This is on a 2001 Mustang GT. The fuel pressure moves from like 40-50 psi. Is this normal? It doesnt change under normal driving conditions. When I put it in park it went up to 50 psi and sat there and then I put it back in drive and it stayed there after driving it for 10 minutes at 40 psi. Is this ok or is there something wrong? Reason I am asking is because I get pinging at 4,000 RPMs and over with 3/4 throttle applied.

 

Those are failrly normal numbers, my '03 GT runs mid 40s tolow 50s at high loads an 75% to WOT.[/align][/align]Back off the spark advance in your tune, or add some fuel...[/align]

 

Yeah that is normal.Try backing off your timing,if you can't do that, add some octane booster until you fill again.You may have gotten some bad gas or you have a big intake leak.

 

Octane booster LOL. You better buy about a gallon of that crap if you want to go from 87 to 88. Thats ricer juice, it doesnt do anything.

50psi at idle is not normal. 30psi at idle is. 40psi at cruise is normal. 45psi at tip in is normal. 50psi is not normalunless you have uped your pressure.

How are you reading this? Through a gauge or datalog?

 

Change your fuel filter. Mine was very irratic, between 38 and 55 psi as read through an Aeroforce Interceptor scan gauge. After the filter change it hasn't dropped below 40 or gone over 52 that I noticed. 52 on a cold idle and 45ish at normal engine load cruising. This is on a stock pump.

Oxford, what pump are you running?

 

Oxford,Anywhere from 44-52 is normal at idle(I should know im a Ford tech).I simply suggested the octane booster because he doesn't have much other choice if he can't change his timing.Please, I dont want to argue with you about this but to say 30 at idle is normalis way off and your gonna make him try to solve a problem he doesn't have.He has a bamachips tune which is most likely only mail order,which never ran on the dyno and never got an accurate A/F for his car.Most likely he just didn't put 93 in it or he got bad gas or the tune has to much timing.

 

My fuel pressure gage does the same thing. Normally idle is at 30 psi, cruising is at 35 psi, and it goes higher at WOT. With the weather warming up I've notice that in town idle fuel pressure has started running higher and higher. First it was 40 psi. Then during even warmer weather it was 50 psi. It has even hit 60 psi when I was stuck in traffic. I was worriedabout this so I took the car to Ford and had it data logged. They found nothing wrong. According to them cold idle was 43 psi and hot idle was 53 psi. But the fuel pressure gage kept doing the same thing.ThenI was told by Trick Tuners that this is normal. That as the fuel rail tempature increases, the computer increases the fuel pressure to avoid getting vapor in the fuel rails.

 

I guess you guys are refering to pressure without vacum reference. With vacum its 29-30 at idle with out vacum its 39-40.

 

I've been wondering if the location of the Autometer sending unit makes a difference. Mine is located on far front end of the passenger side fuel rail. I'm assuming this is normal but I've not seen any other installations.

 

Mine is mounted at the FPS. Don't mind the wires its all temp since the motor gets pulled when I get home.

Mounting it at the service port shouldnt be a problem.