I know this topic has been covered several times before.. believe me I searched the forum but didn't really find anyone with the same strange circumstances.

94 FD, ~15k on rebuild, all new fuel system components/hoses, brand new stock fuel injectors, upgraded supra fuel pump.

Yesterday I start up the FD in the garage and let it idle about 5 min., then I go to back out and notice this huge puddle of gas on the garage floor. I immediately shut it off and investigate. I jack up the front end and start it again -- the gas is dripping down the passenger side of the tranny tunnel. Right away I think either bad FPD or FPR, except these parts are practically brand new. Anyone had one go bad so quickly?

The 2nd odd thing is after yesterday, I cannot reproduce the above results. I have started it up probably 4-5 times since and scoured the UIM area for gas leaks with a flashlight, found nothing. I also jumped the F/P and GND pins @ the diagnostic box several times and saw nothing.

The car was sitting for about a week with a near empty tank when I originally started it yesterday, and I noticed there was quite a rush of air when I removed the gas cap today. Could this be related somehow? I figured that was a normal thing when it got warmer outside, my first FD used to do the very same thing. One more thing I noticed was a slight kink in the PCV tube which I fixed, but I don't think this would be related.

So, I still have yet to tear the UIM off the car but I know I'm going to have to just to check things out. Just wanted to get some input from the forum experts before I dig into it. It just doesn't make any sense to me, but I guess perhaps the FPD or FPR could be bad. I've never heard of one going so quickly though.

thanks,
Mike

 

dang, nothing? Guess I'm on my own with this one. We'll see what I find once I get the UIM off.

Mike

 

Considering the forum has been up and down for the past 12 hours, people probably haven't been able to read your post.

As far as what's going on, it's anyone's guess. A part can be defective from the factory. I would remove the UIM, jumper the fuel pump and look for leaks. If you don't see any, drive the car and just be observant to see if it comes back.

 

Ah, sorry I didn't realize the forum was down for so long.

Thanks for the advice. I'm just going to take my time and go through everything part by part. I will probably replace the FPD & FPR even if they look good, or I may go with an aftermarket FPR. Doesn't SARD make one that bolts to the stock rail & replaces both the FPR/FPD?

I started it up again today and noticed a faint smell of gas, so I started looking around the UIM area with the flashlight again and noticed what appears to be atomized fuel "mist" floating around the harness/regulator/FPD area. So, something is definitely leaking. It appears to be the FPD but I will know more once I remove the UIM.

thanks,
Mike

 

if its a "mist" then i would check the injectors/rail and see if they are secure. i had the same problem on my FC, FB, and troubleshot my friends FD before.... turns out whoever messed with the fuel system prior to my ownership did not tighten down the fuel rails enough on the injectors.

the fd on the other hand is a mystery as it was a 30k mile 1owner car.

it could also be the o-rings/grommets on the injectors

 

Yeah I thought maybe the o-rings or insulators also, I have a spare new set of insulators I'll probably swap in once I get down there.

Mike

 

Noticed something else today while I was out there tinkering. When I first start the car up after it's been sitting overnight, it will produce the "mist" and I can see a small leak near the FPD area. Once the car gets up to normal temp, there is no more mist or leak. Almost as if the heat seals up whatever is leaking.

I'm figuring either a pinhole leak in one of the rubber lines, or the FPD is bad. I think I may just go with the SARD regulator, anyone know the best place to get one?

thanks,
Mike

 

There's a hose clamped to a fuel line back there as well.

You need to remove the UIM to get a really good look at it.

 

+1, possibly the fuel line near the firewall, mine had the similar problem, it was actually the rubber fuel hose that started to crack, then every time when the temp in the engine bay builds up, the rubber contracts while the metal pipe expands very slightly, and it seals up the leak, every time when I had the car sit over night, i would see and smell a light leak. I also had a failing FPD though, so it would be a good idea to change it if it's old. Good luck!!!

 

That makes it seem to me like a rubber part (hose or seal). When it starts to leak, the gasoline swells the rubber and it seals to the metal tubing or closes the crack, then while it is parked, the rubber dries out and shrinks, and it leaks again.