Low Fuel Pressure Light Constant On

[montelatici]

Fuel pressure light stays on. Replaced the gas tank filter with a new one from IAP, looked a little different than the one on the car, but I assume its flow characteristics are similar. Light still stays on. I also bought the cartridge filter but haven't replaced it, but I am assuming that even if clogged it would not affect the pressure measured by pressure sensor anyway, or am I wrong. Intuitively, I would assume that if the cartridge filter were clogged the pressure sensor would see even higher pressure. How often do pressure sensors fail? How often is a seemingly nicely whirring pump not provide the necessary pressure?

Thanks,

Alfredo

[Roadtrip]

If you squeeze the input fuel line to the Injection pump, does the light go out? If so, it's likely a weak/failing supply pump.

With the light on constantly, I would expect poor performance from the engine (missing, loss of power, etc.) Do you have any of these symptoms?

Take the gas cap off, does it hiss indicating a vacumn in the tank and a blocked vent system?

PM me your email address and I'll send you a diagnostics guide to the fuel supply system.

The pressure light sensor is downstream from the front fuel filter, so if it were clogged, you WOULD get a low pressure light.

[montelatici]

Yes, it does not run correctly. I am pretty sure it is the fuel supply to the injection system, just trying to determine if the tank pump is ok or not. I will first replace the cartridge filter then if it does not sovlve the problem I will try the squeezing trick. If the light goes off then I guess it is the pump. My email is montelatici@aol.com.

Grazie,

Alfredo

[Sniady]

Did the light just randomly turn on one day? Or did you work on something, and a couple days later it turned on?

I would check wiring.

[montelatici]

No, bought the car with constant red light. PO didn't know what light meant.

Ciao,

Alfredo

[jackwalduck]

Any luck on solving this problem? My 78 spider is behaving similarly so was curious as to the end result.

Many thanks,
Jeff

[Keven]

Also make sure your fuel tank evaportation system is working correctly. If its not it could creat a vacuum in the fuel tank and make it hard for the fuel pump to work.
When you remove the fuel cap, is there a wooshing sound? If so the system is creating a vacuum. I think that there is a check/one way valve on a tee near the recovery tank where the jack mounts in the trunk that tends to fail.

[Roadtrip]

Jeff - PM me an email address and I'll send you a troubleshooting guide for the fuel supply system.

[jackwalduck]

Keven - I just checked and no sound of air from the gas tank. will continue to monitor that.

Roadtrip - PM is on its way.

Thanks!