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Posted: Wed Oct 28, 2009 11:49 am
by Charlvdw
Andrew.200SX wrote:What is the easiest - cheapest way to check the fuel pressure and fuel pressure regulator ?
I paid R350 +- for my fuel pressure gauge and R450+- for my adjustable FPR with a gauge, i think the choice is simple.

Posted: Wed Oct 28, 2009 11:52 am
by Andrew.200SX
From who did you get them ? I am getting a bit gatvol of trying to guess what the fault is with my beast.

Posted: Wed Oct 28, 2009 11:59 am
by Charlvdw
Andrew.200SX wrote:From who did you get them ? I am getting a bit gatvol of trying to guess what the fault is with my beast.
Zack got the gauge for me from auto styling and the fpr i bought from ABL imports in Boksburg.
http://motorcade.co.za/index.php?main_p ... cts_id=456

Posted: Wed Oct 28, 2009 12:06 pm
by Andrew.200SX
Thanks.

What about this : http://www.autostyle.co.za/product/1778 ... ator(red)/

any ideas on what the quality will be ?

Posted: Wed Oct 28, 2009 12:53 pm
by Charlvdw
Looks o k , probably the same quality as the one ive got. Just keep in mind the R75 shipping cost from them and if it go's faulty you cant drive round there and have a asre shuffing.

fpr

Posted: Mon Nov 02, 2009 10:59 am
by acemine
i seem to be having the same problem, boosting .9 bar, 76mm exhaust, changed coil packs, did timing, cleaned lines, replaced all vacuum hoses and and and . . . ..
guess wat, same kak, if i swith off while driving, then back on she motors. . . for a short while then tada, holds back, put a fp gauge in this weekend, car idles at 3.4bar and when i bomb it. 5.1bar :shock:
this cant be right (according to the manual) guessing that the injectors ( low indapendance - explains the drop transistor) cant cope, will be doing a total rebuild once i have everything (buying monthly bit here n there) but want to drive her till that day....

guys. fpr problem or not? organised another origional one, hopefully get it soon, mine was also knocked in ( previous owner :x ) gona try it and if no luck, who will sponser the bonfire? (+- 50c matches, tank still has gas :twisted: )

Posted: Mon Nov 02, 2009 11:49 am
by Speed breeder
fuel pressure gauges normally with fuel pressure regulators are mechanical... ie need to run a fuel line to them to see pressure, thus the gauge will be in the engine bay

where as electrical ones will have the gauge inside the car cockpit with only a signal wire running from the bay and sender

you can hook up a mechanical pressure gauge inside the cockpit as well, but if you have a leak, petrol all over... not safe...

you want to see the pressure when you are driving...when fueling problems occur

Posted: Mon Nov 02, 2009 12:49 pm
by Andrew.200SX
The latest that I have noticed is , that the original owner has a clamp on the return fuel pipe , and when my car starts to miss ( which is now getting very bad - .3 bar boost and bang ) you cannot accelerate past it , but when I remove the vacuum pipe from the FPR , it can. The miss is still there , but I can rev through it.

I am busy doing the timing chain and service on my Grand Voyager this week, so next week , I will start with the SX.

First up - Walbro Fuel Pump !! and then who knows !

Posted: Mon Nov 02, 2009 5:30 pm
by antman
Hi, seems to me you are over fueling, by taking off the vac pipe off the the fpr you are reducing fuel pressure under boost which when you did this it was better. Have you tried another fpr? I am running at .9bar boost with 2.9 bar fuel pressure and about 3.5bar under boost on std injectors.

Posted: Tue Nov 03, 2009 6:14 am
by Andrew.200SX
As far as I can tell , that would mean that it is overfuelling , but the car is definitely running lean. You can see it on the plugs and since I got the car , everytime I washed it I had to scrub the black crap off the bumper above the tailpipe , since the miss there is nothing. There was allways black smoke under hard driving , now .. nothing.

Where can I get an original new fpr or a second hand one that whoever it belongs to knows it is working ?

Posted: Tue Nov 03, 2009 6:58 am
by antman
Hi, I see you are in the Cape region...pity as I am on the west rand jhb, my sx is standing waiting for the rb to arrive, you would have been welcome to come over and trial and error any part you want.
If I was you get a fuel press gauge and see what pressure you are running, get a cheap autogauge one, the mechanical one and if you are worried about fitting it in the car rig it temporarily outside by the wipers so that you can see while you drive. Monitor the readings in and out of boost. You need to know this. Remove any restricting clamp on the return fuel line that I think you mentioned on the return, this is a back yard method to up fuel pressure.
Once the fuel press is in spec get your injectors checked for flow etc. clean out fuel rails and pipes as well as the return pipe to the tank.
If all this is good then move on the the next set of tests.
As said by someone else, coil packs can break down when hot so try to do your resistance tests when cold and then when hot (when motor starts to miss)
Hope you come right here.
Tony

Posted: Tue Nov 03, 2009 7:55 am
by Speed breeder
good advice there tony...sums it up nicely.
also make sure filters are replaced at the same time (use the bigger skyline filter if you can)

Posted: Tue Nov 03, 2009 8:05 am
by Andrew.200SX
Thanks guys. I appreciate it. The car was cocking me around only when hot , now it is constant.

I will get stuck into her on Monday.

Thanks again

fpr

Posted: Thu Nov 05, 2009 9:13 pm
by acemine
with the vacuum hose disconnected my fuel pressure stays at 3.8bar, think its abit high, not to sure wat the hell the previous owner has done, my fuel pump feeds from the bottom of the tank??? the 2 outlets on the top of the tank, one is closed and the other is the return..... im assuming with the standard pump out youd most probebly run out of fuel with a half tank still available lol.... wondering if its causing high pressure? hopefully will get the part n sum spare time to work on the car soon.....

Posted: Fri Nov 06, 2009 6:08 am
by antman
Hi ACEMINE, It seems that the previous owner has upped the fuel pressure by physically increasing the spring tension of the FPR. This is done by physically forcing the central metal can part of the FPR in increasing the spring which results in increased fuel pressure. This should be done in conjunction with a fuel pressure gauge and in small amounts of adjustment. Once you bang it in too far you cannot reverse it and you end up with a piece of scrap. I have a spare modded FPR which you are welcome to try out.

Tony
082 8766837