Cheryl Carter

This regards our '93 SC GTS; Joe Dyer's previous car. We would appreciate your ideas on what the problem might be. We will report the symptoms and not color your opinion with what we think is going on. Neither of us are mechanically inclined so we're probably wrong anyway!

Coming back from a 4 hour trip with lots of hard acceleration and 100+ runs, we pulled up to a stop sign and the car died. In the last few minutes before the stop sign we heard a very low pitch whirring/growling noise from the rear of the car. It was barely audible but definitely a new sound.

At the stop sign I repeatedly tried starting the car; it would start and immediately die. Then I started pumping the gas pedal the moment it started and I could keep it running but very rough. It would die as soon as I put in drive so I put it in neutral revved the engine a little higher and slipped it into drive. It ran very rough the rest of the way home (3 miles, thank goodness we were almost home and not in the middle of the King Ranch!) During the last three miles if we slowed down to turn ( 5-10 mph) the car would die again. Same process as before to restart.

After arriving home we put it in the garage and tried to restart. Unless I gave it gas it would die immediately. The moment it died it always made a high piched squal from the rear of the car lasting about 2 seconds. I had Randy get under the car and he could tell the squal was coming from under the car between the rear driver's wheel and the bumper. He could also hear a soft whirring sound from the same area whenever I turned the switch to the first click. The picture shows the area the whirr and whine seem loudest.

Thanks in advance for any of your insights on the problem.

jayc67

Are you certain of the origin of the sound? Sounds like fuel pump from the description. The area in your photo is the battery box.

Your car has 2 fuel pumps I believe, one internal one external. Unless that was changed at the SC install that is.

Odds are that the short hose connecting the 2 pumps has rotted and clogged a pump.

So, no fuel pressure or low fuel pressure, and the whining is the pump digesting pieces of hose, or dying.

That's where I'd start checking anyway, since it's a fairly well known and documented problem.

That's my guess anyway, probably be wrong. I usually am

Cheryl Carter

Thanks, Jay. Are you a year round Mansfield resident? We drove right by you on this trip and Randy makes it to the Valley quite often. That's a sharp looking car on your avatar.

Leon Speed

Sounds like bad fuel delivery, maybe a bad fuel pump. I believe the location you are referring to is home to the PSD-pump.

blau928

Fuel pump/s, or in tank filter....

Giovanni

I think the car has a custom fuel pressure guage, what does it read at idle?

Cheryl Carter

It did but none of them worked and I wanted the console stock so we removed all the custom guages. Thanks.

ROG100

You need a new fuel pump by the sound of it and as already said.
What does the paperwork say about the fuel pump? Is it a 44??
Give me a call and I will talk the silly old basta** through how to check what it is.

dprantl

You can remove the fuel pump and reverse the connections to try running it backwards. Sometimes it will spit out the crap that it ingested from the in-tank pump's rubber connecting hose and will be fine. You can then use the old external but really should replace the in-tank pump with a strainer to avoid the same thing happening again.

Dan
'91 928GT S/C 475hp/460lb.ft

pcar928fan

The area just behind the drivers wheel would be the PSD, but I doubt that is the problem as I don't think that would cause the car to die... Fuel pump does sound logical...

ROG100

IIRC the car has a 44 pump wired differently through a relay maybe.

Cheryl Carter

Spoken like a true merchant banker you daft old bar steward.

Thanks all, I greatly appreciate your help. Randy thought it was the fuel pump but I know his mechanical abilities well enough to want some reassurance before he violates my car. At least he has other redeeming virtues.

Tom. M

Don't forget that the GTS's have a pump in the transmission (both manual and automatic) that pump trans fluid up to the cooler and back. I heard one of those a number of years ago that was really noisy. Not likely related to the bad running condition, but might be the noise you are hearing.

Jim M.

I vote for the fuel pump and/or fuel filter. Mine just did the same thing, reversing the polarity on the electrical connections freed up the jambed main pump, but the internal pump was DOA. Also the connecting hose had failed (2nd pic). Replaced them both as a safety precaution. I also opened up the fuel filter to find the filtering media almost completly black. (1st pic)

Jim M.

I vote for the fuel pump and/or fuel filter. Mine just did the same thing, reversing the polarity on the electrical connections freed up the jambed main pump, but the internal pump was DOA. Also the connecting hose had failed (2nd pic). Replaced them both as a safety precaution. I also opened up the fuel filter to find the filtering media almost completly black. (1st pic)

Lets try this again with pics.