Hi all,

I have a 91 JDM T2 where I am redoing all the vacuum lines/cleaning up the engine bay.

I spotted this vacuum line just sitting there not hooked up. I have a KnightSports EBS3 controlling boosting duties, does this vac line have something to do with this?



The car ran fine before I decided to tear out the AFM and whatnot. I wanted to check the shaft play on the turbo just to be sure everything was good.

Thanks in advanced ! I just want to know if I need to cap this line or if I can just leave it alone since it wasn't bothering the car before.

Cheers,

Kevin C.

 

Bump, I'd like to get the car ready for my race day and I don't have any vacuum diagrams to look through .

 

isn't that hooking to the wastegate?
When I had no boost controller I ran a hose from the turbo inlet to the wastegate.
after I had one,I put the boost controller between those 2 points.

 

Yea that's for the waste gate.
And am j blind or to me it looks like you have your waste gate hooked up to the water pump (water return for turbo).
Maybe I'm crazy....

 

Agreed with both above posts. Line goes to WG or boost controller between the two points. Also agree it looks like your WG is attached to the water pump port for the turbo coolant return.

FSM's for diagrams...
Foxed.ca - Mazda RX-7 Manuals

Or what I found searching through the forum attached...

 

Um...are you guys serious? Holy crap.

Okay, just looked at that vac diagram and you guys are right.

Any reasons why the previous owner would have the boost controller hooked up like this?! How has this not failed and ruined the boost controller solenoid?

Alright well, obviously I have some work to do...this is very strange.

 

How was there not coolant puking from your wastegate actuator would be the better question. Can't imagine the diaphragm holding that back...

EDIT:

The only hard line not taped up on the bottom is the turbo coolant drain that goes to the water pump housing. Between the exhaust manifold and compressor cover. 180-degrees opposite of the water inlet on the CHRA.

 

Don't mean to double post but I can't edit the above post again for some reason. I looked at your pic again and it looks like you might have the coolant drain for the turbo hooked up correctly.

Your pic is really blurry but it looks like the WG (dirty blackish with some red showing) line and the line that normally goes across the engine to the stock boost control solenoid (again blackish dirty with red showing) might be the ones that go to your KS boost controller. More pics, possibly clearer?

 

Yeah, I just checked, and you're right.

The stock boost solenoid line was cut near the vacuum line on the turbo and it's just hanging there. The KS EBS3 has 2 lines going into it (the 2 dirty/red lines in the picture).

Since I don't believe it's causing a vacuum leak, is it okay to leave it as is? Or should I plug that vac line?

 

I would move the line down to the bottom nipple and cap the "T" nipple that would go to the stock boost control solenoid. But you could just cap that nipple thats loose without a problem. As long as your boost controller sees the compressor housing pressure and WG you'll be fine.

 

The coolant line looks fine. The hardline from the turbo is just hard to see. If the boost controller has an alternative pressure source, the metal line on the front of the turbo isn't necessarily needed. But the line from the turbo compressor outlet appears hooked up, which would be a large boost leak with that end uncapped. Cap it and use a hoseclamp or use it for a pressure source for the boost controller.

 

Thanks for all the amazing help ! I will definitely cap it and clean up the install. Thanks again everyone!