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Tue Feb 09, 2016 10:55 am

I am looking for a fuel pressure gauge. Not sure what I should look for to make sure it fits where I need to attach it.

I believe it goes on the removable screw fitting on the 4 way fuel line fitting laying on the case next to the distributor.

I'm guessing that once again whatever I have is completely different than a normal modern car has and most gauges would need some sort of fix to make it work. Looking for a low cost solution with minimal mods. Probably will need this once or twice in my remaining van lifetime.

Tried to search this but just kept getting blank results.

Tue Feb 09, 2016 11:02 am

This search has some info that may help you.

http://www.thesamba.com/vw/forum/search.php?search...=titleonly

Tue Feb 09, 2016 2:43 pm

Yes, remove that tiny screw..... DON'T LOSE IT OR THE SEALING RING!!!!!

Put a hose on the fitting and clamp it on,
Fasten hose to gauge,
Start engine and read pressures.

Easy Peasy!!!

Dave

Tue Feb 09, 2016 2:51 pm

djkeev wrote: .

Easy Peasy!!!

Dave

Yep. The one I borrowed from the FLAPS came with half a dozen different adaptors. It was no problem at all.

Just remember to GENTLY release the pressure before just yanking the gage off of that fitting. The gasoline volcano that I was treated to was unwelcome to say the least.

Wed Nov 20, 2019 4:27 pm

I need to test my fuel pressure also and found this thread by searching. My van won't run long enough to get me to the FLAPS so borrowing that tool (great suggestion, by the way) might be out. I did price a set at Harbor Freight yesterday but it appears that all the connection fittings are clamp on or press on, no threaded ones to fit our fuel T. Hmmm, is that safe?

Removed the little bolt to check the size and checked against my stash of bike parts, figuring what I need is a bicycle brake barrel adjuster to use as the thread-in piece to clamp a hose onto. Knew immediately that the size would be a problem since most adjusters are 6mm diameter by 1mm threading. Too big. I also remembered that old French 10-speeds used very small adjusting barrels so it was off to the co-op to check out the scrounge boxes. Bless their hearts, I found two Huret Allvit rear derailleurs (who among you remembers those?) with adjusters intact and scavenged them. I'm working in a gravel driveway and I will drop one of them. That's the law.

Anyway, now that I have the piece I can buy a gauge and do my testing, fully aware that my "Goddam, I'm freakin' brilliant" feeling might well come crashing down on me.

Below: Typical adjuster on top, with screw from my bin that matches the threading on the T bolt that I used to search for the smaller barrel.

This should pass enough fuel for a pressure test, right?

Wed Nov 20, 2019 4:32 pm

The 5/16 hose hooked to your gauge will fit on the outside of the tee, no need to come up with some weird adapter setup.

Wed Nov 20, 2019 4:37 pm

campism wrote: ...I did price a set at Harbor Freight yesterday but it appears that all the connection fittings are clamp on or press on, no threaded ones to fit our fuel T. Hmmm, is that safe?...

I have tested mine by just clamping fuel line on that tee - it's less than 35 psi. Anyway. clamps are what are holding the lines on throughout the system.

In a pinch I have used an oil pressure gauge and it worked just fine though now I have that HF kit (probably the one you looked at):

https://www.harborfreight.com/Fuel-Injection-Pump-Tester-62623.html

Wed Nov 20, 2019 4:37 pm

It might work, if it fits, and adapts to your gauge and is able to seal. And the center hole size doesn't matter, you're testing pressure, not flow (look up Boyle's Law). But the threaded hole in the 4-way tee is just to admit a bolt to seal it off when you don't need it, the test branch of the 4-way tee is barbed like the others so a piece of fuel hose can be slipped over it and clamped for the test.

Wed Nov 20, 2019 8:37 pm

I'll try and report back. Thanks!

Sat Nov 30, 2019 11:32 am

Bought this today, the HF one posted above, so I'll try it out when the rain stops.

Mon Dec 02, 2019 2:02 pm

Fuel pressure checks okay, although I still could not start the van so could not test with the engine running. Switching the key to On and priming the fuel pump gave me about 32 PSI and that is close to what the Bentley recommends. I used the gauge with the barb fitting (bottom right) and the thicker of the two short hose sections along with the two clamps, what the HF gauge instructions recommend as the "VW" setup.

Problem must lie elsewhere so will proceed with troubleshooting as time and weather permit, and assume that fuel pressure is not the issue here.

Mon Dec 02, 2019 2:43 pm

Maybe it is time for you to tell us what your problem is. No start? Lack of power? Stalling?

Mon Dec 02, 2019 5:36 pm

Mentioned elsewhere. My post in this thread was specifically about fuel pressure testing, but I'll fill you in.

Historically, van ran fine. Once about every twenty cold starts it would get up to temp and stumble, then not rev above about 3,000 RPM. I'd shut off while rolling and restart and it would run fine thereafter. Recently after prolonged parking with only occasional startups, it began doing it every start. Started fine, idled smoothly and got up to temp, then stumbled and not rev as historically, but now the typical shutdown and restart did not cure it. Then, when I recently went to move it into the garage for some serious troubleshooting it would not start. Cranks, tries to fire but stumbles and dies within a couple of seconds. Every attempt.

Hence the fuel pressure test, results of which appear to be good. Now on to the rest of the troubleshooting; grounds, vacuum leaks, etc.

Thanks for your interest and help.

FYI: third owner, stock '87 2.1L WBX with manual trans, 93xxx miles.