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View Full Version : 4A-fe exhaust manafold cracking



david in germany
06-18-2008, 07:36 AM
Ok who else has had this problem? I am on my second manafold in the celica and just ordered the 3rd one! They usualy crack almost center under the heat shield.. I did weld mine yesterday but I can still hear it leaking somewhere under it...

All of you other 90-93 st owners should check yours if you have never done it. You may have an unpleasent suprise... :(

On a side note, The manafold took the weld quite nicely when it was hot. I have tried to weld cast iron before when they were cold and that was not a good idea. This time I just got home with the engine at operating temp and left it running. It worked like a charm!

CHRiS'_CeLiCa
06-18-2008, 06:04 PM
I think I have two cracks in mine...heh...Even on the second engine I bought a month or so back had a cracked manifold worse then the one i originally had, so I just kept the original...Are the cracks bad?...Bad for the car or just emissions?...

david in germany
06-18-2008, 08:28 PM
Bad for your health as well as emissions.. Exhaust should come out the back of the car, not the front!

burnyd
06-18-2008, 08:30 PM
^^ lol yes.

Cavanagh
06-18-2008, 09:12 PM
Good call DiG, when i had my ST, it had an exhaust leak somewhere around that area as well as the cat.

ciento44
06-18-2008, 09:13 PM
Good call DiG, when i had my ST, it had an exhaust leak somewhere around that area as well as the cat.


I have an exhaust leak somewhere around my passenger door.... :burn:

donteatbugs
06-18-2008, 11:45 PM
i have an exhaust leak out of my midpipe. i need a new one anyway.

Ghosty
06-19-2008, 12:24 AM
I don't think I have one. Then again, I don't know the symptoms of a cracked exhaust manifold. Is there any way of finding this out without taking off the heat shield?

Must be a poor design :( Any idea if a Pacesetter aftermarket exhaust manifold would suffer the same problems?

CHRiS'_CeLiCa
06-19-2008, 04:35 AM
how can it affect the health of my engine?

david in germany
06-19-2008, 05:11 AM
It will cause an incorrect reading to the o2 sensor but I was talking about YOUR health because you shouldn't be breathing the exhaust through the fresh air setting of the car.

david in germany
06-19-2008, 05:14 AM
I don't think I have one. Then again, I don't know the symptoms of a cracked exhaust manifold. Is there any way of finding this out without taking off the heat shield?

Must be a poor design :( Any idea if a Pacesetter aftermarket exhaust manifold would suffer the same problems?

Do you have a "header" or a manifold? I had the pacesetter header on the celica for a year or 2 and did get some leaking around the mounting point to the head.

You can tell if it is leaking if you hear an odd sound in different RPMs, kinda like a valve ticking most of the time.

Ghosty
06-19-2008, 06:43 AM
Do you have a "header" or a manifold? I had the pacesetter header on the celica for a year or 2 and did get some leaking around the mounting point to the head.

You can tell if it is leaking if you hear an odd sound in different RPMs, kinda like a valve ticking most of the time.

Nah, I have the stock manifold right now. I was just asking if the Pacesetter would be better, considering the defects in the factory part.

What range of RPMs are we talking about? Low, Mid, High?

david in germany
06-19-2008, 09:08 AM
Nah, I have the stock manifold right now. I was just asking if the Pacesetter would be better, considering the defects in the factory part.

What range of RPMs are we talking about? Low, Mid, High?
The rpm range depends on the crack, it varries. Stay away from the Pacesetter. The O2 sensor is in the wrong location and it causes problems with the computer as well as not being the proper lenght. The pacesetter is also a iritatingly loud compaired to stock on the 4afe.