1996 850 2.5 20v Fuel pressure?

Beastu · Post by **Beastu** » 25 Apr 2014, 01:06

Hi,

I was wondering if anyone knew the stock fuel pressure on this car, my car is running pretty weird and seems like its not getting enough fuel. But how much fuel pressure is it supposed to have?

Thanks in advance.

Post by **misha** » 25 Apr 2014, 01:49

43.5psi after 1st prime without starting the engine,around 35psi with engine idling & again 43.5 psi on full throttle.
Everything around 35psi is acceptable.

Beastu · Post by **Beastu** » 25 Apr 2014, 02:01

So if its running 43.5 on idle and 51PSI on full throttle it is bad? and this might explain why we think its not getting enough fuel?

Post by **misha** » 25 Apr 2014, 02:37

With 51psi you have more pressure.With that pressure the engine will not starve for fuel.

With that pressure,i guess,fuel pump isn't stock.Do you have high performance fuel pump installed?

It's either that or the fuel pressure regulator is stuck,but could also be a clogged fuel filter.

Beastu · Post by **Beastu** » 25 Apr 2014, 02:39

As far as i know i dont have a high performance fuel pump... Its not long since i took the ownership of this car and i havent really looked at the fuel pump

So if the fuel pressure regulator is stuck then the car might be running unsmooth? Its an auto transmission btw(does this affect the fuel pressure?)

Post by **misha** » 25 Apr 2014, 02:48

Transmission doesn't affect fuel pressure.
Do you have check engine(lambda) light ON?

Bad Fpr can affect performance,but with that pressure you have ...can't.It would affect if fuel pressure is low.

Beastu · Post by **Beastu** » 25 Apr 2014, 02:56

No error codes show up in the dashboard :/ The car is acting like this... When in park it is running relative smooth, but in D(drive) with the brake in its running really unsmooth goes from 700-1100 RPM and shakes. But its running pretty smooth if i start it the morning after. If i try to push the gas pedal all the way inn rapidly the car will shake and have very little power. If i press it slowly in it accelerates at normal speed. It gets worse the more i have driven the car that day.

Post by **misha** » 25 Apr 2014, 03:06

I would replace spark plugs,ignition cables and inspect cap & rotor.
Spark plugs only oem Volvo,set of 5,wires Bougicord and cap & rotor only Bosch if they need to be replaced.
I think that those things are making problems.
Does the Lambda light come on on Check when key is in position II?

Beastu · Post by **Beastu** » 25 Apr 2014, 03:43

Cant remember seeing the lambada light when in position II, not that i was looking for it... hmmm... gonna check when i am off from work, thanks for help

Post by **misha** » 25 Apr 2014, 04:07

If not,then it is burnt or removed from the dash.
From your description i realize that the engine is misfiring and ignition parts must be replaced.
Stage "0" must be performed.