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!

88 305 tbi will not stay running

Thread Tools
 
Search this Thread
 
Old 07-28-2015, 05:06 PM
  #1  
Junior Member
Thread Starter
 
J-YO-88's Avatar
 
Join Date: Feb 2015
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
88 305 tbi will not stay running

So everything was fine and now it will not stay running for more than a minute , whether in gear or not. I can hold throttle open to steady 2000 rpm and it will just drop out. I have replaced iat sensor , cap and rotor, coil , fuel pump relay and harness. Plenty of fuel appears to be dumping in tbi , it will just stop about 45 seconds after running.
What is next?
Old 07-28-2015, 05:19 PM
  #2  
Supreme Member

iTrader: (14)
 
aliceempire's Avatar
 
Join Date: Nov 2008
Location: Milwaukee
Posts: 1,996
Received 140 Likes on 116 Posts
Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: 88 305 tbi will not stay running

When it fails again, check if you lost fuel or spark. My guess it will be spark, then it nery well could be your ign. module.
Old 07-28-2015, 06:34 PM
  #3  
Junior Member
Thread Starter
 
J-YO-88's Avatar
 
Join Date: Feb 2015
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Re: 88 305 tbi will not stay running

I think your on to something. I pulled the cap again and pulled the module it it was pretty corroded. The two wires- green and white that connect - plastic plug disintegrated . I picked up a new module , but need to figure out a repair on the plug.
Thank you for the advice
Old 07-29-2015, 05:57 PM
  #4  
Junior Member
Thread Starter
 
J-YO-88's Avatar
 
Join Date: Feb 2015
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Re: 88 305 tbi will not stay running

So ignition module is changed. Now it is idling pretty rough, and seems to be rich . Fuel actually misting out the top of the tbi.
Any ideas?
Old 07-29-2015, 07:04 PM
  #5  
Member
 
Queball's Avatar
 
Join Date: May 2015
Location: Prescott Valley, Az
Posts: 113
Likes: 0
Received 0 Likes on 0 Posts
Car: 92 Camaro RS
Engine: 5.0
Transmission: 700r
Re: 88 305 tbi will not stay running

how long did u let it run after the change?....you prolly have to much fuel in the intake..(flooded sorta speak) give it time to burn it out..for bit..

check your plug wires..make sure you got the correct firing order..1 plug off gonna run like sheet!!!!!
Old 08-09-2015, 09:29 AM
  #6  
Junior Member
Thread Starter
 
J-YO-88's Avatar
 
Join Date: Feb 2015
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Re: 88 305 tbi will not stay running

So now I have determined I am losing 12 volts to fuel pump and losing the 5 volts to throttle position sensor.
Is it the computer?
Old 08-09-2015, 10:08 AM
  #7  
Supreme Member

iTrader: (1)
 
sofakingdom's Avatar
 
Join Date: Sep 2005
Posts: 26,051
Received 1,672 Likes on 1,269 Posts
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: 88 305 tbi will not stay running

Fuel actually misting out the top of the tbi
Usually this is caused by reversion in the intake (combustion pressure going backwards) which in turn is usually caused by a valve problem.

No neither of those things "is the computer". More likely, a bad connection somewhere. If your car has the in-line fuse thing off the battery (can't recall offhand which ones are wired that way) then that's where I'd start looking.
Old 08-09-2015, 10:16 AM
  #8  
Supreme Member

iTrader: (14)
 
aliceempire's Avatar
 
Join Date: Nov 2008
Location: Milwaukee
Posts: 1,996
Received 140 Likes on 116 Posts
Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: 88 305 tbi will not stay running

Originally Posted by sofakingdom

More likely, a bad connection somewhere. If your car has the in-line fuse thing off the battery (can't recall offhand which ones are wired that way) then that's where I'd start looking.
That's my thought too. Here's your wiring diagrams
http://austinthirdgen.org/mkportal/m...ine_wiring.gif
http://austinthirdgen.org/mkportal/m..._continued.gif
http://austinthirdgen.org/mkportal/m...ody_wiring.gif
Old 08-09-2015, 11:01 AM
  #9  
Junior Member
Thread Starter
 
J-YO-88's Avatar
 
Join Date: Feb 2015
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Re: 88 305 tbi will not stay running

Thank you , I will start looking deeper.
Thank you for the diagrams
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
pimp2303
TBI
7
07-27-2017 02:03 PM
apo_bailon15
TBI
4
03-28-2016 05:20 AM
Jae992
TBI
3
08-27-2015 09:07 AM
92purpz28
TBI
2
08-11-2015 02:30 PM



Quick Reply: 88 305 tbi will not stay running



All times are GMT -5. The time now is 07:04 PM.