[cover3]

Hi i have 99 v6 mustang having trouble, car is bucking at high rpms, has no power, bogging and dieing out, tried many things. sometimes spits through the intake and pings like running lean, but car starts first flick of key and idles pretty good

-had code for DPR valve for a long time, replaced when this started happening
-replaced vent valve
-egr valves not sticking
-new plugs/wires
-not misfiring
-checked to see if cats where blocked
-got code for MAF intermittent, tried 3 maf sensors, still same

i had a new fuel filter put on 2 months ago, its like its not getting its fuel so checked the filter and it was blocked bad, brown gas in it and dirty, replaced the filter and still the same thing, so checked fuel pressure on the rail and it showed 28 pound idling, would go to almost 40 wot, when it was at 28 pound idling, when you give it a bit of throttle and let go it would drop down to about 20 pound for a second and go back to 28. Judging by the fuel filter and the fuel that come out of the line the tank its pretty dirty.

What is the fuel pressure supposed to be on the fuel rail? Could this be a bad pump? Could the screen in the tank be blocked up? Could anything else cause this?

[shinerstang]

It sounds like something is going on in your tank. It is starving it of fuel. Either the basket is clogged, or your tank is filled with crud. Your MAF is trying to add more gas, but it is not letting it.....

[cover3]

So i dropped the tank this morning and removed the pump and the tank wasnt gritty or dirty but it did have ALOT of brown/rusty looking water in it. When i gets a way to get some fresh gas Ill see how it runs again

[shinerstang]

If you have time and the fuel line tools, I would disconnect your fuel line up front and blow the crud out before putting the tank back in.....

[cover3]

What is the fuel pressure supposed to be at? Is it supposed to drop down to almost 20 when you let off the gas? is it supposed to be at 28psi idling?

[shinerstang]

It should be around 30 or so at idle. It may drop down for a second, but should go back up immediately......

[cover3]

it was at 28 idling, when i give it a quick rev it went up a bit and then down to 20 for a second then back to 28 again

[shinerstang]

Originally Posted by cover3

it was at 28 idling, when i give it a quick rev it went up a bit and then down to 20 for a second then back to 28 again

The FPR is doing it's job then......

[cover3]

After draining all the water in the tank the car ran near perfect for like a week but now its not running right again, like it starts, and idles perfect and can drive up the road slowly without ease, but on highway and passing people the car will sputter and sometimes even stall out leaving me to pull over, but then the car starts right up again. I checked and there isnt water in my tank and the fuel filter isnt clogged. Could my fuel pump be bad?

[shinerstang]

I think your fuel system is all bunged up. Are you getting any seepage through the tank itself? I mean, is it leaking or is water somehow getting into the tank when you drive in the rain? I know salt is a killer on our cars, I used to live up North.....

Did you blow out your fuel lines? I would have replaced the pump while I was in there. But sometimes you can't see those things coming.....

[ChuckV10]

Have you looked into the injectors? You might have 1 or more that are plugged or have failed.

If you have a mechanic stethoscope you should be able to hear the injector clicking. If you have no clicking than that injector has issues for sure.