OK, I just installed a fuel pressure gauge on my car. There is only one problem (I think). When I turn the key to KOEO, (key on engine off) the fuel pump primes, of course, for about two seconds, and the pressure goes to 10 PSI. But once the fuel pump stops priming, the pressure drops to 0. Is this normal or bad? I know that if a car runs for a while and then you shut it off it should hold the pressure. But I am unsure about my situation. Anyone know?

 

IIRC there is a checkball in the fuel pump thats supposed to stop the fuel from draining back to the tank. It doesnt always seem to work. As long as it maintains 10-12 psi across the engines operating range then theres nothing to worry about.

 

Alright, good. Thanks for the info. I have yet to start the car since it's in the garage and blocked by another car but when I saw the pressure drop I got worried. Thanks again.

 

which guage did you get and how hard are they to install?

 

perfectly normal . . .the iniital reading you are seeing is the fuel pump priming the TBI . . .once primed, after two secs, the pressure recedes -- but, once it starts up the pressure should stay right around 11psi

--thraxxx the easiest gauge to install is the actron TBI pressure gauge. You can even leave the fitting installed. IIRC all you need is a 3/4 and 5/8 wrench.
http://www.actron.com/product_detail.php?pid=16175
found one at the local A-zone for about fifty bucks

 

ThraxXx, there are two options for installing a fuel pressure gauge on a TBI car. One is what adambros suggested (which is probably also the best way since it screws in between the rubber and metal fuel lines) and the other is what I did.

I am using Summit Racing part numbers SUM-G1710 (fuel pressure gauge fitting, 3/8" tee, 1/8 female NPT) and SUM-800130 (0-30 PSI Summit mechanical fuel pressure gauge, liquid-filled, 1/8 male NPT). First thing you do is relieve fuel pressure by taking the gas cap off and letting it sit for a while. Then all you have to do is cut into the rubber inlet fuel line in the engine compartment (the bigger 3/8 line) and install the tee. Then clamp it down with hose clamps and then put some teflon tape on the fuel pressure gauge and then screw it into the tee, tight! That's all you have to do, pretty much. If you do a search under "TBI fuel pressure gauge" you will find tons of info on installing a FPG either way you want to do it. Neither way is hard at all it just depends on how much $ you want to drop on one.

P.S. You only need a gauge that goes to 15 PSI, FYI.

 

Hmm... ok I think I am gonna go that route. I need to see why my car runs so rich and the fuel preasure guage will probably be my best aproach.

Thanks for the help

 

If you need any more info on installing one just let me know.

 

Here's where I put my fuel pressure gauge.

 

I put mine in the exact same spot. That's the perfect place for it.

 

For that kit can you install it in between the hard line and the soft line in the engione bay or do you have to put in at the fuel filter.

 

heres where the actron kit installs. its that brass fitting in the lower left pic.

 

Cool than thats the kit I want.

 

I have seen fuel pressure adapters listed in a Summit catalog.
Made by Earls, IIRC.
Just have to know which size fittings they are on the fuel lines.
What's AN and NPT?