jaholmes

I know it's been asked before but my fuel pump seems way too loud. You can here in from inside the car and when you are outside it's very loud. I usually let it run for about 5 seconds and it's still sometimes hard to start the car. Sometimes I have to floor / pump the gas to get it to start. Other times it fires right up.

So I thinking the pump may be on it's last leg. I have replaced the fuel filter and had the injectors flow checked and cleaned as part of while your in there maintenance. Plugs, wires, distributor...was replace too.

I really can't think of anything else that could be causing my starting problems.

So looking at Pelican parts they have a regular fuel pump and a high output for racing motorsport "044" option. Anyone use this one yet, or is everyone just running the normal pump.

Thanks,
Jim

DaveM993

Did they give an associated HP increase?

chris walrod

We use two variants of the 044 pump on our racecars but dont its necessary on a street driven 993. Just replace with standard issue.

Stealth 993

Are you sure it's the fuel pump, & not the buzzing of the hydraulic pump for the brakes?

A high flow fuel pump is a WASTE of money on a stock motor, you will get 0 benefit from it.

jaholmes

Hmm, not sure now. The fuel pump us in the passenger front fender right. Where is the hydraulic pump for the brakes. One of them seems to run for 10 seconds or more.

I guess I am putting the two together on the hard starting and the loud fuel pump. Also, when it's hard to start the car usually stutters on the first few stop and starts. But I do not get any hesitation after at all, which is what I though was another sign of a bad fuel pump - down on power.

Stealth 993

The brake pump is in that area. The fuel pump is INSIDE the fuel tank. Sounds like you are hearing the brake pump. There was a TSB about it being loud, & they put something in the line to quiet it.

On the hard start, did you check for vacuum leaks, check the plugs, wires & dist?

cgfen

hmmmmmmmmmm
1st, despite another posting the fuel pump is NOT inside the tank, (at least not on my 96 C4S). It is external and lives under the passenger's feet (LHD car).

the hydraulic brake pump is more of a "clattering" that runs for 5 - 10 seconds on initial start and whenever the accumulator pressure falls below a pre-set value (like when you brake to a stop). I thought that noise i heard at every stop was my spoiler retracting............... then i put a fixed spoiler on and the noise continued LOL on me. This pump is located in the front luggage area.

The fuel pump is more of a "buzz / whine" and runs continuously. I notice that mine gets "louder" when the tank gets below 1/4 full.

I think you need to determine which pump you are hearing before you spend the cash to replace a possibly good fuel pump.

I doubt the motorsport version would provide any benefit for a car with an otherwise stock fuel delivery system.

what do you mean by "I usually let it run for about 5 seconds and it's still sometimes hard to start the car."
do you turn the key to ON, hear the noise, wait 5 seconds then START?
If so, you are hearing the brake system pump. I don't think the fuel pump runs unless the DME senses crank rotation.


cheers

Craig

jaholmes

It is a loud buzzing / wine. I'm pretty sure it's the fuel pump. I will check the difference and different fuel levels.

I have heard that it is better on the fuel pump if you let it run for a few seconds before cranking. But if you are saying that the fuel pump doesn't do anything until you crank the engine then I'm not sure what's causing the hard start.

I have changed plugs, rotors, wires, dist when I dropped the motor last year.