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Fuel pressure regulator
ancientbugger - September 1st, 2012 at 03:22 PM

Would anyone on here that's familiar with the factory FI system be able to tell me whether the standard FPR can be changed to an adjustable aftermarket type? I'm asking as I reckon trying to get hold of an original type may prove difficult. Plus would a failed FPR result in billowing black smoke and saturated plugs? (I have googled already , I just want knowledgeable VW folks input)


ian.mezz - September 1st, 2012 at 03:38 PM

whats it look like, it could be the same as another make of cars.?/
Eg , VK commodore , Volvo etc.


ancientbugger - September 1st, 2012 at 03:58 PM

Trying to post a pic but failing dismally but it's a standard looking Bosch regulator with one vacuum tube plus a fuel inlet and outlet


vwo60 - September 1st, 2012 at 05:53 PM

If you have a part number you can check on the samba, this could be the correct one, its new.
http://www.thesamba.com/vw/classifieds/detail.php?id=1315582 


ancientbugger - September 2nd, 2012 at 11:01 AM

That is the right one Shane, but first I thought that maybe the diaphragm inside had split and so pure fuel was being pushed via the vacuum tube into the plenum but on checking this morning by turning on the engine and pulling off the tube the revs went up and no fuel came out, so now I'm thinking would a stuffed FPR be allowing too much pressure. To allow me to check the pump independently of turning on the engine I've wired it up to a switch rather than to the double relay but now I can start the engine even with the pump switched off but when I switch the pump on thick black smoke is produced so could the FPR be somehow blocked open, also with the pump off but engine running if I try to rev up it will cut out. Please excuse my ignorance but I'm really over FI and the longer this goes on the more a carburettor looks attractive.!


matberry - September 2nd, 2012 at 01:46 PM

Yes an adjustable reg will do, but it will need to be an EFI specific, and then set to suit your system. Type 3 is 28 psi, yours maybe 32, I'd need to check. I have the gear to accurately set, and yes, over pressure can cause major smoke


ian.mezz - September 2nd, 2012 at 02:37 PM

Quote:
Originally posted by ancientbugger
That is the right one Shane, but first I thought that maybe the diaphragm inside had split and so pure fuel was being pushed via the vacuum tube into the plenum but on checking this morning by turning on the engine and pulling off the tube the revs went up and no fuel came out, so now I'm thinking would a stuffed FPR be allowing too much pressure. To allow me to check the pump independently of turning on the engine I've wired it up to a switch rather than to the double relay but now I can start the engine even with the pump switched off but when I switch the pump on thick black smoke is produced so could the FPR be somehow blocked open, also with the pump off but engine running if I try to rev up it will cut out. Please excuse my ignorance but I'm really over FI and the longer this goes on the more a carburettor looks attractive.!

just need to check fuel presure with a in line gauge ,
when you pull vacuum line off it will rev up a bit as gives it more fuel. shouldnt be able to start any EFI car with no fuel pump.:crazy:


ancientbugger - September 2nd, 2012 at 04:35 PM

So to clarify, the engine starts but will only idle with pump switched off (I know it shouldn't but it does), a touch on the throttle it stops, so would the engine be sucking enough to get fuel through? It must be as the pump is off, would a stuffed FPR -allowing fuel through too easily - let this happen? If the pump is switched on it belches black smoke, again if the FPR is allowing too much fuel would this be the scenario?


matberry - September 2nd, 2012 at 05:30 PM

Thjere's more to it than just the reg IMO but fuel pressure is the easiest thing to check and always the first thing to do.


ancientbugger - September 3rd, 2012 at 11:09 AM

As far as I can find (via google) the pressure should be 28psi