
 
SS RRR's Avatar
 
Join Date: Oct 2002
Location: Jackstandican
Posts: 9,380
Default

Most likely tune related. Contact your tuner.
SS RRR is online now  
Reply With Quote
Old 11-07-2017, 11:36 AM
  #3  
On The Tree
Thread Starter
 
94_LT1_TransAm's Avatar
 
Join Date: Dec 2015
Posts: 133
Default

Originally Posted by SS RRR View Post
Most likely tune related. Contact your tuner.
I have, he said he can't do anything unless I have a wideband. The car runs great at the track other than that cold start issue.
94_LT1_TransAm is offline  
Reply With Quote
Old 11-07-2017, 12:00 PM
  #4  
Village Troll
iTrader: (2)
 
SS RRR's Avatar
 
Join Date: Oct 2002
Location: Jackstandican
Posts: 9,380
Default

I don't know enough about tuning to agree/disagree. However I do know those who mail order like data received. Since this happens on cold startup the car is not yet in closed loop. It could be just depending on default parameters to idle that cam and it's not jiving. Mine too will not idle when cold, but only takes a few minutes before it idles on its own.
My suggestion is to refrain from using your ehack program, gather some data, send it to your tuner and have them try and figure it out.
SS RRR is online now  
Reply With Quote
Old 11-07-2017, 12:08 PM
  #5  
TECH Veteran
 
Join Date: Apr 2008
Posts: 4,183
Default

Originally Posted by 94_LT1_TransAm View Post
Also while logging it the IAC is nearly pegged and trying to lower it using EEHack makes it nearly stall. t!
pegged...like at 160?

do the IAC counts drop drop as car warms up?

maybe your IAC valve is defective or dirty and sticking. You could remove and use some TB spray cleaner on it and the orifice it goes into. Do not pull or push on the printle when cleaning....and if someone did it is dead.
BALLSS is offline  
Reply With Quote
Old 11-07-2017, 02:26 PM
  #6  
On The Tree
Thread Starter
 
94_LT1_TransAm's Avatar
 
Join Date: Dec 2015
Posts: 133
Default

Originally Posted by ****** View Post
pegged...like at 160?

do the IAC counts drop drop as car warms up?

maybe your IAC valve is defective or dirty and sticking. You could remove and use some TB spray cleaner on it and the orifice it goes into. Do not pull or push on the printle when cleaning....and if someone did it is dead.
Yeah my IAC counts move up and down as it warms up, its just they stay near the 130 range from what I remember.
94_LT1_TransAm is offline  
Reply With Quote
Old 11-08-2017, 09:57 AM
  #7  
Village Troll
iTrader: (2)
 
SS RRR's Avatar
 
Join Date: Oct 2002
Location: Jackstandican
Posts: 9,380
Default

Stock throttle body?
SS RRR is online now  
Reply With Quote
Old 11-08-2017, 10:45 AM
  #8  
On The Tree
Thread Starter
 
94_LT1_TransAm's Avatar
 
Join Date: Dec 2015
Posts: 133
Default

Originally Posted by SS RRR View Post
Stock throttle body?
Yeah its stock, I contacted the tuner and he suggested opening the throttle blades up a little bit to get my IAC counts down. I tried lowering the IAC counts using EEHack and the car would stall out but increasing the IAC counts would increase my idle speed. I think that's my issue, the car is starving for air at idle... thoughts?
94_LT1_TransAm is offline  
Reply With Quote
Old 11-08-2017, 11:04 AM
  #9  
Village Troll
iTrader: (2)
 
SS RRR's Avatar
 
Join Date: Oct 2002
Location: Jackstandican
Posts: 9,380
Default

If you open the blades, what is your throttle position sensor doing?
SS RRR is online now  
Reply With Quote
Old 11-08-2017, 11:15 AM
  #10  
On The Tree
Thread Starter
 
94_LT1_TransAm's Avatar
 
Join Date: Dec 2015
Posts: 133
Default

Originally Posted by SS RRR View Post
If you open the blades, what is your throttle position sensor doing?
It operates normally. I know i'm gonna have to reset it after I adjust the blades to be more open.
94_LT1_TransAm is offline  
Reply With Quote
Old 11-10-2017, 12:03 PM
  #11  
On The Tree
Thread Starter
 
94_LT1_TransAm's Avatar
 
Join Date: Dec 2015
Posts: 133
Default

Alright update, adjusted my IAC down to the 15-30 range in closed loop like my tuner suggested and it fired right up this morning after sitting all night in 30 degree temps. No stalling or low rough idle! My TPS is set at .67v and smoothly rises to 4.5v according to: https://www.golenengineservice.com/d.../Adj%20TPS.pdf. It seems my car shifts sooner, is this the right voltage? I haven't drove the car that often lately so maybe i'm just thinking it shifts sooner.
94_LT1_TransAm is offline  
Reply With Quote
Old 11-10-2017, 12:28 PM
  #12  
Village Troll
iTrader: (2)
 
SS RRR's Avatar
 
Join Date: Oct 2002
Location: Jackstandican
Posts: 9,380
Default

Did you adjust the TPS for that voltage? Not completely sure, but I think once you mess with the TPS it will influence auto trans shift points.
SS RRR is online now  
Reply With Quote
Old 12-18-2017, 03:46 PM
  #13  
On The Tree
Thread Starter
 
94_LT1_TransAm's Avatar
 
Join Date: Dec 2015
Posts: 133
Default

Ok so now that the cold start low idle/rich issue has been resolved I have a new issue lol. My fuel pressure has been tested and is in spec and the car still idles great when cold, but it now only fires on the second crank. The first fire up it starts for a second or two and then dies, but then on the second fire up right after it dies [literally right after (no delay)] it fires back up like nothing happened... Idles great, no stall. Any thoughts?
94_LT1_TransAm is offline  
Reply With Quote
Old 12-21-2017, 10:33 AM
  #14  
Village Troll
iTrader: (2)
 
SS RRR's Avatar
 
Join Date: Oct 2002
Location: Jackstandican
Posts: 9,380
Default

Check your plugs.
SS RRR is online now  
Reply With Quote
Old 12-23-2017, 02:17 PM
  #15  
TECH Addict
iTrader: (3)
 
Join Date: Feb 2003
Location: Texas
Posts: 2,234
Default

Originally Posted by SS RRR View Post
Did you adjust the TPS for that voltage? Not completely sure, but I think once you mess with the TPS it will influence auto trans shift points.
Yup,it will
moehorsepower is offline  
Reply With Quote

Thread Tools
Search this Thread
Quick Reply: Cold Start issues


Archive Advertising Cookie Policy Privacy Statement Terms of Service

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: