TPI LB9 Needs gas pedal pumped to start... HELP
#1
Junior Member
Thread Starter
Join Date: Jan 2013
Location: Nebraska
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1986 G92 Z-28
Engine: '89 L98 (5.7 TPI)
Transmission: 700r4
Axle/Gears: 3.23
TPI LB9 Needs gas pedal pumped to start... HELP
Hey fellas, I tried to get an answer to this question last summer, and got no help so Im trying again. My 86z with the lb9 wont start without me pumping the pedal. The car will start without it, but it takes 8-10 secs on cranking, then sort of sputters to a start. If i give it gas when cranking she fires right up, but i have to pump one to two more times otherwise she idles soo low that shell die again. Once shes started though, no dying or idling issues. I just have to pump her to get her to fire. I put in a new fuel pump, hypertech eprom, and ecu. Those are the only mods i can thnk of that ive installed that may affect fuel delivery. Anyone ever had/heard of this issue? And does anyone have any fixes?
#3
Junior Member
Thread Starter
Join Date: Jan 2013
Location: Nebraska
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1986 G92 Z-28
Engine: '89 L98 (5.7 TPI)
Transmission: 700r4
Axle/Gears: 3.23
Re: TPI LB9 Needs gas pedal pumped to start... HELP
Whats the bleed down rate? And how can i check the fuel pressure w/o a fuel pressure gauge?
#4
Re: TPI LB9 Needs gas pedal pumped to start... HELP
You need a gauge, bleed down rate is when you shut the key off. It should maintain fuel pressure for a long while. If it drops to zero then there's something wrong, that might be why it cranks so long before starting. The pump has to refill the whole system & work the air out.
#5
Supreme Member
iTrader: (13)
Join Date: Apr 2005
Location: Not in Kansas anymore
Posts: 7,733
Likes: 0
Received 11 Likes
on
11 Posts
Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Re: TPI LB9 Needs gas pedal pumped to start... HELP
There is no accelerator pump on a injection engine like on a carby
#6
Supreme Member
iTrader: (8)
Join Date: Oct 2001
Location: Il
Posts: 11,734
Received 795 Likes
on
528 Posts
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: TPI LB9 Needs gas pedal pumped to start... HELP
I read in the service manual or owners manual, If you hold the pedal 1/3 of the way down or less while cranking, it gives it a lil extra fuel.
Now if you hold it to the floor, it goes into clear flood mode.
IIRC
I'd check out the cold start inj circuit if you haven't.
Now if you hold it to the floor, it goes into clear flood mode.
IIRC
I'd check out the cold start inj circuit if you haven't.
#7
Junior Member
Thread Starter
Join Date: Jan 2013
Location: Nebraska
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1986 G92 Z-28
Engine: '89 L98 (5.7 TPI)
Transmission: 700r4
Axle/Gears: 3.23
Re: TPI LB9 Needs gas pedal pumped to start... HELP
Thanks for the reply guys. I had her towed this morning, she would mot start whatsoever and eventually stopped cranking. 8 hours on a charger and it still wont even crank on a month old battery.
Thread
Thread Starter
Forum
Replies
Last Post
1992 Trans Am
History / Originality
27
05-10-2023 07:19 PM
Sanjay
Engine/Drivetrain/Suspension Parts for Sale
1
08-12-2015 03:41 PM