Fuel Pump Threw Low Pressure Codes

[GMBoy]

Originally Posted By: another Todd
Mine is a 1996 with the F53 chassis, 460 cu in.



Exactly what my Dad has. He upgraded it with a "Bank's System" and let me tell you - that really woke it up!

 

[another Todd]

My mods include in order:
Removed fresh air intake hose from the air cleaner. No noticable difference.
single 3" exhaust with Flowmaster muffler exiting in front of rear wheels. Produced a noticable improvement.
Crane multi spark ignition and coil. Produced a very noticable difference especially from a stop.
Banks headers. Produced a small difference.
Gear Vendors overdrive. Produced a huge difference when towing over hills as now I have an 8 speed transmission. The split between gears now is about 500 rpm vs. 1000 rpm stock.

 

[TallPaul]

"Banks Headers. Produced a small difference."

This just confirms to me that on modern vehicles, unless you are reworking the whole engine, just do cat back. Actually muffler alone can be the big plug. On my '95 4.9L F150 the stock muffler was a huge cork. I put a Flowtech Raptor on ther and got rid of the lengthy over the axle tail pipe, and she felt much better and sounds a whole lot better.

As for this Chevy motorhome, has 3" pipe from each cylinder bank, then Y's into single pipe at 2.5"! That makes no sense, bet I could get tons of power by opening that up.

 

[TallPaul]

Whelp, here it is two years later and it lit the Check Engine Soon light again, right after a fillup (43 gal on 55 gal tank. Stayed on, but drove fine, the whole tank, then shortly (within a couple miles or so) after the next fillup (43 gal again) the light went out and has stayed out for several hundred miles. weird! Would be nice if it would telly you what actually happened, instead of just a general light.

 

[Vikas]

So, put the code reader on it and read the stored code.

 

[TallPaul]

Originally Posted By: Vikas
So, put the code reader on it and read the stored code.
Next time it's in the shop I'll have it done. I just thought it odd to come on only for the one tank of fuel. Probably coincidence. Actually didn't think it would go out until reset, but apparently when the problem is gone the light goes out.

 

[Vikas]

Assuming the codes were P0171 or P0174, first thing to try would be CRC MAF cleaner spray *before* doing anything else.