What OBDII wont show?

[holyford86]

I don't believe the OBD2 system can sense fuel pressure.

I know I lost the fuel pump in a 2000 Focus and it never threw a light, or any codes.

It depends on the application, I know atleast some of the newer 5.4s can do it.

 

[adsm08]

Everything after 2003 should be able to.

 

[Jason]

Dont really wanna argue, but it wont trip a code until the fuel trim numbers or air flow numbers or some other pre set caculations are out of range. Which means you may not be able to tell the engine is running poorly bt the computer has specs and if the numbers are not within specs you get CEL.

You just agreed unless you left a paragraph out.

 

[JackLikesTrucks]

Well, tested with a fuel pressure gauge.

My son hooked it up to the Schrader valve, let her idle for about ten minutes and she went dead over about 3 seconds. He saw the fuel pressure go from 65 to 15 to 3 and went dead. Just like that.

So the engine is cutting out from fuel starvation. Only thing left is to replace a fuel relay or PCM.

But I already rotated it out with the other modules and no change.

Ugh.

What do you guys think of the 97-2000 Wranglers?

 

[modelageek]

when you replaced the fuel pump did you replace the whole unit with the fuel pressure regulator on it. I have posted about 4,000 times on these forums. I have never once posted that i think the pcm is the issue( I think people throw that out to much for the number of times it actually is the issue.) look around the pcm and see if you see any corrosion, someplace it might leak. If you have a new filter, new/tested relays, new pump and fuel pressure regulator. Any chance that the fuel line is kinked. if all that is checked out maybe you should consider the pcm or the chance that you got a bad replacement pump

 

[mentalbreakdown00]

just because a pump is new does not mean its any good....