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Sat Jan 16, 2010 7:33 am

What is your choice for a FPTESTER? What is the size of the adapter that goes into the test hole? Harbor Freight tester any good? Thanks

Sat Jan 16, 2010 7:37 am

I fabbed up a gauge I bought in the plumbing section of Home Depot; pressure gauge goes up to about 100 psi so the resolution is fair but still useful. Connect up the required hose barbs and adapters and a length of fuel line and clamps onto the port on the fuel rail (cold start port on a D-jet). Total cost about $18. For Vanagons, a tee may be required to hook it up.

Sat Jan 16, 2010 7:53 am

I use this one myself because it is cheap and has better resolution, but a liquid filled one would be a step up...

http://www.summitracing.com/parts/VDO-153008/

Sat Jan 16, 2010 12:38 pm

On the cheap the plain old plumbing store gauge works fine (for occasional use) with a caveat: it will probably be off 2 or 3 psi in one direction or the other. But the error will also probably be the same amount at the high and low pressures you need to measure. So if you test with vacuum applied to the FPR and it reads 31psi, when you're looking for 29, don't judge your FPR bad just yet. Remove the vacuum and it'll probably read 38 instead of 36. That's a pretty good sign that the gauge has a 2psi error and your FPR is actually OK.

But, nowadays, the FLAPS and HF carry tools that are more accurate than that and just a few dollars more. If you value your time, the extra effort it takes to get the fittings together at the plumbing dept. and assemble your own might be a fair trade for buying a ready-made gauge, and the ready-made is likely to be a bit more accurate than your typical water gauge. As always, it's time or money, choose according to which is more dear to you.

Sat Jan 16, 2010 1:41 pm

The "adapter" is just a piece of fuel line, the same size as is used in the engine bay, 7mm injector hose. It is simply clamped onto the "T" test hole connector once you remove the bolt plug and small washer (don't lose it) The washers are available at VW for pennies each.

Sun Jan 17, 2010 12:54 pm

I was able to buy a nice high quality glycerine filled gauge from my local plumbing jobber for $8 a few years back. Should last a lifetime and occasional use.

Mon May 21, 2012 7:14 pm

Sorry for reviving the good old thread, but I was wondering if any of you guys that have chosen the 'el cheapo' way have encountered the following. I got a 0-100psi gauge from a hardware store nearby and followed instructions to make the pressure tester. Rigged appropriately in the T rail, and when I started up the engine the gauge needle went over the 100psi mark. turned off immediately and the needle slowly crawls back to 0psi. Can you get more than 100psi in the system with a blocked FPR? No fuel is coming out anywhere in the gauge, so my guess is that the FPR is not sealing, and probably not opening appropriately at idle. What should I do next before replacing the FPR?

I forgot to tell you guys, I got a 1984 1.9L Digijet with a brand spanking new set of FI lines, fuel filter, completeley new exhaust system and O2 sensor and the VC 8385 OBD Digitool installed.

Mon May 21, 2012 8:47 pm

Either a bad regulator or a clogged fuel return.

Tue May 22, 2012 3:34 am

My press guage i carry is made up of a 3-$4 round tire guage. Unscrew the stem cover, twist on a scrap sect of fi hose, clamp,add another clamp for the 'T' and works fine,slip clamp up on hose to keep together for future use.

Tue May 22, 2012 8:08 am

You are correct, Wildthings. Today I checked the source of the leakdown as per Tencentlife suggestions on other threads (building pressure in the FI system, then pinching supply and return lines), and I could pinpoint the regulator as the source of the leak. Moreover, I cleaned and carefully blow air through the return line and is totally unobstructed. So the FPR is not sealing, and as you suggested it might not be doing its job regulating FP either.

I will be changing the FPR soon (ordered today from BD) and I really hope I get rid of the overly rich issue is hunting me since I bought it a few months ago. It was running rich when I bought it, but progressively started to get richer, and the pump was screaming due to apparent cavitation, I guess because of the gradually higher pressure building up in the system.

Mon Jun 04, 2012 12:09 pm

So, the FI pressure now is where it should be with the new FPR! It puurrrrs so nice with the right amount of gas and a new exhaust system! Thanks for your help guys!

Wed Aug 29, 2012 3:53 pm

Randy in Maine wrote: I use this one myself because it is cheap and has better resolution, but a liquid filled one would be a step up...

http://www.summitracing.com/parts/VDO-153008/

For those of you who use a good fuel pressure gauge with the 1/8 male connector on the back ( like the summit racing one in the above link), how do you connect the fuel hose to it? Directly on the threads with a good clamp ok? I can find a 1/8 female barb for the life of me!

I am justing using it as a tester, not a permenent install... But I dont want to get around back to see its poped off the hose and fuel sprayed everywhere....

Thu Aug 30, 2012 7:05 am

morymob wrote: My press guage i carry is made up of a 3-$4 round tire guage. Unscrew the stem cover, twist on a scrap sect of fi hose, clamp,add another clamp for the 'T' and works fine,slip clamp up on hose to keep together for future use.

Pictures of said $3 Fuel pressure gauge. http://dubnyc.tumblr.com

Boostd wrote: Randy in Maine wrote: I use this one myself because it is cheap and has better resolution, but a liquid filled one would be a step up...

http://www.summitracing.com/parts/VDO-153008/

For those of you who use a good fuel pressure gauge with the 1/8 male connector on the back ( like the summit racing one in the above link), how do you connect the fuel hose to it? Directly on the threads with a good clamp ok? I can find a 1/8 female barb for the life of me!

I am justing using it as a tester, not a permenent install... But I dont want to get around back to see its poped off the hose and fuel sprayed everywhere....

A clamp is usually what goes on barbed connections.

http://www.thesamba.com/vw//forum/viewtopic.php?t=422307&highlight=

Thu Aug 30, 2012 7:58 am

What I am wondering is if I can clamp a hose directly onto the 1/8 threads on the back of the gauge, or If I need to find a 1/8 barb connector ( much more secure). Gonna go check some more auto parts stores for a 1/8 female barb, but if im in a pinch I might just clamp the hose directly onto the threads on the gauge.

Thu Aug 30, 2012 9:06 am

Boostd wrote: What I am wondering is if I can clamp a hose directly onto the 1/8 threads on the back of the gauge,

I've done that witout a problem, clamped hose over threads is quite secure at the pressures you'll see.