Fuel pressure way too high

[Danny-Boi]

Hi, I recently brought my car to the mechanic and he replaced the fuel pressure regulator, he told me that the fuel pressure was at 89, and asked if the car had an aftermarket cam. I am not sure if i do or not because i bought the car used. Does anyone know why the pressure is so high?
Thanks

 

[88stangmangt]

well the stock fpr is not adjustable................... so ????

 

[Danny-Boi]

Yea i know its not adjustable but is there anything else that has a factor in the fuel pressure being high?

 

[88stangmangt]

no since it all starts there i cant see how it was so high maybe he made a mistake? even a bigger fuel pump would no have caused it to be so high because it is still held back by the stock fpr.

 

[PRO50SC]

Has the return line been checked to see if it is blocked or pinched? That would cause excessive pressure. What did the tech have to say about it? Cam size has no effect on pressure.

 

[88stangmangt]

PRO50SC-what does being ASE certified pay? im sure it is very decent i would like to know for reference. thank you!!!!

 

[Starscream88]

Are you 100% SURE he said 89psi???

Thats REALLY REALLY high

Im actually wondering if it would even run at that level
Have you been getting check engine lights?

You could have REALLY damaged your injectors if indeed 89psi was what they were running at,

For comparison a stang from the factory runs anything between 32 and 40 psi Max And most Stangs with Mods only run that anyway,

Id say either a blockage, or a really messed up Fuel pressure regualtor,
And I wouldnt reccomend you use the car untill thats fixed

 

[BlueDevil95]

89!!!! the stock fuel system components will not be liking that for long. if the pressure was that high on a stock car, it wouldn't run. i think he pulled the wool over your eyes.

 

[Starscream88]

89!!!! the stock fuel system components will not be liking that for long. if the pressure was that high on a stock car, it wouldn't run. i think he pulled the wool over your eyes.

Either that or you misheard him,

if he really did say 89psi ask him to check your Muffler Bearings,
Also while hes at it ask him how much he charges for headlamp fluid

 

[88stangmangt]

what is a muffler bearing?

 

[Starscream88]

what is a muffler bearing?

Your joking right?

 

[djk8705]

haha yes if hes that dumb of a mechanic he wud say ya sure... i think hes just gettin at the fact that he musstt have miss read the pressure... btw is 48 too high? with a H/C/I combo with 24's and a fpr... good luck

 

[Danny-Boi]

I am pretty sure that he said 89 but i am starting to think he didnt if you guys are saying it is serious. The car runs pretty normal except for if i am driving for about 30 min it will start to hesitate. I will most likley get a pressure gauge and see for myself.
Thanks

 

[TheUser]

he probably said 39..i'm pretty sure you'd smell fuel and your injectors/rails would hissing pretty loudly if it were much more than 45-50

 

[88mustangGT]

ya my fuel pressure was way high about 45-50 range and fuel would come out of the little hole in the fuel injecter and they would make a werid little ticking/hissing sound, i could only imagine if it was 89 i dont think its possable. maybe he just wanted to make more money that day.

 

[Danny-Boi]

well I doubt he wanted to make more money because he didnt charge me. I will get a guage and see for myself.
Thanks