I Have been putting my car back together and wanted to check for leaks in the fuel system. So I turned the car on and no leaks. Good. What bothers me though is the fuel doesn't stop spraying. Currently the car has the uim off and the runner on the lim closest to the firewall fills with fuel and doesn't stop untill i turn the car off. Any idea what could be the problem? I recently had the injectors cleaned and they came back good. So i'm lost. Also what is the secret to get the gas cap to close?

 

What do you mean about the fuel doesn't stop spraying?

If you mean there is fuel spraying out the injectors, then your injectors are stuck open. If you mean you can hear the fuel pump pumping, then that's also not normal. (To run a fuel system pressure test, you ground the FP relay, which makes the pump run whenever the ignition is in the ON position).

When I ground FP relay there is no fuel sprayed from the injectors until I apply voltage over the injector connection.

Dave

 

what i mean is that the fuel fills up the lim. I'm guessing the pump is working fine. Wouldn't stuck injectors have showed up when i got them cleaned?

 

fuel is filling up the lim??

where it bolts to the block??
are the injectors mounted properly?

not sure if I know exactly what is happening here but you should NEVER see any fuel ANYWHERE.............obviously

 

Are you sure the fuel is coming from the injector and not from 'around' the injector (i.e. bad o-ring)?

I had a similar problem and it was the o-ring supplied by RC Engineering was leaking. I replaced it with an OEM o-ring and all was well.

 

cleaning and balancing was done by witch hunter. I guess i can yank them out. Its not that hard anyway, and buy some new orings. Witchhunter did replace the old ones though. Do they expand when you add the engine oil to them. I forgot to do that step and they slipped in fairly easy anyway. So i figured the oil was to help them slide in.

Thanks for the help.

 

Here's a good way to test them and see what's happening:

https://www.rx7club.com/showpost.php...&postcount=255

 

Something is way wrong if you're filling your LIM with fuel.

The oil is necessary to keep from pinching and damaging the orings during installation. I'll bet that's what happened. Unbolt the fuel rails and lift them clear of the block, then pressurize the fuel system again. A stuck open injector will leak fuel from the center of the pintle cap. A bad o-ring will seep fuel from around the bore in the fuel rail.

I suggest you call witchunter and buy another set of o-rings. (You don't wanna buy them from Mazda or try to find them elsewhere). If the injector was leaking internally and out the top (it can happen) it's fairly safe to assume witchunter would have found that.

Dave

 

great....are the ones from rotary performance bad?

 

Oh, they're probably fine too. It's just that mazda o-rings are insanely expensive and nothing special, and most performance / injector shops don't have o-rings in the right size unless they specialize in FDs.

 

ok. I'm hoping since they seem to be a reputable rx7 shop, they know the right size. I checked all the injectors and they are all opening and closing properly i believe.(apply 12v to them and listen for click). I'm gonna go ahead and order some new orings and hope that fixes it.


One other quick question
The fuel lid in the trunk under the panel. That thing that looks like a ground is just a ground right. I was swapping fuel pumps and broke it off. Since it just seemed like a ground I just grounded the wire to one of the screws that holds the lid on. My only concern is that on the underside of the lid, it look like it maybe a sensor, or a bolt that was welded on hopefully. Either way, let me rest by confirming it is just a ground. I couldn't find it in the wiring diagrams.