Psionic

I did a search and I couldnt find what I was looking for so...



I have a HUGE vacuum leak, and I have tracked it down to here. I have some old vacuum line and I use it as a type of "stethoscope" to track it down easier. I slid the hose through the gap (at the arrow) and kind of slid it towards the firewall and found it right where the circle is. I can see that something is there, but the air intake chamber is in the way.

Would it be feasable to simply remove the air intake chamber and find out from there? It doesnt look like too many bolts that hold it on. I just cant reach my hand in there, and I cant really see it with my flashlight. From what I understand, the previous owner changed the sparkplugs and when he put the car back together, the car started running badly. I believe fixing this will fix the problem. Any help is greatly appreciated.

Supra Dr

iTrader: (14)

this is about 40% of my job @ work, fixing other peoples comebacks.
if it were me i would start w/ replacing the spark plugs. while your taking it apart
examine everything you remove. every vacuum connection, every electrical
connection, the spark plug wires. etc., etc. i would replace the spark plugs
also, the porsolin may have been cracked from inproper installation.
you'll probably find the mistery vacuum hose in your travels.

sucks when you have to fix the previous owners comeback for free.

good luck
john

Psionic

Sorry if you misunderstood. I found the leak, but I cant actually see it or touch it. I can use my "stethoscope" to pinpoint it (and even close off the leak if I move it the right way), but I cant see where its coming from. It looks like maybe a hose from the bottom of the air intake chamber to the top of it, but that circle is as close as I can figure where its at.

I just need to know what it is and how hard it is to get to it, then I'm breaking out the tools! (also, I dont know if this helps, but it only starts leaking/running bad when it has been completely warmed up for ~30 minutes or so. If I turn it off, and turn it back on a few minutes later, the whistle aka leak is back).

Supra Dr

iTrader: (14)

its not that hard to get under/in that area. the throttlebody & upper
intake runner (y looking piece in the pic) need to come off.
its probably a vacuum hose off or broken.

search 'spark plug ' or 'replace spark plug' & you'll see numerous
write ups on how to take out those 2 pieces.

the vac hoses for fuel pressure regulator & vsv's are near that area.

check the vacuum chart on your hood label if you find a loose hose
& dont know where it goes.

so after a long sorted story, YES it would be feasable.
pull that sucker out & hunt it down.

Psionic

I was hoping it wouldnt come to that. BUT!! I finally made some sense of the other thread of how to change your spark plugs, and it seems that you only have to remove the upper intake runner (which is probably what the guy before me did...) to get to the spark plugs.

I will try that route this weekend and see how it goes. Should only take me about 30 seconds to fix the leak once I get to it.

Psionic

Found it! It was the lower part of the gasket on the intake runner. It looks like a metal gasket there, but maybe in got kinked or something?? Anyway, some RTV blue rubbed on it took care of the leak. It should hold until the next time I change my spark plugs.

Supra Dr

iTrader: (14)

Psionic

UPDATE!

Before I fixed it, it would slowly lose idle then completely stall. After I fixed it, it ran fine... for about a day. Then the same problem cropped up again. I ran seafoam through the intake and gas tank, and then it just ran smoother... till it got to idle... then it would stall again.

Then it hit me!

The ECU had "learned" that it needed to compensate for the vacuum leak, so it would try to compensate for a leak that wasnt there anymore. The result was dumping fuel to get the air/fuel mixture right again... which made black smoke come out of the tailpipes at idle. I reset the ECU, now the car run at a smooth 500-600rpm... no stalling whatsoever (it idled at 900rpm then slowly dropped before).