Hi all, I have bouncy idle and was thinking it could be a vacuum leak, already check the tps and its within spec. I did a smoke test and i found smoke coming out from somewhere behind the air pump and waterpump area. I'm not sure what would be in that area. any clue/ help would be nice. thx

 

Did you miss something??
https://www.rx7club.com/new-member-r...swers-1030345/

 

Sorry, just remember after i post it, 1987 rx7 na and no mods.

 

Not certain on your year, but on a 93, that is exactly where intake manifold gaskets sometimes fail.

A can of carb cleaner while running the motor will prove if this is the leak. If you get the leak spot with a stream of cleaner, the idle will smooth for a second.

Good luck with this

Rich

 

I dont think so because the smoke flows from like behind the waterpump to in between the air pump and waterpump and up.

 

My idle Is jumpy from 300-400 rpm in my FD, I checked for leaks and cant find any, Im aiming at its my tune, since I didnt buy this car stock in the first place.

 

That is definitely way below spec. OP maybe made a typo. Did you check solenoids during hose replacement? I'm guessing that the 87 na doesn't have restrictor pills in any lines.

 

There are a couple vacuum hoses in that area.If you look closely at the area just at the back of the water pump,you can see the Steel lines of the emissions "rack".
Check the hoses on that Mess of lines.
The oil injectors are also run by vacuum too and go to a big "spider connection".4 hoses into one.
You can get the vacuum hose routing off the Factory service manual
Foxed.ca
Or try a search on forum here,,it has been posed before,I actually used it recently.

 

I use a can or carb cleaner and start shooting near possible vacuum leak. Idle jump up and soon as it hits the leak

 

what will be the easiest way to get to the area? what should i remove to get to it?
also, looking at the vaccum routing, which one may be the cause. cant really do anything with the car till the weekend.

 

I had the bouncing idle on my FD, spent hours trying to figure it out, and it turned out that the throttle had stuck open, and I'm assuming kept the secondary butterflies open, freaking out the ECU. Just tapped the little actuator and it went back to normal. You might check that, since it should be similar in setup.

 

x2 on bottle carb cleaner....... Mine leaked at UIC found fast

 

found my leak, lower intake manifold gasket. T he gasket crack and part of it sticks out. thanks everyone for your help