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1999 gtp bogs at wot

C

circa09

New member
Hey guys looking for some input ive got a 1999 Gtp looking for input it bogs down at wot only. Other than that runs great. Thrre are no codes being thrown. Kinda feels like a misfire.. anyway pulled vaccuum line off fuel pressure reg and replaced it ( it was cracked ) still no fix. So i checked My fuel pressure and it is at 48 49 with key Turned forward then when I start her up it goes to a steady 45 what ya think?
 


How many miles?

Sounds like a clogged cat.
I'd start by checking plugs and wires though. If that doesnt help any then you can remove the o2 sensor to give the exhaust gas an alternate path. This is enough to let the exhaust out if the cat is clogged. If it runs better then the cat is clogged. If it stays the same then your issue is somewhere else.
 
Just did plugs and wires on 120 k miles rechecked plugs and wires and they look good.. gapped correctly. The fuel orange needs to be between 48 and 55 psi so i am a little low
 
Little low, may consider replacing the fuel filter sometime soon if you haven't already. But I doubt that would be the issue.

May try as said to pull the front 02 sensor, and take it for a drive. It will be louder, SES light will be on but it will let you know if the converter is getting clogged.

Otherwise I would suggest checking and making sure there aren't any other vacuum leaks. Take some B12 spray or similar and go point to point on the hose connections, if the engine revs up it needs to be replaced. The leak may not be much during normal driving but at WOT it could be enough.
 
Extend your pressure hose and go for a drive while monitoring pressure. I've seen a few older pumps test good at key on and idle. When you demand supply though..they fall on their face.
 


Filter just got changed took parts cleaner by vaccuum no leaks anywhere tries o2 sensor just through o2 code so cats not clogged dont think it would be the diaphram on fuel pressure regulator do you?
 
I just pulled the vaccuum line off the fuel pressure regulator and no gas came out when it so i actually dont think the diaphram is bad...
 
Okay. There is no gas coming from the fuel pressure regulator when I started it up and pulled the vaccuum line off. So i dont think diaphram now. When I pulled the o2 sensor out it made no difference just through o2 code. Is that good enough for punctuation? Not looking for help with sentences looking for help with my car. Its a new phone im on and not used to it yet.
 
And we're trying to help fix your car. When you have one big run on sentence it makes it hard to understand.

So. Plugs and wires are ok. Fuel filter has been replaced. FPR you think is good.

Just to make sure you pulled the front o2 sensor right?

I'm kinda agreeing with Bill. The pump could be one its way out. Mine died at 135K.
 


Thing is guy.. it's much easier for us to help when we can understand what you are saying. I read it ...didn't think I had an issue and you know... I had two or three of the things you tried saying totally wrong and would have made a bad suggestion to you based on what I thought you meant.

Now that I read the punctuated version, I am wondering..do you hear anything that might sounds like a clogged cat? Clogged cat's don't typicaly throw codes.
 
I'd still like to hear back about the possibility of a road pressure test. I understand it might be tough for some, as the hoses aren't easily extended.
 
Connect hose, run under hood, shut hood, tape to windshield with DuctTape... drive and multi-task between driving and watching gauge without killing anyone.
 
I apologize and completely understand. My phone is correcting everything wrong. Just troubled with this issue. And I tried pulling both o2 sensors and neither made a difference. And my fuel pressure tester im using is from work at its not Long enough to reach unfortunately.
 
So i pulled the vaccuum hose off the fuel pressure reg while it was running. I have thee fuel pressure tester hooked up and it went up from 42 psi to 50 anymore thoughts?
 


Okay so just bought a magnaflow cat 2.5 inlet and outlet will that Bolt up right? I think you are all right about the cat.
 
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