fpr[3.3] [Archive] - SaabCentral Forums

: fpr[3.3]


finga
20-05-02, 02:57 AM
Am i right in assuming that if the fpr is faulty then not enough fuel is being delivered and then your car would not boost properly?seems logical but not sure thanks.[learner]

Johann F
20-05-02, 03:44 AM
It's one explanation at least - 'faulty' boost has many causes though - any other symptoms?

finga
20-05-02, 07:43 AM
THANKS JOHANN,WELL A COUPLE MTHS AGO I WAS SMELLING FUEL IN THE ENGINE COMPARTMENT WHICH I COULD ALSO SMELL IN THE CABIN.WHAT I DISCOVERED LATE LAST NIGHT IS THAT MY FPR IS LEAKING FUEL ALS WHEN I DRIVE THE CAR HARD[CARLSSON 900]AND THEN EASE OFF THE PEDAL THE REVS DO A DRAMATIC DROP,NEARLY SHUTTING OFF AND THEN PICKING BACK UP AGAIN.i was achieving at least a qtr/half in the red on apc .can barely touch it now

<font size=-1>[ This Message was edited by: finga on May 20, 2002 12:46pm ]</font>

Johann F
20-05-02, 07:53 AM
Yep - sound like you have identified the fault correctly. The diagphram has probably ruptured. It's an easy job to replace - you might want to instal a rising rate unit in place of the standard fixed unit - I can't garantee an increase in outright power but in my experience it will certainly give you smoother power delivery and a quicker throttle response if it's set up right.
Err - and don't delay as you don't really want fuel squirting about in the engine compartment and a very lean running engine will destroy valves.

finga
20-05-02, 11:04 AM
sorry johann i forget to tell you my fpr is 3.3 which i got from trent saab.i can,t remember if its rr or not.can it/should it be repaired and set up again?

Alex
20-05-02, 03:19 PM
I thought Trent sold RRFPRs and 3.3 bar ones came from Abbott.

Failure of the diaphragms isn't that unusual.

finga
20-05-02, 04:00 PM
thanks alex,i checked and yes my one is the r/r fpr.What are the arguments for fixed fpr's or r/rate fpr?I'm gonna change mine now but which road to go down?

Alex
20-05-02, 05:01 PM
Theres a previous post somewhere on this subject. The 3.3bar reg from Abbott is extremely expensive (160+vat) and of limited benefit, the extra fuel from the higher pressure is only delivered at WOT once the ECU moves off its AMM controlled delivery.

The RRFPR is cheaper, and also allows the extra fuel to be delivered during snap throttle openings and highish boost conditions under part throttle.

Both are cheapish fixes if the performance envelope isn't being stretched too far.

Johann F
21-05-02, 06:08 AM
Finga,
You may be able to get a replacement diaphragm as the unit is dismantleable/repairable - check with Trent.
I would always go with the RRFPR as it's adjustable - and every Saab is slightly different when it comes to which base setting it's happiest with.