2003 1ZZ Rough Idle, Low Idle, Air Leak??

[04shadowvibe]

So my girlfriends 2003 base Vibe 1.8 1ZZ, has 71k on it and its giving her its first problem. Cold starts the car is fine. On a warm start, the car struggles to idle, can be as low as 300 rpm or so. At first thought it was bad gas, dumped some stuff in the tank but the problem continued. Started it warm yesterday and had the hood up and i could hear an air leak while the engine is running. If i gave the car some gas, it would sound almost like a turbo engine, it would make a sneeze noise, then as the rpm comes up you could hear air rushing, and as the rpm came down it would sound like a blow off valve. I am thinking its the Intake Gasket that has failed.Has anyone changed this before? What is the procedure for removal and the torque specs on the bolts?I ordered a gasket from my parts guy, so I hope this is the problem.

[lovemyraffe]

I've changed my intake manifold gasket. It is fairly quick if you know what you are doing. You need to remove the intake tube and throttle body before the intake manifold can come off. I don't know the torque specs though.

[star_deceiver]

Did you check all the vacuum lines/hoses/connections just to make sure something's not loose or broken?

[northvibe]

didnt 03's have a heat soak issue? I would bring it in to see if you need a ecu flash. I swear that was one of the fixing for it. Otherwise search this site for heat soak. edit: ah read the full first post, sure if theres a leak it could be that too.

[SonicThunder88]

The gasket might be the problem but I have my doubts - these gaskets do fail but usually exhibit the symptoms when in a cold (-0C) or colder starts and usually are accompanied by a SES light on. Although not as common a problem these days, the one thing I would check is the flexible air tube that runs from the air filter box to the throttle body. These used to be famous for cracking and letting un-metered air into the engine thus giving the symptoms you describe. Of course check things like the hoses to the PCV valve and the brake booster as well - all will give you your symptoms as well if they are split, cracked or slipped off their port.Let us know what you find and what fixes it.Cheers

[tunertype]

Quote, originally posted by 04shadowvibe »Has anyone changed this before? What is the procedure for removal and the torque specs on the bolts?I ordered a gasket from my parts guy, so I hope this is the problem.Yeah I would check for other sources of the leak besides the gasket. Has it ever been overheated? The plastic crappy intake could have melted, had that happen on a car. Anyways here is a link to the celica(celica has same engines as vibe 2003-2007) tech manual http://www.newcelica.org/other...2.pdf pg 42 has an engine diagram with torque specs the torque for the intake is 14ft-lbs. the manual also has a diagnostic table in case the gasket doesn't fix it. My first idea when you said it happens when warm is that one of the coils could be bad when warm. You would get a CEL(check engine light) for engine misfire though for that. you can test this when you have it warmed up and are experiencing the problem, by disconnecting the connector to each coil and if it doesn't change the sound of the engine like that cylinder is missing then that's your problem coil. electrical parts can be sensative to heat. But the vacuum leak could be the problem to, as when it's warm it goes into closed loop operation and the maf wouldn't be sending the right signals. You would be running lean though, so vacuum leaks usually cause higher idle or surging or knocking.

[04shadowvibe]

Well thanks everyone for their input. I havent seen the car all week but i know its still acting up. As far as I know it has never overheated. She has owned it for the past 20K and no problems at all. I forgot to mention there is no check engine light on.Im going to pull it all apart Friday and check it all, flush the cooling system and replace the coolant, change that intake gasket and see if everything is connected.

[northvibe]

Quote, originally posted by 04shadowvibe »Well thanks everyone for their input. I havent seen the car all week but i know its still acting up. As far as I know it has never overheated. She has owned it for the past 20K and no problems at all. I forgot to mention there is no check engine light on.Im going to pull it all apart Friday and check it all, flush the cooling system and replace the coolant, change that intake gasket and see if everything is connected.I didnt mean over heat, I meant heat soak. It was a issue either the 03's had or 05's. I know the 05's but I swear some 03's had it and its a pcm issue. where when the engine is warm and you try and start the car it wont start or has many issues starting.

[04shadowvibe]

well this seems to have just started within the last few weeks. Still no CEL, I disconnected the MAF and let it run for a bit and it seemed to run alittle better. Gotta put a battery in it now, the factory one died this morning after 6yrs and 11months.

[northvibe]

clean the maf, iac valve, maybe replace the pcv. Also check for o2 sensor issues and a clogged cat.

[04shadowvibe]

Well I changed the gasket, cleaned the intake and everything that goes with it and the gf reported to me today that the rough idle has not been a problem and the mpg is back where it use to be. So problem is fixed thanks everyone

[DoubleBaril]

Looks like I will be changing the intake manifold gasket too.Ive done most of the other steps (well, the easy ones anyway).