4AGZE ISSUES

[Calvin]

Hey guys, I have a 4agze bigport AFM
THe vacuum nipple on the back of the intake manifold has snapped off so i cannot connect the vacuum hose.

What i wanna knowis if this is important or is simply for emission controls? will it affect the performance of my engine?

Also my engine has a very rough idle at the moment. What could this be due to?
Have done the timing and idle adjustment but still seems to be very sluggish and idle is flucuating rapidly.

What could be the cause?

Thanks

[gmacrae]

on the back of the intak mani? like on a single runner? Cant remember the exact nipple you're talking about but if your brake booster is hooked up then just make sure its plugged and the engine should at least run smooth. May have something to do with evap/charcoal cannister stuff. If it isnt plugged up, thats why the car's running rough.

[Crampy]

The only vacuum nipple in the intake manifold I remember on my 4AGZE was the fuel pressure one. It's the one you T into when you do the ABV mod.

I think it's supposed to pull the fuel pressure down on high vacuum, as you're using less fuel. And if it's a proper rising rate type regulator, it'll bring the fuel pressure up as boost comes on.

[Crampy]

Also, the fluctuating idle can be for a couple of reasons.
If not the vacuum line (which it might well be).

Air lock in the water system is a common problem with that.

Also, on my 4AGZE, the warm up idle broke and the idle would jump up and down rapidly from about 1.5k to 2.5k rpm. Fixed it by blocking off all the warm up idle stuff. Just means you have to use you gas pedal a bit to start with until it warms up.

[Calvin]

The only vacuum nipple in the intake manifold I remember on my 4AGZE was the fuel pressure one

Yes that is the one. it runs through a vsv value. so if i just block it off it will run fine?

[Crampy]

I'm not sure if it'd cause too much of a problem. I'd say there might be another problem causing the idle to be rough.

Probably best to get that vacuum line connected somehow though.

[Calvin]

I'm not sure if it'd cause too much of a problem. I'd say there might be another problem causing the idle to be rough.

Probably best to get that vacuum line connected somehow though.

Any ideas .. the small nipple has snapped off and due to its location is not easily put back on. i wil try find a pic.

[Crampy]

I'd say find a way to block that broken off nipple and get one put into the intake piping somewhere near the inlet manifold.

[Crampy]

Try some type of sealant. Maybe locktite or metal set or something. Make sure it's fully cured before you start the car again though.

[Calvin]

Have found where the nipple is. not on the manifold but still on the intake. How easy is it to remove this part?

Have found where the nipple is. not on the manifold but still on the intake. How easy is it to remove this part?

[Pelo]

I'm pretty sure that particular hose goes to the blue supercharger VSV. Part of the boost control system. You can simply block the pipe.
This page may help
http://www.mr2supercharger.com/ABVmods.html

[Calvin]

cheers