Guide To Hooking up Fuel Pressure Tester on 1st Gen

Can't believe what a pain this is! The info is online but it's pretty scattered and I found that the actual process is much trickier than it seems like it should be so here's a quick guide. This is on a 2000 w/ 3.4L 5VZ-FE and I got the correct fitting from this thread https://www.tacomaworld.com/threads/3-4l-fuel-issue.452218/page-2

These trucks have no test port for fuel pressure. You basically have two options - crack the double flare fitting on the driver's side or use a test fitting in place of one of the banjo bolts on the fuel rail. The service procedure is to use the banjo bolt and this is what I did, opening that flare fitting is risky as it may not seal correctly and it also requires making up a pretty weird tee fitting anyway.

You will need a pressure test kit (I did an autozone rental tool) AND a special banjo fitting. This is the fitting I got "
Fuel Pressure Gauge Adapter Banjo Bolt Fitting M12 x 1.25" 1/8-27 NPT Female to Male 90 Degree Elbow"
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$10 Fuel Pressure Gauge Adapter Banjo Bolt Fitting M12 x 1.25" 1/8-27 NPT Female to Male 90 Degree Elbow Compatible with Honda Civic DELSOL Prelude NSX Acura Integra

https://www.amazon.com/dp/B07HY22882?ref=ppx_yo2ov_dt_b_product_details

The important part is the M12 x 1.25" which is the banjo fitting and then you need a pipe thread on the end to install a 90-degree elbow. This Amazon fitting was junk and I don't recommend it, but it should work if you can't find a better option. I broke mine - more on that in a sec. Next time I would definitely try the Russel 640700 mentioned in that first link it looks much better.

You may also need some fittings to adapt your pipe thread to something in your test kit. You will be able to get these at any decent hardware store. I had to get a 1/8NPT x 1/4" NPT coupler with a 1/8" close nipple and a 1/4"NPT x 1/4" Flare adapter.

Installation is a little tricky and has to be done in a pretty specific order that might vary depending on what fittings are in your test kit.

My first problem was that the hole in this amazon banjo fitting is tiny. This shouldn't be an issue checking fuel pressure at idle but I thought it might cause problems with more thorough checks so I drilled it out to the same size as the factory banjo bolt and countersunk the holes like factory bolt.




This was a mistake. This cheap brass fitting is too weak to drill out so much:



If I was doing it again I would probably still drill it out but not quite as large as the factory bolt.

Luckily I have some nice tools in the shop so I was able to adapt one of the fittings in my test kit to make a replacement.



Anyway, moving on.

You gotta keep in mind the next thing in line after this banjo bolt is your fuel injectors so cleanliness is absolutely critical. After drilling I deburred with a countersink and then cleaned the inside of the bore with a brass brush and then sprayed everything with carb cleaner.

Even if you're not modifying anything you need to spray all these fittings out with carb cleaner before using them.

The banjo bolt and any flare fittings don't need pipe tape but NPT (pipe) fittings need a fuel rated (yellow) pipe tape. BE VERY CAREFUL NOT TO GET ANY INSIDE THE FITTINGS - it will go right into your injectors. I start the tape about a thread back from the end. Use plenty of tape, 2-3 full turns.



Once you've figured out how to get from the banjo bolt to whatever pressure tester you have you're on to assembly.

First up take out at least the top four bolts from the plastic timing bolt cover. The FSM says to remove it but you can just pull those top bolts and scoot the clamp on the coolant hose back and it gives you plenty of room to push to plastic cover out of your way as you work.

Now crack the banjo bolt on the driver's side of the front of your fuel rail. You could figure out what relay to pull to release fuel pressure but there's really no need, just put a rag under there and keep your face back as you loosen the bolt so you don't get sprayed.

Take the banjo bolt out completely and replace it with your test bolt, with nothing else installed on it yet.

I found it's easiest to also crack the banjo bolt on the passenger side so that you can swing the fuel line up when putting the new bolt and crush washers on.



Your test kit and/or test fitting may have new copper crush washers, that's ideal. If you have to re-use the old ones anneal them by heating red hot and letting them cool. Make sure there's a crush washer on inside and outside of the banjo fitting:



Get your banjo bolt threaded in almost all the way but still only finger tight. Then install your 90-degree pipe fitting, with yellow PTFE tape.

It's tight in there so instead of trying to spin the pipe fitting into the end of the banjo bolt to start the threads just hold the pipe fitting up against the end of the banjo bolt and use a finger to UNSCREW the banjo bolt into it - this will start the threads on the pipe fitting:



Now you need to tighten your banjo bolt and that 90-degree pipe adapter. Hold the banjo bolt with a second wrench when you tighten the 90-degree fitting so you're not loading it up too much. In the end both need to be pretty tight and - IMPORTANT - the adapter needs to be facing upright. Not tight enough and it will leak (or spray) gasoline but if you crank too hard you do risk breaking this crappy china brass banjo bolt like I did the first time.

Because it matters how they are clocked you can't do one and then the other you need to kind of do them at the same time.

Anyway, get them both good and tight and if you can try to end up with the 90-degree fitting pointed a little to the left, like at 10-o'clock. This will give you some wiggle room to tighten if you do have a leak.

Now it should look like this:


Now you can install whatever parts you needed to get to your pressure tester. For me that was this:



Make sure all the spilled gas has evaporated then install the pressure tester and check for leaks. Take your time you do not want to spray fuel everywhere if you forgot to tighten something. Best to have a helper for this and definitely have a fire extinguisher on hand.

First just crank it over a few times without letting it start and make sure you're not spraying fuel. Then crank till it fires and immediately shut off and look for drips. If needed tighten things up and keep checking.

No leaks and you're done. There's plenty of threads about what the correct pressure should be and how to troubleshoot pressure issues so I won't get into that.

 

This is the one I found....is it any better....

$15 RUSSELL/EDEL 640700 Fuel Pressure Take Off Banjo Belt

https://www.amazon.com/gp/product/B000CPJI8I?smid=A2L97JA8DAGJXC




It would be a bad day.....if it breaks off inside the fuel rail while squashing that crush washer down.....

 

I think that one is probably better. At least the hole is the correct size. It's actually not that bad if it breaks, it's not a tapered thread so the broken bit comes out easily. Not great though...

 

Yeah I'm still waiting for someone to come up with a pressure transducer / electronic gauge combo....

so you don't have to run beside the truck while going down the highway....

when a pump starts to fail....it doesn't necessarily show until a continued prolonged high draw....


And I'm not real thrilled about running a braided hose thru the firewall...

 

I closed the hood with just the safety latch and ran the gauge up to the windshield with painter's tape. It's ... a solution I guess

 

First, thank you @blackpiglit for posting that.
Second, same thank you to @O'Silver_Taco for pointing out what could be trouble if the fitting breaks in the rail when installing.
And now the off the wall portion of this post.
Is there a machinist or metallurgist in Tacomaworld that could tell me that if that fitting @blackpiglit bought from Amazon was made from 642 bronze would alleviate the fear that O'Silver brought up?
I know, I know. I like to over think things sometimes.

 

Same here.....I really appreciate those that go thru and take the time to document and post this stuff..

Sorry I'm the one who's usually the devil's advocaat....
.....the 'not so quick buddy'......

 

Yes definitely would. Tensile strength of bronze is much higher than brass, especially low quality chinese brass of unknown composition. But I think it would have been fine if I hadn't drilled it out quite as much as I did.

 

You know the pressure gauge 2rz/3rz tap that LC engineering sells...taps into the fuel regulator on the far side of the rail so as not to impede the flow and simplicity to install ...but that may affect the regulator function....and may not be meant to leave in for extended periods....

an upstream one may not have an accurate psi for a fast flow stream across it...
....the venturi effect...

just a thought...

 

@Indyteecee pointed me to a thread I hadn't seen where someone else also broke off their first banjo bolt:
https://www.tacomaworld.com/threads/3-4l-fuel-issue.452218/page-2

According to that guy the

$15 Russell 640700 Fuel Pressure Take Off Banjo Belt

Russell 640700 is the fitting to buy