Random P0172 And misfire below 700 rpm
#31
02-16-2010, 05:26 PM
Welp, I replaced the sensor and it runs GREAT. It still has the occasional misfire at idle. But, it's to the point where I cannot tell it is happening in the cab. I can only hear it at the rear of the truck, and I don't think I would even notice it if I had a normal muffler. It still smells a little rich. I'm going to check the fuel pressure soon. and check out the intake manifold for signs of leaks. I think I might still have an issue. But one so minute it's ridiculous.
#33
02-17-2010, 04:40 PM
those plugs indicate that more than likely your FPR leaking inside the intake. check it the cheap way like i did. since you have a 95 CPI engine, take off the intake manifold tuning valve by removing the 2 screws that hold it on top of the intake and pull it out of your way, and then grab a good flashlight and look inside the intake for small puddles at the bottom of the intake. also look at the FPR to see if it looks clean or other signs of leaking. if you find any of these decribed, well then your FPR is leaking cause misfires!!!
Nevermind...found it lol.
Ok guys...what do these mean to you? I did the best I could with the pictures.
More pictures here:
http://s578.photobucket.com/albums/s...inator/Intake/
That first picture of...whatever that is...looks wet. Thanks in advance.
Last edited by swartlkk; 02-17-2010 at 05:07 PM. Reason: *Combining Consecutive Posts* - Please use the EDIT function to add additional information to your post if another member has yet to reply.
#38
02-20-2010, 01:07 AM
Welp...I took off the plenum. You think I had a leak? Haha.
I turned the ignition on while I had the plenum off, and watched the fuel pressure regulator leak like a sieve from the adjustment screw. I replaced it, cleaned everything up, and put it back together. I tested to fuel pressure while it was running...it was at 54 PSI during idle, and would jump to about 60 if I gassed it. Runs and idles smoother than silk. I have loads of extra power. I can't wait to see what gas mileage I get. (I was averaging about 15 MPG) Problem solved. Thanks to everyone for your input and help. =)
I turned the ignition on while I had the plenum off, and watched the fuel pressure regulator leak like a sieve from the adjustment screw. I replaced it, cleaned everything up, and put it back together. I tested to fuel pressure while it was running...it was at 54 PSI during idle, and would jump to about 60 if I gassed it. Runs and idles smoother than silk. I have loads of extra power. I can't wait to see what gas mileage I get. (I was averaging about 15 MPG) Problem solved. Thanks to everyone for your input and help. =)
#39
03-06-2010, 12:59 AM
Welp...I took off the plenum. You think I had a leak? Haha.
I turned the ignition on while I had the plenum off, and watched the fuel pressure regulator leak like a sieve from the adjustment screw. I replaced it, cleaned everything up, and put it back together. I tested to fuel pressure while it was running...it was at 54 PSI during idle, and would jump to about 60 if I gassed it. Runs and idles smoother than silk. I have loads of extra power. I can't wait to see what gas mileage I get. (I was averaging about 15 MPG) Problem solved. Thanks to everyone for your input and help. =)
I turned the ignition on while I had the plenum off, and watched the fuel pressure regulator leak like a sieve from the adjustment screw. I replaced it, cleaned everything up, and put it back together. I tested to fuel pressure while it was running...it was at 54 PSI during idle, and would jump to about 60 if I gassed it. Runs and idles smoother than silk. I have loads of extra power. I can't wait to see what gas mileage I get. (I was averaging about 15 MPG) Problem solved. Thanks to everyone for your input and help. =)
#40
03-08-2010, 02:00 AM
I replaced the fuel pressure regulator, plenum gasket, and while i had easy access to it, I replaced the EGR valve gasket. I cleaned the plenum (very carefully) with carburetor cleaner and 1,586,359 shop towels.
Disclaimer: any numerical figures may be exaggerated slightly.
Disclaimer: any numerical figures may be exaggerated slightly.