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!

Car dies when cold

Thread Tools
 
Search this Thread
 
Old 02-08-2017, 04:33 PM
  #1  
Junior Member
Thread Starter
 
Horizontalkev's Avatar
 
Join Date: Feb 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Car dies when cold

1990 Trans am GTA tpi. When cold, the car starts up just fine but when I put it in reverse or drive it'll want to die, unless I'm holding the gas... If it does die, it takes 10 seconds for it to start back up. Will also hesitate when pressing gas.

When warm, the car runs fine with the occasional hesitation. Gas mileage is terrible though (16mpg on highway). No CEL. What should I start looking at? I'm new to these cars. Thanks
Old 02-08-2017, 05:18 PM
  #2  
Supreme Member

 
paulo57509's Avatar
 
Join Date: Jan 2000
Location: Tracy, CA
Posts: 3,178
Received 44 Likes on 38 Posts
Car: '87 IROC
Engine: LB9
Transmission: TH700R4
Re: Car dies when cold

Is your car stock or has it been modified in any way?
Old 02-08-2017, 05:36 PM
  #3  
Senior Member

iTrader: (1)
 
tavert91's Avatar
 
Join Date: Jan 2008
Location: Destin, Florida
Posts: 618
Likes: 0
Received 10 Likes on 10 Posts
Car: 91 Trans Am Convertible
Engine: LB9 5.0 TPI
Transmission: 5 SPD
Axle/Gears: Posi Rear
Re: Car dies when cold

Possibly an EGR problem.
Old 02-08-2017, 06:58 PM
  #4  
Junior Member
Thread Starter
 
Horizontalkev's Avatar
 
Join Date: Feb 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Re: Car dies when cold

Only mod is a "CAI". & the EGR was removed and blocked off
Old 02-08-2017, 08:21 PM
  #5  
Sponsor

iTrader: (92)
 
Tuned Performance's Avatar
 
Join Date: Dec 2004
Location: Mile High Country !!!
Posts: 15,393
Received 644 Likes on 569 Posts
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Car dies when cold

Do your injectors look like this ?

Old 02-10-2017, 11:23 AM
  #6  
Junior Member
Thread Starter
 
Horizontalkev's Avatar
 
Join Date: Feb 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Re: Car dies when cold

Originally Posted by Tuned Performance
Do your injectors look like this ?

I believe so, I'll check tonight when I'm back home
Old 02-23-2017, 02:45 PM
  #7  
Junior Member
Thread Starter
 
Horizontalkev's Avatar
 
Join Date: Feb 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Re: Car dies when cold

Looks like I have 3 different style injectors.. none of which look like the injector you posted about.




3 of them look like this



Only one like this



4 of them look like this
Old 02-23-2017, 04:54 PM
  #8  
Sponsor

iTrader: (92)
 
Tuned Performance's Avatar
 
Join Date: Dec 2004
Location: Mile High Country !!!
Posts: 15,393
Received 644 Likes on 569 Posts
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Car dies when cold

The multecs are problematic. For starter you might want to get a set from Southbayfuelinjectors.
Old 02-23-2017, 08:51 PM
  #9  
Junior Member
Thread Starter
 
Horizontalkev's Avatar
 
Join Date: Feb 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Re: Car dies when cold

Okay deal. Any idea why the previous owner would have 3 different injectors? And are these 22lbs or 19lbs injectors?
Old 02-23-2017, 09:54 PM
  #10  
Senior Member
iTrader: (1)
 
Galaxie500XL's Avatar
 
Join Date: Sep 2015
Location: Knoxville, TN
Posts: 679
Received 15 Likes on 14 Posts
Car: 1988 IROC-Z
Engine: 350 TPI
Transmission: T56 swap ongoing
Axle/Gears: 2.77 9-bolt Posi
Re: Car dies when cold

Most likely, 3 different repair efforts over the years.

Before getting too far into taking things apart, I'd check the coolant temperature sensor using a scan tool. I like to check them before the car is first started in the mornings...should read close to the actual air temperature.
Old 02-23-2017, 09:58 PM
  #11  
Sponsor

iTrader: (92)
 
Tuned Performance's Avatar
 
Join Date: Dec 2004
Location: Mile High Country !!!
Posts: 15,393
Received 644 Likes on 569 Posts
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Car dies when cold

Originally Posted by Horizontalkev
Okay deal. Any idea why the previous owner would have 3 different injectors? And are these 22lbs or 19lbs injectors?
305 uses 19#hr, 350 is 22#hr.
If you do dig in you might want to also replace your regulator diaphragm for good measure. Who knows it's age.
Old 02-28-2017, 12:49 PM
  #12  
Junior Member
Thread Starter
 
Horizontalkev's Avatar
 
Join Date: Feb 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Re: Car dies when cold

Where can I find an obd1 scantool that gives live data like that?

And I'm assuming I have the 22 an hour injectors? The guy I bought the car from *thinks* it's a 350. Never verified
Old 02-28-2017, 01:08 PM
  #13  
Sponsor

iTrader: (92)
 
Tuned Performance's Avatar
 
Join Date: Dec 2004
Location: Mile High Country !!!
Posts: 15,393
Received 644 Likes on 569 Posts
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Car dies when cold

You can find old otc pathfinders on eBay , or check the cts with a vom .





All times are GMT -5. The time now is 04:18 AM.