Engine/Transmission (1998.5 - 2002) Electric Fuel Gauge installed- Funky gauge readings...

[fkovalski]

I installed a set of gauges this weekend. Auto Meter boost and pyro, Westach electric fuel pressure- 3 pod, A- pillar. I am running a stock lift pump. 63K on the truck, 13k on the pump.



I am trying to determine the funky fuel pressure readings:

It will read 13-14 psi on start up and drop to around 9+ under acceleration (as I would expect. )



BUT- arbitrarily it will drop to around 6 or 7 at any given time! This can happen when cruising or at idle when stopped at a light. The funny thing is that when I rev the engine at an idle it will bump right up to 14 psi. Given time, the needle will go back to 14 on its own. It will read as expect then drop again. There is no "cause and effect" relationship that I can establish. I am wondering if it is a bad sender or gauge. I do not think it is the pump because of the reading going up to normal when revving and the occasional "normal" readings. Plus at times it seems to react as I would expect the reading to be.



I installed the sender at the fitting on a new cap at the fuel filter. I have checked and recheck my wiring. I know that the grounding is crucial in this setup and have it grounded directly from sender to gauge and at both end as well. The sender being directly grounded to the NEG at the battery.



Would someone re- affirm to me that this tap for the sender is pre- filter pressure? I am going to replace the filter this weekend to try and eliminate the filter being the cause.



One question is this: if it were a bad lift pump, would I see the reading as described? The puzzle is the bumped up reading when revving.



Any and all feedback is appreciated.

-frank.

 

[amsoilman]

I installed a set of gauges this weekend. Auto Meter boost and pyro, Westach electric fuel pressure- 3 pod, A- pillar. I am running a stock lift pump. 63K on the truck, 13k on the pump.



I am trying to determine the funky fuel pressure readings:

It will read 13-14 psi on start up and drop to around 9+ under acceleration (as I would expect. )



BUT- arbitrarily it will drop to around 6 or 7 at any given time! This can happen when cruising or at idle when stopped at a light. The funny thing is that when I rev the engine at an idle it will bump right up to 14 psi. Given time, the needle will go back to 14 on its own. It will read as expect then drop again. There is no "cause and effect" relationship that I can establish. I am wondering if it is a bad sender or gauge. I do not think it is the pump because of the reading going up to normal when revving and the occasional "normal" readings. Plus at times it seems to react as I would expect the reading to be.



I installed the sender at the fitting on a new cap at the fuel filter. I have checked and recheck my wiring. I know that the grounding is crucial in this setup and have it grounded directly from sender to gauge and at both end as well. The sender being directly grounded to the NEG at the battery.



Would someone re- affirm to me that this tap for the sender is pre- filter pressure? I am going to replace the filter this weekend to try and eliminate the filter being the cause.



One question is this: if it were a bad lift pump, would I see the reading as described? The puzzle is the bumped up reading when revving.



Any and all feedback is appreciated.

-frank.

MOVED thread at the request of the member to 24 Valve Engine and Tranmsission (1998. 5-2002)



Wayne

amsoilman

 

[darkhorse]

If you are using the new aluminum filter cap, the tap is post filter. Your fuel pressure relief valve may be acting up.

 

[trqmnstr]

I just ordered the Westach FP and billet filter cap myself. Is this a good place to read FP. I hope I didn't make a bad purchase. Thanks

 

[fkovalski]

Thanks for the info about post filter reading.

... Your fuel pressure relief valve may be acting up.

Can you enlighten me more about the "fuel pressure relief valve. " I do not recall reading any threads about this.



trqmnstr- I went with this set up for the ease of installation. I did not want to deal with a mechanical gauge and I feel that the electric is a decent setup once this fluctuation issue of mine gets cleared up.