Exhaust manifold removal

[98rolla_ny]

I have a 98 corolla and wanted to replace the exhuast flange gasket (donut gasket) since I believe it is leaking, causing a slight buzzing sound and sapping some torque during heavy acceleration. I figure I replace the exhaust manifold gasket while I'm at it, since the car is at 145K, it's only $10 part, and it's not like I'm planning to take off the exhaust manifold anytime soon.

So the problem come after I remove the upper heat shield. I see the bolts holding the manifold to the engine block, which are not hard to access and remove. But the two spring bolt at the bottom of the manifold are difficult to access from the top of the engine.

I got under the car and I can access the passenger side bolt of the exhaust manifold. However, the driver side bolt is blocked by the O2 sensor. I can remove the O2 sensor, but it looks like the backet the holds the O2 sensor to the pipe protrudes just enough to block the bolt from the socket getting a good seat on it. The cross member under the car is no help either.

I consulted the Hayes manual but it don't see the backet bolts they are referring to under the car. The manual doesn't even mention the 02 sensor in their removal procedure. Or are they suggesting I unbolt the flex pipe before the catalytic coverter and pull the exhaust manifold and flex pipe from the top of the engine bay.

So I'm a beginner that can change the oils and other wet stuff in the car. I can swap the suspensions stuff, and brake stuff. Even changed the valve cover gasket on this 1zzfe. Plan to keep the car 4ever, which shouldn't be too long since 2012 is just around the corner...but just in case the world doesn't end next month...I need this daily driver in good shape.

Am I missing something? Do I need a really long socket extension to loosen the bolt from the top? Or is there something else I'm suppose to unbolt from the bottom to remove the exhaust manifold.

[Bennie]

If it were me I wouldn't mess with the manifold gasket. You will need to remove the O2 sensor, then you can unbolt the down pipe from under the car. It's still a bit of a pain to get the old doughnut out and the new one in so take your time. These cars tend to wear them out quite a bit. I think it's because the don't actually have flex pipes so all the movment happen on the doughnut.

[markzbornak]

I just replaced my doughnut over the weekend. I drive an 01 Corolla, and I had to remove the o2 sensor to remove the bolts and springs you are referring to. Get an extension for your ratchet and it will make things a lot easier. Also, make sure to spray some PB Blaster on the bolts/springs and let it sit for a bit before trying to remove them. Go slowly at first because I am sure you do not want to have the bolts break on you. Once those are off, it's a pretty easy fix.

This is slightly off topic, but since we are talking about exhaust, here goes....

When I was looking at my car last weekend I notice what appears to be standoff bolt ends protruding from the engine with the exhaust manifold fitting around those. THEN, there are nuts that tighten over the bolts and the manifold. Has anyone else seen this on their Corolla? If so, would that mean that replacing a manifold on an eighth generation Corolla is much easier than some other cars. i was under the belief that most other cars had the exhaust manifold bolt INTO the engine block.

Thanks for the validation if I am right, and thanks for correcting me if I looked at it wrong.