is my fuel pressure right?

[Brute03]

hey guys, i'm trying to track down an on-going problem i'm having. my car idles rough, hesitates, gets poor economy and is down on power.

i checked the fuel pressure and i'm getting 26-28psi @ idle and around 38psi with the vacuum line off, are those numbers considered to be normal?

 

[DBMSTNG]

sounds a little high for a stock setup to me, but not by alot.

 

[Brute03]

high? i though it seemed a little low.

 

[blkhorse]

should be about 39 psi at 0" manifold pressure and 29lbs at 20" vacuum,so he's real close

 

[Mike97gt]

IF it drops while you are floored or under heavy load by a lot then I would look at the pump..

BUT since it seems ok

I bet you have a plug or coil concern, 99 percent of the time when these cars run rough and have the symptoms you have it's a secondary ignition concern..

Drive up a steep hill at low rpm's in 3rd or 4th gear and if this thing bucks and shudders then you have a misfire under load. If it's idling rough you might be able to tell what plug is not firing by pulling thme out and looking for the fuel fouled one.

 

[ForPointSex]

My car gets 40PSI. When my fuel pump was bad, it dropped down to 10PSI over 3500RPM. When the car was still, it showed no signs of being bad since the engine was not using enough gas for a pressure drop.


If you can, watch your fuel pressure while your driving and see if it drops.


I've also had a bad coil pack. It would miss under any load. It was fine on idle. I ordered a new one from ebay for $30 and swapped it 1 by 1 until I found a bad one.

 

[Brute03]

well i bought all new accel replacements hoping that it would fix the problem but no such luck, so that's why i think the problem might be on the fuel side