Normal?

KMT

Registered User
I put a test gauge on the fuel rail today (stock 1990 w/auto trans), after removing the Schrader valve...engine had been shut down 10 minutes earlier and there was still pressure and a bit of raw fuel to deal with - normal.

When I put the test gauge on the open fitting, it only took a moment for pressure to start showing on the gauge. It crept up to at least 2 psi before I moved on with testing and started the engine. I don't think this is normal....?
 
If im right in what your saying, you ran the engine to operating temp, let it sit about 10min then started with the fuel rail. So then there is the possibility that you have pressure between the pump and a nasty fuel filter that still bled out.
or where you at an incline/decline for centrifugal force.
Might have bumped the key.
Heat might have caused expansion.
Vapor might have caused expansion.
Just all possibilities but not really sure what to tell ya.
 
Didn't touch the key...no incline...

>Heat might have caused expansion

I'm liking that one, thanks.
 
I'd just check your vent in the tank to make sure it's venting. Run the car, then pull the gas cap off. There shouldn't be a vacume.

The pressure could come from heat expanding the fuel in the tank and creating pressure, but it shouldn't do that as it should vent any excess pressure.
 
I'd just check your vent in the tank to make sure it's venting. Run the car, then pull the gas cap off. There shouldn't be a vacume.

The pressure could come from heat expanding the fuel in the tank and creating pressure, but it shouldn't do that as it should vent any excess pressure.

No, the fuel rail is part of a closed system with the fuel pump on one end and a pressure regulator on the other. Heat and expansion will create pressure with no outside influences. What he observed is normal if the engine was warm.
 
>normal if the engine was warm.

Engine was warm - I was worried that maybe it signaled something awry w/the FPR, but now I'm all for calling it normal, thanks.
 
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