Intake Gasket

#1
I have heard that the stock intake gasket for the Corolla can fail/leak, leading to erratic RPM. The revised gasket (orange in color, not black) fixes this problem. I have never had a problem with my own stock gasket but, in order to be preventative, I ordered the revised gasket. After installation I have experienced erratic RPM and it even stalled once.

I have checked and rechecked the seals, cleaned the intake manifold till it shines, and triple checked all the hoses, the intake boot, and bolts, making sure everything was nice and tight. Obviously there is still a seal problem somewhere. In installing the new gasket I was told that using throttle body cleaner would be sufficient; is there any sealant I should be using or oil to create a better seal?
 
#2
Sure sounds like a vacuum leak somewhere. The way to diagnose this is to use a pump spray bottle of water to spray all gasket area's, vacuum lines, hoses etc. Do this with the engine running and slowly spray an area a small section at a time. If you suddenly spray an area that makes the idle change, you've found the vacuum leak. What happens is that the water acts as a momentary seal and the engine idle changes.
 
#3
You were both right. I had a vacuum hose loose (found the leak using the water technique, thanks for the tip) and the engine took a few start-ups before the ECM relearned. Thanks for the quick reply! It's running smooth.
 
#5
Oh I am completely addicted to cars ever since I saw Fast and Furious when it came out. I'm not really into the street racing side of things, but there is something about taking a piece of machinery apart and modifying it. And when it turns over and everything works-priceless! The mechanical side of cars is simple enough, I am having a larger learning curve with the electronic side.
 
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