Vacuum re-route for FPR-Plenum
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Vacuum re-route for FPR-Plenum
Ive made some changes on my engine and I put the vacuum line from the FPR straight up to the vacuum port on the back of the Plenum.Has anyone done it this way?Any problems?The old line was a 2 piece line that connected to a AIR vacuum port at the front of the engine at the a/c area.I took that stuff out.
Also,when I unplug the vacuum line there,I can smell gas inside of it and at the FPR,but its not wet,just the "fume" smell.I never noticed this before in the past and Im wondering if thats normal?The FPR is just a few years old,and was a brand new GM unit.Should you be able to smell gas fumes from the vacuum line of the FPR if theres no leaks?
Im just checking around and making sure everythings OK.Its getting late now and dark out so I will wait til tomorrow to start the car with the FPR line unplugged and see if any gas spits out or leaks there.
:cheers:
Also,when I unplug the vacuum line there,I can smell gas inside of it and at the FPR,but its not wet,just the "fume" smell.I never noticed this before in the past and Im wondering if thats normal?The FPR is just a few years old,and was a brand new GM unit.Should you be able to smell gas fumes from the vacuum line of the FPR if theres no leaks?
Im just checking around and making sure everythings OK.Its getting late now and dark out so I will wait til tomorrow to start the car with the FPR line unplugged and see if any gas spits out or leaks there.
:cheers:
Team Owner
Joined: Dec 2000
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From: SE NY
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Re: Vacuum re-route for FPR-Plenum (Bill's86Coupe)
My '88 pulls FRP vacuum from the rear of teh plenum, you should be fine.
If you are getting a heavy gasoline smell I suspect the FRP diaphram is leaking.
If you are getting a heavy gasoline smell I suspect the FRP diaphram is leaking.
Drifting
Joined: Jan 2002
Posts: 1,606
Likes: 1
From: Las Cruces NM
Re: Vacuum re-route for FPR-Plenum (jmrl98)
I'll go head and agree with the other guys about your diaphram leaking.
My '86 had the fpr vacuum line go strait to the plenum and it had no problems.
Chris
My '86 had the fpr vacuum line go strait to the plenum and it had no problems.
Chris
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Re: Vacuum re-route for FPR-Plenum (okinawa86vette)
Thanks for all the replies everyone.Later today I will hook up the FP gauge and watch the pressure and unplug the vac line and see if any gas spits out.
But I wanted to know if anyone knew if you should be able to smell gas fumes from the vacuum line or not when you take it off?
I never thouight to check it before and this was the first time and thats when I noticed.Im hoping the FPR isnt screwed,because I really dont want to take the bastich apart again.I just finished installing new intake gaksets and new TPI gaskets and etc.Its not a hard job,just with a bad back it takes me forever to do the job here and there from start to finish.Ugh.
:banghead:
But I wanted to know if anyone knew if you should be able to smell gas fumes from the vacuum line or not when you take it off?
I never thouight to check it before and this was the first time and thats when I noticed.Im hoping the FPR isnt screwed,because I really dont want to take the bastich apart again.I just finished installing new intake gaksets and new TPI gaskets and etc.Its not a hard job,just with a bad back it takes me forever to do the job here and there from start to finish.Ugh.
:banghead:
Drifting
Joined: Jan 2002
Posts: 1,606
Likes: 1
From: Las Cruces NM
Re: Vacuum re-route for FPR-Plenum (Bill's86Coupe)
Sorry to be the bearer of bad news, but i nver smelled any gas fumes from the vacuum line or the reg itself. On my '86, I even had the line disconnected to check the pressure diff at idle with and w/o the vacuum. No gas smell like that either.
I fractured a vertabrae in my lower back in a car accident while in Japan when somebody rear ended me at a red light, so I know how it feels to have to take frequent breaks when working on the car, escpecially something you have to lean over, like the intake.
On the bright side, if you haven't done so, now's a good time to put in an adjustable regulator. I know accel and a couple other brands give new diaphrams with their kits.
Chris
I fractured a vertabrae in my lower back in a car accident while in Japan when somebody rear ended me at a red light, so I know how it feels to have to take frequent breaks when working on the car, escpecially something you have to lean over, like the intake.
On the bright side, if you haven't done so, now's a good time to put in an adjustable regulator. I know accel and a couple other brands give new diaphrams with their kits.
Chris
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Re: Vacuum re-route for FPR-Plenum (okinawa86vette)
Hey guys,
Thanks for the replies and the tips.I did the FP test earlier and it passed with flying colors.There was no gas spitting out from the regulator while the car was running and no gas smell at all...even when revving the engine and holding the throttle open at 2000 rpms or so.Cant find a leak anywhere.
The fuel pressure is good,right where it always was and holds with the key off.However.Fast foward 2 hours later or so,im smelling the gas fumes at the FPR again but no gas to be found anywhere.
Have not seen any leaks.Maybe its tiny tiny internal leak that hasnt showed its face yet.
Im going to keep an close eye on it.Im not driving the car anyways,just letting it run and doing checks and tests on things.
If I need another FPR,im kicking myself.I had the adjustable one with the security torx tool and etc but I sold it some time back since my mods didnt warrant a AFPR.Wish i kept it now to do repairs if needed.
Ill let you all know what I find out.Thanks again.
:)
Thanks for the replies and the tips.I did the FP test earlier and it passed with flying colors.There was no gas spitting out from the regulator while the car was running and no gas smell at all...even when revving the engine and holding the throttle open at 2000 rpms or so.Cant find a leak anywhere.
The fuel pressure is good,right where it always was and holds with the key off.However.Fast foward 2 hours later or so,im smelling the gas fumes at the FPR again but no gas to be found anywhere.
Have not seen any leaks.Maybe its tiny tiny internal leak that hasnt showed its face yet.
Im going to keep an close eye on it.Im not driving the car anyways,just letting it run and doing checks and tests on things.
If I need another FPR,im kicking myself.I had the adjustable one with the security torx tool and etc but I sold it some time back since my mods didnt warrant a AFPR.Wish i kept it now to do repairs if needed.
Ill let you all know what I find out.Thanks again.
:)
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