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Interesting issue I cannot seem to figure out....

I'm betting you're problem is with the plugs or wires. Even new, you can get bad ones. I have before in the past.

Mine just feels slow as hell, because of all the KR and timing dumped...
 


UPDATE:

At 1:00 am I found my pump to be at 0 PSI according to my gauge Although there was a little soemthing on there when I pulled the gauge off, nothing that was worth mentioning of course. So the fuel system drops to 0 psi in 6 hours (Started my test at 7:00 pm, pressure was at 40 psi). Good or bad? I didn't check it in between. I figure i'd do close to an "all night" test as possible. Here it is, tell me what ya think...

Shawn
 
Iron Indian said:
UPDATE:

At 1:00 am I found my pump to be at 0 PSI according to my gauge Although there was a little soemthing on there when I pulled the gauge off, nothing that was worth mentioning of course. So the fuel system drops to 0 psi in 6 hours (Started my test at 7:00 pm, pressure was at 40 psi). Good or bad? I didn't check it in between. I figure i'd do close to an "all night" test as possible. Here it is, tell me what ya think...

Shawn
Click to expand...

Ok...so if I am reading agrazela's post right...

With Key on and the FP pressurized...read it...then if you came back and it was losing pressue, and eventually reading 0psi...then he swapped out for a new one and the issue went away?

So you're looking at a new Fuel Pump...No?
 
I'm looking through my notebooks and I can't find the data from an overnight test after swapping in the new pump; however, I remember that there was still readable pressure after 8 or so hours.

One of these days real soon I'm going to get that hard data. Certainly by this weekend, because there's a guy on one of the Bonneville boards going through this exact same thing, too, and I'm trying to help him out also.
 
Iron Indian said:
I'm betting you're problem is with the plugs or wires. Even new, you can get bad ones. I have before in the past.

Mine just feels slow as hell, because of all the KR and timing dumped...
Click to expand...

So, I tryed the OBD2 and it came back with nothing... no codes at all. ??
when my wires were bad before it said there was a missfire. Now it says nothing. Any Ideas??
 


agrazela said:
I'm looking through my notebooks and I can't find the data from an overnight test after swapping in the new pump; however, I remember that there was still readable pressure after 8 or so hours.

One of these days real soon I'm going to get that hard data. Certainly by this weekend, because there's a guy on one of the Bonneville boards going through this exact same thing, too, and I'm trying to help him out also.
Click to expand...


Let me know when you can, i need to get this fixed very soon. I wanted to possibly order parts so I can have em by the weekend but I may not get the chance because of other stuff.
 
98GTPCALGARY said:
So, I tryed the OBD2 and it came back with nothing... no codes at all. ??
when my wires were bad before it said there was a missfire. Now it says nothing. Any Ideas??
Click to expand...


Any time i've had bad wires on my GTP, I never set off the misfire code but I could feel it and I knew the car was misfiring. Swapping the wires solved the problem. From my experiance, to actully set off the misfire code, You have to have a pretty bad misfire, and I mean bad. My dads GT set it once, but then again it had a wire damn near cut in half and it was running on 5 cylinders.

Don't always trust your computer into telling you how your car is, it won't always help you. It never has for bad O2s, MAFs, or plug wires....
 
ok, that makes sense, I gunna go buy a new set tonight. when I bought the car it ran fine when you put your foot down and got 2 bars on the boost gauge... any more than that and it would sputter and crap, and thats when it said I had a missfire. but when I went to change the plugs and wires the first one I touched, the wire fell off the boot! Thanks for the help, I let you know how it turns out.
 
Just to touch up on the misfire thing. As Dave discovered last year, almost all of the PCM's that are preprogrammed with the P0300 code removed for cams etc. They will NOT show any type of misfire what so ever! The P0300 apparently controls the entire spectrum of detecting a random misfire and a multiple misfire. What complicates this even more is if you have a cylinder that's completely dead, it won't even show up on a scanner.

sux
 
Both of my PCMs still have the misfire stuff activated, I wanted that to stay in there since i'm still on my stock cam on both vehicles, why delete something when I don't need it gone? And i've tripped P0300 on accedent a time or two myself (not having a plug wire on or something) so it works.

In my experiance, even when I still had a stock PCM, and i felt a misfire, i never set anything off...
 


Could it be a bad fuel injector? I didn't read everything here, but we had the same fueling issue on a friends car and he later determined it was a bad fuel injector, but I'm not 100% sure.
 
UPDATE:

Today I ghetto "rigged" up a fuel pressure gauge to the schrader valve on the fuel rail tapped the gauge on the windsheild and did some driving.

At WOT, my FP is only at 42 psi. What happens is when rolling into the throttle to go into WOT the fuel pressure starts to raise into the low 50s then when the motor is at around 4,000 rpms the fuel pressure suddenly drops down to 42 psi and of course the knock begins.

Am I pretty safe to say at this point the problem is the fuel pump? I want to make damn sure before I drop the coin on one. I did swap FPR with another one I had (unknown if its good or bad) and the problem didn't change. I also swapped injectors with no change either.

Let me know guys. I'm ready to finally get this resolved for good!
 
Most likely it's your fuel pump. I don't want to be the one who calls it 100%, but I don't see what else it could be.
 
Sounds like your fuel pressure is doing exactly what mine was doing in that graph I posted on the first page, the "before-and-after" a new fuel pump.

Were I in your shoes, I would get a new fuel pump.
 


UPDATE:

I totally forgot about this thread, I figured i better update it. The problem ended up being the fuel pump. Now with a new fuel pump it runs 0 KR like it should and the FP stays up and so do the O2s.
 
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