Gottahavels1

my dad took my T/A to someone to check my fuel pressure at the rail which was down to 25 psi when the motor revvs. It takes two turns of the key to start and drives like ****. I've replaced the fuel filter and pump and i'm looking for other things to rule out. A tech at the dealership said that my car doesn't have a FPR, but has a fuel pressure sensor in or around the pump assembly. the guy said that if it went bad, i could be getting low fuel pressure. Does anyone know anything about this?

Nasty N8

iTrader: (33)

Your tech is an idiot. Your car does have a fuel pressure regulator. It is part of the fuel pump bucket. Unfortunately you can not buy it separately it comes with the assembly.

Nate

69LT1Bird

iTrader: (1)

You already asked this two weeks ago or so and received the same answer. Get the new sending unit and be done with it.

Gottahavels1

if someone answered my question i wouldn't have asked again.

Gottahavels1

what is a sending unit?

69LT1Bird

iTrader: (1)

You need this whole part to get the regulator for your car. Verifu the part number for your car, I think this is yours but it up to you to make sure. If you already put in a pump and filter time for this.

Gottahavels1

I hope i don't have to buy the whole assemby just to get a FPR. that would mean i'd have to sell my old (new) walbro pump. I heard that the assembly costs like $700...

Nasty N8

iTrader: (33)

The assembly is like $300 complete. You need to buy the entire thing to get the part you need.

And you did ask the same question already and I answered. https://ls1tech.com/forums/fueling-injection/991675-i-need-your-advice-my-fuel-problem.html

Nate

Gottahavels1

sorry i've got so many threads on this and forgot to check them all. hopefully i don't need a FPR. I'm just gonna drop the tank again and do the bucket mod and replaced my kinked lines. hopefully that will do it. I've also heard that a bad MAF can cause this... how can i tell if its bad? should the car drive different with the MAF disconnected?

69LT1Bird

iTrader: (1)

This is why people don't like to answer questions. First trying to diagnose a problem on the internet is always fun anyways.

What kinked lines? Why would you leave them kinked and then ask more questions about fixing your fuel pressure problem. It is probably not the going to fix it, you would have a volume issue more than a pressure issue.

You can unplug the MAF and it will go to the VE tables for fueling, so yes, you can unplug the MAF and try it.

After that, go buy the part so when you have the tank out your can replace the pressure regualtor.

or find a competent technician in your area and have them fix the car.

Sorry to be harsh, but when people take the time to answer your questions thoroughly and you still don't want to believe them it gets old. If you ask for advise and several people give the same answer, you can be pretty sure we are not conspiring to lead you down the wrong path.

99ssleeper

iTrader: (98)

i just bought a new gm sender on ebay for 85 shipped. just look around.

Gottahavels1

I've asked this many times because i'm trying to get as many ideas as possible. my car has had a fuel problem for over a year and i'm desperately trying to figure things out. I'm away at school... not with the car and i'm just researching for when i go home. I know that the plastic lines are slightly bent coming from the tank... i don't think it's causing everything but i might as well replace them. I don't know anyone I can trust to work on this car... so i'm not comfortable with just taking it somewhere and i don't want spend top dollar for something I can probably fix myself. Who said I don't believe anyone? I don't understand what you are getting at here.

Gottahavels1

I'm not going to just buy random parts that people recommend. For all i know you could be a dumbass or an expert. Is there anyway to determine if it is the FPR that is not performing correctly so i don't have to waste money??

69LT1Bird

iTrader: (1)

GM technician since 1984, must be a dumbass


From the service manual:
Important:: This step requires the aid of an assistant.

Relieve the fuel pressure. Refer to the Fuel Pressure Relief Procedure .
Raise the vehicle.
Disconnect the steel fuel return pipe (4) from the nylon rear return pipe (2).
Drain any remaining fuel from the fuel pipes into an approved gasoline container.
Install the J 37287 fuel pipe shut-off adapter (1) between the steel fuel return pipe and the nylon rear fuel return pipe.
Open the valve on the fuel pipe shut-off adapter.
Pressurize the fuel system using a scan tool.
Place the bleed hose of the fuel pressure gauge (6) into an approved gasoline container.
Bleed the air out of the fuel pressure gauge.
Notice: Do not allow the fuel pressure to exceed 500 kPa (72 psi). Fuel pressure in excess of 500 kPa (72 psi) may damage the fuel pressure regulator.

Slowly close the valve in the fuel pipe shut-off adapter that is connected to the fuel return pipe.
Does the fuel pressure rise above the specified value?
410 kPa (60 psi)

If no, replace fuel pressure regulator

Mr Ed

I know this is a very old thread but I want to add a couple of comments that I hope will be helpful to any who comes across this in the future (like I just did).

1. I have found the diagnostic procedure given by 69LT1Bird on several sites and it appears to be the one that, if followed, will result in the least amount of work and least money wasted on unnecessary parts.
2. The regulator IS available by itself. Here is a link to Advance Auto http://shop.advanceautoparts.com/web...RPFUELAMS_____. You might be able to find it cheaper elsewhere.
3. Unfortunately, the cheapest I have been able to find the fuel shut-off adapter is about $100 on eBay (incl. shipping). [For my own problem that I am currently trying to resolve on a 1999 Z28, this would appear to my next step. I am hoping to find someone with a shut-off adapter that I can borrow. If not, I will purchase one simply because I don't want to pull my tank and I don't want to buy a pump if it is not needed if I can possible avoid it.]