Anybody willing to help me build (tell me what parts I need and where to get them) an inexspensive Fuel Pressure tester for my 2000 4X4 LT Blazer?

I've seen pics of some that forum members have made (Captain Hook's for example) and it doesn't look hard except for knowing what size fittings I need and where to get the hose, gauge, etc.

I have looked on eBay and got myself a little confused on exactly what I need. Some say not for GM Throttle Body Injectors (TBI?) and I'm not sure why unless you need some special connector?

I know there a lot of good people here with a lot Blazer knowledge so...

Anyone willing to help? Thanks in advance.

 

You can get a cheap one from Harbor Freight or borrow one from a auto parts store. Or you could do what I did years ago, get a cheap water pump gauge at a local farm and ranch store ($3 or so). Slip a piece of fuel hose over the end and secure it with a hose clamp. Relieve the pressure on the fuel injection line and remove the valve core from the schrader valve (use the same valve core tool that you would use to remove the valve core from a tire valve). Slip the other end of the hose over the schrader valve and secure it with a hose clamp. Surprisingly I was able to use this for years, I thought that the gas would eat of the gauge right away, but it didn't. Just be carefull you don't spill gas a on a hot engine while doing this.

 

It may be cheaper to buy one...safer too. the test fitting is a -4 SAE/JIC/AN, gauges are usually 1/4" NPT. the only tricky part is depressing the core of the test port, but you could remove it i guess.

I bought mine for $49 and it came with a few adapters for different vehicles.

 

Unless I'm missing something or not understanding something, most of the ones I'm seeing do not work with "GM Throttle Body Injection". Isn't that what my 2000 4X4 V6 4.3L LT Blazer has?

 

Your 2000 4.3L is not throttle body injection. Is it CSFI, (Central Sequential Fuel Injection). Most pressure testers will connect right up. The fitting on the service port is the same as the old R12 refrigerant fittings and an old AC line works well, even has the depressor, but the seal rots out from the fuel.

 

Thank you for that information. The other recommendations make more sense.

Thank you all!

 

I finished making my fuel pressure tester and here is a pic of the finished product.



Good news is it works as designed but the bad news is I'm having a small problem getting it to tighten on the fuel line connection. It leaks enough to let the pressure bleed off and I don't want to over tighten. Maybe some teflon tape on the fuel fitting prior to connecting the hose? The red hose is a used R-12 A/C hose but the seals were replaced and the hose was pressure checked. Gauge (0-100 psi) is new as is the green handled relief valve and it is rated for 600 psi shut off pressure. I also verified it is leaking at the fuel fitting.

Back to the drawing board...

 

Nice job! R12 AC hoses uses the same type fitting, but the hose is not fuel rated. The problem I ran into is the rubber seal is too thick so you have to reef the fitting down to make it stop leaking at the service port. I ended up trimming it down and it works fine except the fuel eats the seal over time. Just need to be aware of it and keep an eye on it. With basically the same stuff you have there, you can make a shut off tool that attaches inline at the fuel filter, for checking maximum pump output pressure and leakdown in the tank.

 

Thanks! Can you explain a little about how you "reef the fitting down"? I'll watch the hose if I can get it to stop leaking. I don't plan on using it a lot and I have access to other "old" hoses when one needs replaced.

Thanks again...

 

Reef it down = might need to use pliers to tighten it