Hello Everyone, I am new to the rotary world. I just purchased a new to me sand rail that has a 13B with a Single Turbonetics T4 turbo running a stand alone Motec m4. I do not know the size of the injectors. The car runs on 110 Race gas and I am premixing (with Idemitsu) at a 2oz per gallon ratio as I do not have the OMP.

So this past weekend I noticed the FPD was leaking so I replaced the unit with a brand new one from Mazda. I also used brand new grommets when I reinstalled the primary rail. I did not not unplug any sensors or Vacuum lines.

Now the car is running very rough at idle and is idling between 1200 and 1800 RPMS and I am getting some smoke when I rev the motor, plus there is some smoke coming out of the wastegate.

I have now reinstalled the primary rail 4 times with no change, plus sprayed carb cleaner over all of the vacuum lines with no change to the idle.

I am supposed to take the car out in two days and I do not feel safe driving it this way.

Can anybody please help advise on what might be wrong?

 

I realized the primary rail is not sealing correctly. Any tips on how to get this to seal better?

 

Not sealing where

 

The injectors into the iron are not sealing correctly. I tried two sets of beans new grommets with the same results.

 

Is the spacer under the rail mount point?

 

It is in place

 

You can put a light amount of rtv on the grommets to help them seal but it doesnt sound like it's your problem. A vacuum leak at the primaries would be pretty small and it shouldnt affect the operation as much as you're describing. You sure you dont have any issues somewhere else and what method did you use to isolate an air leak at the primaries?

 

At this point I am assuming that is the problem as nothing else was touched. The motor has no smog equipment so getting the rail in and out is very easy and does not require any other sensors or vacuum lines to be disconnected. I will be honest that I am pretty lost now at this point with this motor.

 

Considering what you replaced and going off what you're saying, it's hard to accept your issue is where you believe it to be considering the symptoms. Its not at all typical to get what you have from replacing the fpd and not have had touched anything else. I'm not sure of your set up where you can remove the primary rail without removing the upper manifold but I would advise going over everything again. You may have inadvertently touched something. Check the map sensor vacuum line wherever that may be

 

Knock the vacuum line off the fuel pressure regulator? That would dump in extra fuel

 

Thank you guys for your replies! Today I am going to go back though and recheck everything that could have possibly came undone when I worked on this as something seems off.

 

So I have gone back through the whole car again and cannot find any issue. I used a small amount of RTV on the grommets and it sill idles very poorly. I put a vacuum guage on it and its pulling between 9-15 pounds.

Checked the line to the FPR and its sealed with no issues.

Any other ideas?

 

take a bunch of pictures or a very detailed video.... maybe we can see something

 

I think I have figured out the problem after speaking with the person who built the motor. I was premixing too heavy plus there was some old fuel/premix that had become like caramel at the bottom of the tank. After checking multiple things we came to the conclusion this was the issue. I’m taking it out to the sand dunes tomorrow and I will report back. Thank you for all your help!