Exhaust Leaks

[66yostagea]

As you know I am fixing some exhaust leaks.

What do leaks do to the ecu system? AFM, O2 sensor etc, and what are the theoretical affects on power and fuel consumption?

[SHIZNT]

Good topic, I'm wondering if my turbo manifold is leaking at the moment as my car has been hitting a flat spot lately where you can hear the turbo spooling but the car doesn't really move then it finally takes off. Not sure if its a leak or trans needs a service.

[STAGE1]

As you know I am fixing some exhaust leaks.

What do leaks do to the ecu system? AFM, O2 sensor etc, and what are the theoretical affects on power and fuel consumption?

Hi Hugh

I had a similar problem a while back. It did not seem to make any difference to fuel economy as there was still enough exhaust gas going passed the o2 sencer. Power felt a little down (could have been in the mind) as what was escaping was not being used to spin up the turbine. One second hand manifold and 12 new studs later and all is good again.

Cheers

Phil

[66yostagea]

Thanx Phil.

Why did you get another manni? Was yours distorted, did you have any broken studs??

[66yostagea]

My mannifold is only .1 mm out of being perfectly flat. So I dont need another or to get it ground.

[STAGE1]

HI

Mine was in a bad way it was cracked in two places. I also had two broken studs on 5 and 6 cylinders and it was also loose on the back three probably because of the missing studs. That is why I replaced all 12 studs.

Cheers

phil

[BensDR30]

HI

Mine was in a bad way it was cracked in two places. I also had two broken studs on 5 and 6 cylinders and it was also loose on the back three probably because of the missing studs. That is why I replaced all 12 studs.

Cheers

phil

snap...

I've just bit the bullet & started working on the rear stud replacement. Unfortunately after removing the main shield, I've found a 40mm long crack just in front of the turbo flange. So it looks like I'm up for a new manifold.

Edited November 30, 2008 by BensDR30

[KiwiRS4T]

snap...

I've just bit the bullet & started working on the rear stud replacement. Unfortunately after removing the main shield, I've found a 40mm long crack just in front of the turbo flange. So it looks like I'm up for a new manifold.

A second hand one should be cheap enough but welding and machining flat should be cheaper than a new one.

[BensDR30]

A second hand one should be cheap enough but welding and machining flat should be cheaper than a new one.

A new one is $600, I'm in two minds as to whether I go for a second hand one (which may crack after 5 minutes), get mine re-welded or go new. I have had success with cast-welding before, but not right in the middle of a turbo manifold. I expect that after welding & machining both mounting surfaces (assuming it's fairly flat to start with), I will have spent a couple of hundred $. I'm not sure it;''s worth the risk.

It only cost me $440 for a brand new L-series turbo manifold in August...

Bloody exchange rate!

I think I'll order all my new studs/nuts & gaskets and ponder the manifold situation for a little longer.

[66yostagea]

A new one is $600, I'm in two minds as to whether I go for a second hand one (which may crack after 5 minutes), get mine re-welded or go new. I have had success with cast-welding before, but not right in the middle of a turbo manifold. I expect that after welding & machining both mounting surfaces (assuming it's fairly flat to start with), I will have spent a couple of hundred $. I'm not sure it;''s worth the risk.

It only cost me $440 for a brand new L-series turbo manifold in August...

Bloody exchange rate!

I think I'll order all my new studs/nuts & gaskets and ponder the manifold situation for a little longer.

When I started my diagnosis I initially thought it was a buggered turbo. However it finally transpired it was a loose connection into the turbo. I had known before that there was a broken stud at the rear of six, but by the time I got it all apart there was four broken studs and the manni had a crack in the section where the turbo bolts on. I rang around local, Gold Coast, wreckers and got a price of $275 for a manni. Thru Silvia my son got me a manni for $50.

I bought a turbo and will get the manni fixed by a friend so have insurance.

The thing that impressed me about my "simple" problem has been the amount of feedback from members. Which prooves the importance of our Forum.