Hello my friends, recently I have note a higher gas consumption, my turbo map is incorrect(10-8-7-5psi) and smell to fuel into the car under boost up to 4500rpm.

I have seen articles with the FPD elimination and primary cause of fuel smell problem's and fire under hoods.

My question is: what is the possible problem and the solution? Would must I eliminate this FPD?

Thank you for help me

 

you can do a pressure test of your fuel system and see if you can find a spot where it is leaking from. Another thing is to just eliminate the FPD and follow the right up that banzai racing has on their site. If you are going to do it make sure you have a FPR that has a built in FPD.

OR just replace the FPD with a working one that doesnt leak.

 

Please don't drive the car until you know exactly what the problem is.

 

Yes this is my worry, when I smell on yesterday I remmembered one post of this forum with pics of a fired car by a problem in his FPD. I don't drive the car until I resolve the problem.

I have read the problem can be the LIM gasket, I wait this is not the problem, because is so hard dismount this manifold.

I have fuel injectors o'rings at home, I think I'm going to start to change them and the FPD.

One question, Can I eliminate the FPD and run with stock FPR?

 

Chiribuki,

I had a similar problem to what you describe. The smell of fuel was very bad the more I accelerated.

It turned out that the fuel line under the UIM (where it bends into a U shape) had split very badly indeed and there was a pool of petrol sitting on top of the engine block. It was a simple and cheap fix (just replaced line with same size hose) and all was well. I think the water pump had to be pulled out to be able to get at it! Just be careful of the OMP lines and the electrical cable that goes to the OMP also. When I put it all back together the electrical cable for OMP was not clipped back in correctly and it was loose and got chewed up by one of the pulleys.

I would not drive the car while you have a fuel leak as I am pretty sure that this or something similar is your problem.

Good luck!

 

I think in that too, but I mount new lines when I made the vacuum hoses job, can be one clamp bad mount or tighten in excess cutting the fuel line, but is curiouse I only smell fuel into the car( in cabin) and when I accelerate to max the gas pedal and when the secondary turbo spooling up 4500rpm, in the engine bay at idle I don't smell fuel.

Ah, my car has a middle fuel consumption of 30 liter per 100km, is normally that? I had understood the normally consumption is over 16liter per 100km.

 

If I remember correctly, you need an FPR that can perform the same function as the FPD. The stock FPR can not perform this function. However, some aftermarket FPR's do function to as an FPD. There have been threads on this subject - search for FPD elimination...

Here is a useful thread: https://www.rx7club.com/showthread.p...pd+elimination

 

if it truly only smells under boost most likely you have a leaking LIM or leaking injector grommets. run the fuel pump with the engine off and see what is going on

 

+1
Thats how I located my leak...forgot to mention.

 

I wait that is not true, LIM is so hard to take out, Oh my god.

 

My guess is it's leaking past the injectors. Is your idle higher then normal at all? Get a boost pressure tester, either buy one or make one and pressurize your boost pipes and engine with air. if fuel is leaking past the injectors so is boost which could help explain your boost pattern, though that could just be a problem in your rats nest/solenoids. But since your boost tappers off the fuel smell would go away as less fuel is being pushed past the injectors by the boost. When you pressurize the system listen for air leaking out around the injectors.

I had this problem except I wasn't boosting yet so i just had a major vacuum leak. Turned out the injector diffusers/o-rings were missing from the primary injector bores.

 

It has been 4 yrs now...and before that my brother said same thing. Fuel smell under heavy accelleration.

Find out the smell came from the open end hose bottom of the charcoal canister. Since then I have this hose routed all the way back to the differential...smell still there but very light.

 

My idle is good 800-900rpm, I have revised the solenoids and vacuum hoses 3 times since I bought the car. Now I think I have this boost pattern by the pills. When I did my vacuum hoses job I didn't saw the pills in the old hoses and I have made a new customs pills with 1.5mm inlet hole.

I can take out the UIM and jumping the fuel pump and see if I have leak of fuel by injectors, isn't it?

 

Yes exactly this is my problem, in resume: very light smell under heavy acceleration.

 

If you have replaced the rubber vacuum hose between the UIM and the ??brake cylinder?? remember to put in a one way check valve! There is one included in the original pipe, it's just so small that you can barely see that the pipe is a bit wider where the valve is located

 

Please can you show me that?

 

I'll try to take some pictures for you later today.

 

In the picture below the hose is the one in the red circle and the arrow is pointing to where the valve is inside the hose, my car is a right hand drive but I think it's the same on a left hand drive car...

 

If its the seals at the injector you probably won't see the leak without a boost pressure test because its not actually a fuel system leak and even if there was fuel leaking at the injectors it can just go into the injector bores. So if is the same issue i had the only way to test is by pressurizing the intake and boost pipes

 

Identifying the suspicion was simple, I connect a long rubble hose from the canister into the cockpit, took a hard drive, then there it was.

Verdict charcoal canister.

 

if this hose has a white/yellow dot painted on then the valve has been removed...think this was one of 3 recalls by Mazda. Mine doesn't have the valve inside the hose.

 

so what happens if the check valve is removed? Fuel smell....or....? Is there any other effects from removing the check valve? Mazda apparently thought it should be there when they originally designed the car, until people were having braking issues when the valve failed to open. Mine has been removed (white dot) but I have no fuel smell under boost or any other apparent side effects. Is there any negative effects from the brake booster seeing positive pressure? Just curious what the deal is with this.

 

On US cars, there are two hoses which connect the brake booster to the UIM. At first, the check valve was located on the line which runs from the UIM to the hardline. However, due to the location (hot side of the engine), Mazda had reports of the valve failing. They did a recall to relocate the valve to the other hose which is on the US driver's side. You might check to see if that's where your check valve is now relocated unless you know for sure you don't have it in either line.

 

My car doesn't have this valve, I put a new hose and I didn't saw any valve in the old hose.

I have one new set of injectors o'rings in stock at my garage, I'm going to mount them and I think I will can to be sure I won't to have fuel leaks by injectors.

What do you think?

 

I think you should pressurize the intake instead of just arbitrarily replacing parts. Getting a pressure tester or making one is so easy, its way easier then replacing the orings or the seals on the diffusers. I don't think its the injector orings if anything its the seals on top of the diffusers. But your idle is low so it may not even be that. Don't guess on things when there are easy enough ways to test. All you need to do is disconnect any pipe going from in front of the throttle body and put a 3" or whatever fits best pipe thats welded closed on one end with a tire valve threaded into it. Then fill it up with compressed air, listen for leaks.