My fuel pump started making this wierd howling noise. It's intermittent, and only does it some days. At least I think it's the fuel pump. It's coming from the underside of the car, near the right rear wheel, and the only moving parts back there are the wheels, suspension, and fuel pump, and it's definitely not a wheel or suspension noise (it made the noise when i was parked, engine running), it must be the fuel pump, right?

Anyone encounter that sort of thing? Should I replace my fuel pump?

 

My 1991 1CQ sometimes makes this noise as well. It is difficult to describe how it sounds but on few rare occasions I noticed it only when I drive. It doesn’t seem to matter if the tank is full or almost empty. I think it is the check valve and not the pump itself. The pumps are noisy as they are located at the bottom of the tank and transmit the sound rather well. I have heard that replacing the pump doesn’t make things quieter. What year and model is your car?

 

I had a noisy pump in my 80Q, but it was all the time. It got me pretty worried (and it was embarrassing to be able to hear the fuel pump over then engine idle 30 feet away lol) so I replaced it before it failed on me, and the replacement was much quieter, not to mention better performance. Im not sure if you need a fuel pump, but if you do decide to change it I would buy the pump off ebay. (I an OE Bosch Pump for 130 New) Also have you noticed any hesitation, hard starting, or any performance problems since the noise has started? If it were me I would wait to see if the problem became worse as the pumps to buy from retail are 250 plus for a decent brand pump. Also when is the last time you changed your fuel filter, and have you checked your fuel lines for any kinks or corrosion?

 

It's either an 89 or a 90 depending on which mechanic you ask and how they interpreted the VIN. It's always started hard, but just recently started making the noise (or at least i only just recently noticed it). Doesn't seem to have any hesitation or performance problems. The fuel filter is relatively new, maybe 10k miles on it. Never noticed anything on the lines, but then I haven't been under that part of the car yet. I'll give it a look-over when I change my oil this weekend.

 

I noticed that many CIS- injected cars have a hard time starting. This is probably due to the fact that it takes some time to get the system fully pressurized. You will probably notice easier starts when you turn the ignition on and wait a few seconds for the pump to cycle on and off, then proceed to start. When you crank the engine the voltage drops a bit decreasing the pump’s performance. Hard starting could also be the result of bad temperature sensor, cold start injector, or cold enrichment system. If the pump is putting out the required pressure and volume, I don't see the point in replacing it.

 

i was just worried that the noise might be a prelude to failiure, and i'd hate to lose pressure out on the freeway. It's not like I can walk to the nearest Kragen and pick up a new pump like I could for a Mustang or Civic

I'll try the turn-wait-crank trick next time, too.

 

I have heard Bosch pumps lasting 250K or longer and I have heard them fail after 30K. The quality of fuel determines the life. These pumps are noisy. What I know for a fact is that if the car sits for a long time, condensation builds up in the tank and kiss that pump goodbye. They rust extremely easy and I would never get one from a salvage yard. As far as your worries about failure, there are other things which will leave you stranded, like a bad hall sensor in the distributor. Mine started failing intermittently and it took me three weeks to finally solve the problem.

 

the turn-wait-crank thing doesn't seem to work for me. The pump doesn't cycle until i'm actually cranking the starter.

I'm not too worried about condensation. This car never sits for more than 18 hours or so.

Where's the hall sensor/what's it do? Is it a common failiure?

 

The hall element is inside the distributor. Mine started going by just randomly dying on the highway without warning. Sometimes it would restart right away other times I would have to sit from 15 minutes to 3 hours. I heated mine with a heat gun but couldn't get it to fail, after getting towed twice I made several test lights. I drove around until it failed. I used some "cold shot" to cool it down and it started to work. Next day I had it replaced. The hall element is not available by itself you have to buy a complete reman distributor.