tazman

I was going to wash my baby I got to the car wash and was waiting to go into a stall and it started to sputter like it was running out of gas then died. I tried to start it again but it would just sputter giving it gas did not help. I tried unplugging one of the injectors but that did not help the fuel pressure was at 12psi during this time and would only momentarily jump higher when I first turned the key then fall to 12. After trying to start it a couple of times pulling the DME relay out and putting it back in then disconecting the vacum line to the fuel FPR the fuel pressure droped to 0psi. I then checked the fuel pump fuse which was bad so I tried another fuse which burnt out after trying to start it again.

FYI
It would not start for me one time last year it just sputtered it was parked but facing down hill and I rolled it off the hill and it started and I didn't have any other problems until now.

I didn't check anything yet so I would like some opinions what you think is wrong. I am not sure when the fuel filter was last changed. Could that be blocked to the point it would cause the pump to blow the fuse?
If the FPR would go the pressure would just be too high rigth?

What I was thinking of doing for my test was undo the fuel filter and turn the key on and I should get fuel out of the pump right?

I am suppose to use special wrenches on the fuel lines right? Flared?(can't remember what they are called) What sizes do I need? My Haynes manual is at my garage (I hope lol) is it hard to replace the fuel pump on an 88 951S?

I plan to make mods to my car for more HP if I need a new pump should I be getting one that can flow more? If so which one and where to get it would help me alot (I have bought most of my stuff from Paragon so far)

Oh also is there a place for a tow hook for my car that would make it easier to get it up on a flat bed?

All coments and suggestions are welcome!
TIA

2zeroes

tazzmann:
[quote] Oh also is there a place for a tow hook for my car that would make it easier to get it up on a flat bed? <hr></blockquote>

On your front bumper, in the middle of the intercooler slot, is a black plastic cover. If you pull the cover out, you'll see the place to screw in your tow eye. You should have a tow eye in your tool kit, but I've heard not everyone has one. If you don't, you should get one at the dealership. Let me know if you need the part number, I can look it up.

Melchior

There are two things that I can think of off-hand. The DME relay my need to be replaced due to some kind of short. It is about the same price from a Porsche dealer as you could buy it from anywhere esle ($30~). If you have the old style (ie it says 944 in the part number instead of 968) then you should probably replace it anyway since it WILL fail eventually. The new/improved one is taller in order to allow for better heat distribution. The other problem that you might have is not the fuel pump itself, but the check valve that is attached to the output side of the pump. It costs about $12~ to replace but requires pulling the pump out to do so. Yes, you must use flared wrenches to remove the fuel lines or you WILL strip the nuts. The check valve gets corroded and ends up clogging the line; preventing fuel flow. As a word or caution, before you attempt to remove the check valve using a flared wrench from the pump, you must apply a lot of rust penetrating fluid (like Liquid Wrench) and allow it plenty of time to work on the corrosion or you will end up stripping the bolt. Have fun! <img src="graemlins/c.gif" border="0" alt="[ouch]" />

tazman

Thanks 2zeroes I will check in the hatch to see if I have the tow hook. I will probably just get it from Paragon if I don't have it.

I am going to the garage to check it out now I read somewhere that I need 17 & 19mm wrenches so I will pick them up first. Thanks for the heads up on the check valve David I will disconect that and check the pump.

tazman

I removed the filter and the pump but none of that is my problem or is not my only problem. When I disconect the electrical conection back at the fuel pump and jump the DME relay pin 30 to 87b when I put a fuse in for the fuel pump it sparks and blows right away.

Does the wire go straight from the fuse to the pump?

Anybody know which route the wire takes from the fuse block to the pump?

I wish it was just replacing the pump <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" /> which still might be bad and caused the wire to melt or something.

2zeroes

Tom:

You didn't mention this in any of your posts, but do you hear the fuel pump when you turn the key to the number 2 position?

tazman

No the pump wasn't running at all 2zeroes.

Well the pump did work but I just ordered another one so that I don't have to pull everything apart again later. Allthough I don't know how I would be able to do the fuel filter without pulling the pump apart from the gas tank with that tranny cooler there it's so tight. I have to trace the wire to try to find where its shorted out yet which seems impossible while I'm laying on my back under the car.