FUEL SMELL HUNT: under throttle, have checked under manifold
02-06-06, 07:26 PM
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FUEL SMELL HUNT: under throttle, have checked under manifold
Ok, i'm still hunting a couple of issues with my rebuild... i know everyone is tired of fuel smell threads but i have searched and am needing some input.
my braking isn't as good as it has been (i.e. pedal feel and response is down) and my fuel smell only comes under throttle load and boost (beyond about 4psi). it is definitely unburned fuel, and comes from the driver's side first and foremost then fades to nothing. no smell under bonnet even IMMEDIATELY after it was present in the cabin.
i have been under the manifold with cotton buds, swabbed and smelt everything and nothing has a fuel tinge at all.
have pressurized the fuel system and found no smell or leaks anywhere.
have just rebuilt the engine and the injectors were never removed from the rails (obviously i had to take the primaries out, but the secondaries never moved) so i don't suspect o-rings.
basically, since it comes through drivers side... i'm suspecting the brake booster line... i didn't do this in the hose job so the check valve is still there but it isn't looking too fresh. i know this part fails under heat (hence the US recall, JDM still sits above the turbos) and i am running without heat-shields until i get all the problems out of the way... i could potentially have burnt the check valve out.
i've taken the (rather perished) hose out, and can only blow through the valve one way... so now we get to my question. a failed check valve; would it need to get to a certain amount of pressure to have blow-back? or would it just flow both ways even under low pressure?
my braking isn't as good as it has been (i.e. pedal feel and response is down) and my fuel smell only comes under throttle load and boost (beyond about 4psi). it is definitely unburned fuel, and comes from the driver's side first and foremost then fades to nothing. no smell under bonnet even IMMEDIATELY after it was present in the cabin.
i have been under the manifold with cotton buds, swabbed and smelt everything and nothing has a fuel tinge at all.
have pressurized the fuel system and found no smell or leaks anywhere.
have just rebuilt the engine and the injectors were never removed from the rails (obviously i had to take the primaries out, but the secondaries never moved) so i don't suspect o-rings.
basically, since it comes through drivers side... i'm suspecting the brake booster line... i didn't do this in the hose job so the check valve is still there but it isn't looking too fresh. i know this part fails under heat (hence the US recall, JDM still sits above the turbos) and i am running without heat-shields until i get all the problems out of the way... i could potentially have burnt the check valve out.
i've taken the (rather perished) hose out, and can only blow through the valve one way... so now we get to my question. a failed check valve; would it need to get to a certain amount of pressure to have blow-back? or would it just flow both ways even under low pressure?
02-06-06, 09:12 PM
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there is one aluminum check valve near the driver's side front of the UIM that you want to check or just replace to rule it out. i forget exactly what it does, but i remember it being fuel related. possibly vacuum to the return or something. memory is slipping on me...
Here are a couple of thread for ya.
https://www.rx7club.com/forum/showth...hreadid=113638
https://www.rx7club.com/showthread.p...ll+under+boost
Here are a couple of thread for ya.
https://www.rx7club.com/forum/showth...hreadid=113638
https://www.rx7club.com/showthread.p...ll+under+boost
02-06-06, 09:13 PM
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Just get the brake line recall hoses - the kit should be way cheap and that will take care of that.
Dale
Dale
02-06-06, 09:23 PM
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i'm JDM so my brake booster line runs straight from the booster to the UIM (about 7 inches) as i don't have the hardline along the firewall... thats what makes me think i've had heat kill that line.
kit here is US$30, and the check valve has to stay directly above the turbos...
kit here is US$30, and the check valve has to stay directly above the turbos...
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