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

Start-up Problems...

Thread Tools
 
Search this Thread
 
Old May 2, 2009 | 08:42 PM
  #1  
latindragons's Avatar
Thread Starter
Launching!
 
Joined: Jul 2007
Posts: 267
Likes: 1
From: Fishers, IN
Default Start-up Problems...

Ok, I searched and found a thread that this may be fuel pressure related but thought I'd ask for my specific case.

I have a 1995 Trans Am and I've been having problems with the start-up lately. Basically, after the car's been sitting for a while I'll go to turn it on and it'll crank for awhile before turning on (varies from ~3 seconds to as long as ~30 seconds).

After it starts (finally) it may die immediately or drop in RPM then go back to normal. Then I'll have to let it sit a bit before moving because when I give it throttle, it'll sputter and try to die. After a few minutes, it'll be perfectly normal. Can go WOT, blip the throttle, drive, anything and it'll be fine. It's just the initial start-up.

Sorry for the long post, but I wanted to give anyone as many of the symptoms as possible. I've changed the plugs and just did the cap and rotor (hoping it's not the opti just yet). And changed out the fuel pump maybe a year ago.

Any suggestions are welcome. Thanks is advance guys!
Reply
Old May 2, 2009 | 10:12 PM
  #2  
MTBSully's Avatar
TECH Fanatic
15 Year Member
Photogenic
Photoriffic
Liked
iTrader: (7)
 
Joined: Feb 2008
Posts: 1,265
Likes: 18
From: Bolton Masshole
Default

only way to tell is to get a fuel pressure gauge which can be had for around $35 at autozone. A very good investment if you ask me. I was having the EXACT same problem as you with my car. I went out and bought the fuel pressure guage, and found that i had zero fuel pressure after priming, and around 20psi while idling, which is obviously very low.
Reply
Old May 2, 2009 | 10:57 PM
  #3  
latindragons's Avatar
Thread Starter
Launching!
 
Joined: Jul 2007
Posts: 267
Likes: 1
From: Fishers, IN
Default

That's what I was thinking, too. Just wanted to hear it from other guys. I'll go ahead and pick one up and try it.
So....this is going to be stupid, but I'm used to carburated cars, how would you use the gauge? And what reading should I be looking for? Sorry if I sound stupid haha. But we all started off ignorant so have pity haha
Reply
Old May 3, 2009 | 12:24 AM
  #4  
killagt's Avatar
TECH Fanatic
iTrader: (3)
 
Joined: Dec 2007
Posts: 1,737
Likes: 2
Default

Originally Posted by MTBSully
only way to tell is to get a fuel pressure gauge which can be had for around $35 at autozone. A very good investment if you ask me. I was having the EXACT same problem as you with my car. I went out and bought the fuel pressure guage, and found that i had zero fuel pressure after priming, and around 20psi while idling, which is obviously very low.
my fuel pressure jump to 47-50 psi after priming, its normal ?
Reply
Old May 3, 2009 | 12:48 AM
  #5  
trippinholyman's Avatar
Launching!
 
Joined: Feb 2009
Posts: 280
Likes: 0
From: bodymore
Default

Originally Posted by latindragons
That's what I was thinking, too. Just wanted to hear it from other guys. I'll go ahead and pick one up and try it.
So....this is going to be stupid, but I'm used to carburated cars, how would you use the gauge? And what reading should I be looking for? Sorry if I sound stupid haha. But we all started off ignorant so have pity haha
on the back of the intake manifold, the back part of the fuel rail on the driver side i think, there is a schrader valve. just get a normal valve stem removal tool (IMPORTANT! MAKE SURE YOU RELIEVE FUEL PRESSURE BY REMOVING GAS CAP AND PUSHING SCHRADER VALVE IN!!!!!!!!!) and remove the schrader valve from the fuel rail (this is the test port). plug the gauge in there make sure its sealed and all. prime the system, see what the pressure is.

for lt1 cars, normal primed is 41-47. normal idle is anywhere from 3-10 psi less than that.

if its low, check for a clogged fuel filter, clogs in the lines or bends anywhere (like when you kink a hose).

worst case scenario you might need a new fuel pump. make sure you cut the trap door though that way itll be easier in the future! http://www.taekwondoplus.org/z28/fuelpump.html

http://shbox.com/1/fp_reg.jpg

thats a pic of the fuel pressure regulator / schrader valve

check your reg too its quick and easy
Reply
Old May 3, 2009 | 12:19 PM
  #6  
latindragons's Avatar
Thread Starter
Launching!
 
Joined: Jul 2007
Posts: 267
Likes: 1
From: Fishers, IN
Default

Thanks a lot Trippin and MTB!! That's exactly what I needed. I'll try that out and see if it works.
Reply
Old May 3, 2009 | 01:23 PM
  #7  
MTBSully's Avatar
TECH Fanatic
15 Year Member
Photogenic
Photoriffic
Liked
iTrader: (7)
 
Joined: Feb 2008
Posts: 1,265
Likes: 18
From: Bolton Masshole
Default

let us know how it goes!
Reply




All times are GMT -5. The time now is 12:44 PM.

story-0
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-1
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-2
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-3
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-4
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-5
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-6
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-7
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE
story-8
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

The world was a better place when it was still around.

By Brett Foote | 2026-01-23 09:20:37


VIEW MORE
story-9
10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever

Slideshow: The 7.0-liter LS7 was designed for absolute cutting-edge performance.

By Verdad Gallardo | 2026-01-07 18:36:00


VIEW MORE