ok i've had a issue recently with losing fuel pressure over extended periods of time. i had always thought it was something to do with my fuel pump. But tonight i was running to get gas and decided to go to get some oil, so i drove down the road maybe 3 miles and my car started having a rough acceleration from about 1-2k rpms. so i didnt think much of it first then when i was driving back my SES light started flashing at me, I could feel missing hard, i stopped checked all my wires and they were all on tight. what do you guys think?

 

I think you need to read the codes.

 

Def scan the codes. If not, when was the last time you had a decent tune up?

 

Flashing light means misfire(s). Pull the codes so you'll know which direction to start looking.

 

Have you checked the fuel pressure under load? Under what conditions is it "losing fuel pressure over extended periods of time." Do you mean the pressure bleeds off over a period of time when you shut the engine down? Or do you mean under extended heavy load the fuel pressure drops?

 

well i'm going to try and get a code reader today and i'll throw you some codes, and i havent had a fuel pressure guage check yet, but it does bleed off when the engine is off, for extended amounts of time.

 

Ok, sorry for the late update, i havent had it code read yet i am going to get it read tomorrow but i did hook it up to a fuel pressure guage, i was getting 40psi all around the board, on and underload. if this helps you guys i wanna thank ya guys for taking time out to help me.

 

What is the pressure a idle with the vacuum line off the regulator? And if you can hook up the tester then tape it to your windshield. Go wot the pressure should not drop below 41psi at wot.

 

that was at idle too, it pretty much stayed there maybe dropped to 37 after about 3k rpms, but i'm leaning now on doing a fuel filter first seeing if that is a possible solution

 

it could potentially be numerous things. you really need to scan the car.

 

He is 100% correct. If it does turn out to be the pump, I would do the access door mod. It can not be seen after the job is done and it is a lot less work.

 

[QUOTE= If it does turn out to be the pump, I would do the access door mod. It can not be seen after the job is done and it is a lot less work.[/QUOTE]

Def go with the access door because i put a fuel pump in my 1996 Z28 by taking the whole tank out a i regret that. I will save lots of time and hassle.

 

sorry for lack of an update, but the problem of the miss was a number 7 fuel injector. But it still has the hard start after cold, i changed the fuel filter and that fixed nothing. and it's still getting the same fuel pressure, i'm not sure if its a fuel leak, a fuel pump, or the pressure reg. any suggestions on how to test what it may be would be great. I know that it's almost impossible to diagnose on the internet so im just looking for some help. thanks i appreciate it alot.

 

What happens to the fuel pressure when you turn the engine off? You said the pressure drops off. How fast does it drop?

When it finally starts, after extended cranking, how does it run for the first few seconds?

 

i didnt really get to measure the drop off rate with the fuel pressure guage but its relatively quick i'd say 45mins of being turned off is when it will have the hard time starting.

as for how it runs it has a i high idle for maybe 1-2 seconds then just fine. i'd say it starts up then goes up to 1.5 to 1.7k rpms, then comes back down.

i don't know if this will help you out but while its driving when u push in the clutch it doesn't immediately go to idle when coming to a stop it sits at about 1500 rpms then when u come to a complete stop it goes to 1k idle.