air leak How would i Change The Intake Manifold Gasket

[jonjoe]

Hey Guys I Think I Found A Air Leak In My Intake Manifold And Was Wondering How To Change The Gasket The Idle Is Running Low When Warm So I Think Its The Leak Causing It Could I Do The Gasket Myself Or Do I Need To Leave It In Whats The Best Way To Do It Its A Irish 05 Corolla Terra....

[Cman46290]

Uh... take off the intake manifold?.....and Change the gasket....

[tranxrs]

shouldnt be to hard

[JasonA]

An intake leak at the gasket would produce a high idle, not a low idle, right? From the very brief description of the symptoms, I'm not sure you have an intake gasket leak.

[jonjoe]

thanks for the reply jason...i didnt do the gasket yet ..what do you think it could be causing it to idle low i cleaned the throttle body and iacv and the maf sensor new pcv valve and new air filter and cabin filter spark plugs are only 10 months old all Toyota brands stuff its still running low idle when the car warms up after about ten minutes there's no lights coming up on the dash or anything has me puzzled i also got a scanner/code reader and nothing on that ider.....thanks

[JasonA]

How low is the idle? Can you further describe what it does? Does the idle raise when the A/C is on? Yours is an '05 -- does it have a throttle cable or is it drive by wire (DBW)?

[bigkat91]

The air idle controller could be out of adjustment???

[tranxrs]

when there is a leak the maf doesnt detect as much air going in the engine so the amount of fuel isnt matched to it, so you would have less power and possibly lower idling.

[JasonA]

Typically when there is an intake leak, you get more air sucked into the engine than the ECM realizes (depending on the size of the leak obviously). The O2 sensors see the extra oxygen in the exhaust stream and the ECM compensates by adding additional fuel to stabilize the fuel mixture. You typically see an increased idle speed with an intake leak. The common method for finding a leak is spraying the gasket area with throttle body cleaner. When the throttle body cleaner finds the leak, that air pathway is suddenly blocked off, and the idle speed will return to normal.

[jonjoe]

thanks Jason...ill try the throttle body cleaner and see if it finds any leaks the reason why i didn't do that yet is i was afraid in case i got any TB cleaner on the electrics would that do anything to them i mean like if it was dripping after i sprayed it wasn't sure if it was safe..???

[JasonA]

Originally Posted by jonjoe

thanks Jason...ill try the throttle body cleaner and see if it finds any leaks the reason why i didn't do that yet is i was afraid in case i got any TB cleaner on the electrics would that do anything to them i mean like if it was dripping after i sprayed it wasn't sure if it was safe..???

Well, you're not soaking it. If the 1ZZ-FE in your Irish car is the same as the one in the U.S., there are really only two seals on the intake manifold. One seal up at the throttle body and one long seal down at the engine, where the plastic manifold bolts to the cylinder head. Take the upper plastic engine cover off and find where the manifold bolts to the engine. Spray some TB cleaner (lightly) at the seal area with the engine running. Try to get around the whole seal. You may need to do the same up at the throttle body area, but if there's a problem with a seal, it's likely the gasket down where the manifold bolts to the engine.

You still haven't said how slow the engine idles, or if it sputters, etc. If you can fully describe the symptom, and if the idle changes when the A/C comes on, if you have a DBW throttle body or cable-operated, we can help you more.

[jonjoe]

thanks Jason
when the car is cold first thing in the morning it seems to be OK but after about 10 15 mins when the car gets warmed up the idle drops to between 600.650rpms i can see it going up and down abit it fine at about 800/750rpms so when I'm stopped at lights or parked the car shakes abit like its trying to cut out but doesn't its only like that about 3months the cars seems a bit jumpy till i get to about 4 gear its like it wont settle the car its gone a really horrible drive now i do really looked after all the cars i have had..this car has no A/C we kinda don't really need it here in Ireland weather stays the same no sun just clouds lol....there is i cable under the hood beside the throttle body that's how i thought i had a leak cause when i reved the car from the cable i thought i could here air for a second then it would stop so i tried revving it a few times the same thing like a air noise from the intake then it would stop after i would take my hand off the cable....i can see the engine shaking when i look under the hood its not to bad cold just the warmer it gets the worse the idle is and seems more shaky

[JasonA]

It does seem like an idle air control motor issue. I'd think that if it were a vacuum leak, it'd show up cold also. Then again, you get some thermal expansion differences between metal and plastic that might show a leak only when hot.

[jonjoe]

thanks for the reply Jason...there's just one more symptom i have notice about the low idle it confirmed it today when it was raining...when it is raining out it seems to idle normal only when it rains really wired would the rain be cooling the car down to make idle normal..also i notice when it rains a small bit of white smoke well i don't think its smoke more like steam comes from the hood i don't know if the heat of the engine does that to a wet hood only happens when I'm at lights or parked idle when it rains its happened the the past 3 rainy days never seen that before in this car not sure.also the radiator fan came on yesterday when i got out of the car that never happened before for about a minute then it went off the car was off the fan just kicked in no key in or anything.....