Exhaust manifold

[Litahni]

So I am getting an intermittent P0171 code and my car is running lean. I take it to the dealership thinking it has an exhaust leak. Lo and behold, they tell me I have a warped and/or cracked mani. I get on this forum and get the impression that the stock mani is famous for doing this. My car has 79k on it. Well, the OEM replacement for this is over $1,000. Ouch! I don't want to buy OEM replacement if it's the same faulty part. I would much rather get an aftermarket one that isn't notorious for cracking. It looks like aftermarket manis for this car may be hard to find. I was reading other threads where manufactures were only making a handfull of these to sell. So I have a few questions:

1. Does anyone know of a good, reliable manufacturer that makes these aftermarket manifolds?

2. What causes them to crack? Is it heat, shock or a combo of both? If I put an aftermarket intercooler on will it help prevent this in the future?

3. Is there something I can do to quick fix this for now until I have the money to replace?

I'm sure I'll think of more questions; that's one thing I always have plenty of.

Thanks, Litahni

 

[BOOSTR]

Some have cracked while others have not. You do have a few options for aftermarket custom manifolds. Depending on the design/manufacturing process, those can crack too.

Are you sure the stock replacement is $1000? Check with the mazda dealers in the main sponsor section of the forum for a better price. That seems crazy for just the part.

Are you running yours with or without the heatshield? Yours may be repairable by a good welder depending on the size and location of the crack(s).

 

[Litahni]

The dealership quoted me $1075 for stock kit. I'll check out your suggestion. Thanks. I am running with the heatshield. Should I not?

I was reading on another topic in this forum where people are JB welding or wrapping the manifold. Is this a good option for a quick fix until I can afford replacement?

Also, should I consider different motor mounts and attaching the mani to the tranny for better stability so this doesn't happen again?

Are MAM manifolds any good? That's the only maker of aftermarket that I've seen.

Told you I'd have more questions. More answers sometimes produces more questions.

Thanks to all who reply.

Litahni

 

[nk2a]

search steedspeed or better yet by my stocker for $300

 

[Rush]

http://www.mazdas247.com/forum/showthread.php?t=123663213

However, Focus isn't making his manifolds anymore. But Protephile and Steedspeed are. PM either of them for information on current production runs or any manifolds that they might have sitting on the shelves to sell.

As far as your manifold goes, have you actually SEEN any cracks in it, or are you just going by what the dealer told you? For the most part, you'll wind up with cracks between the runners. If you haven't looked yet, take off your heat shield and take a peek. If you do have cracks between the runners, you can try to find a good welder and have them sealed up. However, that is only a temporary solution -- sooner or later, those welds will give out.

A stock uncracked MSP manifold will sometimes pop up in the For Sale forums here .. but I wouldn't rely on that.

MAM manifolds are excellent. However, direct stock exhaust manifold replacements made by MAM are extremely rare, and you almost never see one up for sale because the owners don't want to part with them.

Upgrading your motor mounts is always an excellent idea. It helps 'keep things together' in the engine bay and also gets rid of that annoying wheel hop that MSPs get when they're launched.

 

[nk2a]

nice post rush > and linked post

 

[Litahni]

Thanks. I had looked at that thread before posting this one. It was old and I wasn't sure if any of those manufacturers were still making the manis. I'll check out Steedspeed. They looked pretty cool.

How about the tranny attachment question? Is that a good preventative measure. After I spend so much money to replace this part, I want to make sure that I do everything I can to prevent it from happening again. You know, an ounce of prevention is worth a pound of cure. Any tips or additional ideas is very welcome.

Thanks all, Litahni

PS Rush, I like your posts. Are you a chic? I am, and I think it's cool to meet other ladies that love cars. Rock on with your bad self.

 

[Rush]

I haven't heard of attaching the manifold to the tranny -- at least, it's not a mod that's publicized very much here. I know that I have my exhaust bolted onto my tranny -- but as far as the manifold itself, it's not. I don't honestly know if that would help or not.

When you are getting your manifold replaced, obviously make sure you get all new gaskets. You might want to think about picking up some different studs, too -- I have the ARP and they're great.

And I forgot in my earlier post .. as far as wrapping the manifold, it's a debated subject. Some people say that it's better, as it keeps the engine bay temperature down -- but then the manifold itself runs a lot hotter. And then some people say that it's better to NOT wrap and let the heat disperse, which leads to a slightly hotter engine bay. Personally, I don't think it matters enough either way. I run my Thunder manifold with no coating or wrapping, but I also have a vent in my hood directly over it that releases most of the hot air.

.. And yep, I'm a girl. Great to see another woman MSP driver on the boards! We're in short supply.

 

[Litahni]

I was just asking about the wrap to temp fix the the cracks til I can get it fixed. I didn't know people did it for other reasons. How about the JB weld idea for a temp fix?

Thanks

 

[nazgul350r]

I would think that wouldnt stand up to the heat and maybe a fire hazard.

 

[Rush]

I was just asking about the wrap to temp fix the the cracks til I can get it fixed. I didn't know people did it for other reasons. How about the JB weld idea for a temp fix?

Thanks

Ehh .. The wrap won't do much to block the leaks. And I wouldn't use the JB weld -- I seriously doubt it would last for more than a few minutes. I tried to use JB weld to attach my BOV to my intercooler hardpipes, and it wouldn't stay on for more than 5 seconds .. so I doubt it's gonna do much on an exhaust manifold.

Honestly, I don't think there's really any 'minor' temporary fixes you can do for a leaky exhaust manifold. You're gonna have to spend some money no matter what you do to get any improvement at all .. So if I were you, I'd just suck it up and drive with the manifold leaking as-is so you don't waste money on temporary fixes that likely won't do much, and start figuring out which replacement manifold you want to buy.

 

[Litahni]

So I'm in the process of pulling off my heatshield. I have it unbolted but I'm not sure what to do about the spark plug looking thing that's sticking out there (PCV?). Is it safe to screw out of there so I can get the shield all the way off? I don't have a manual so I'm a little iffy on that. Speaking of which, where can I get a shop manual for this car?

Also, so far I'm not seeing any cracks in the crotches or anywhere else (LOL). The dealership said it was warped. Does this happen with these manis? How can I tell if it's warped? Maybe run it with the heatshield off and spray a soap solution and look for bubbles?

Told ya, more answers equals more questions.

Thanks to all who reply.

Litahni

 

[dmention7]

That's the 02 sensor. The easiest way to remove it is to get a special socket from an auto parts store. It looks like a normal deep socket except that there is a slot in it to accommodate the wire.... looks like this:

I think it's possible to remove the heat shield without removing the 02 sensor, but it makes it easier.

 

[Rush]

That plug-thingie is your primary oxygen (O2) sensor. It's an expensive part (something like $250 to replace), so be careful with it!

Anyhoo, so long as you're gentle with the O2 sensor, you should be fine. I've had mine off a bunch of times and so long as you only 'hand tighten' the sensor back into the manifold, you won't have any problems. You don't have to use a special tool-thingie, either. Just an adjustable wrench. But like I said -- BE CAREFUL.

One mod to the heat shield that I highly recommend, once you get it off, is chopping off the portion beneath the 'hole' where the O2 sensor sticks out -- so that you can get the heat shield on and off without having to unbolt the O2 sensor. Know what I mean?

Also, the BACK of the heat shield will be a lot of help with diagnosing if you have any manifold leaks. I had HUGE black carbon deposits on the back of my heat shield where my stock manifold had cracks, because the exhaust fumes came poofing out and left all that charming carbon since the car runs so rich. Also, your cracks could be along the back of the manifold where you can't easily see. Make sure the engine is completely cooled, and then try to reach around behind the manifold and see if your hand comes away with nasty-looking black gunk.

I haven't particularly heard of the manifold warping. Cracking? Yes. Warping? No.

 

[laracroft]

Hi-boost also has a direct bolt-on replacement manifold. Check with them. Call TBK Performance in Miami - they have a website and ask for the pricing. I have no idea how much it is. But it shouldn't be more than maybe $600 at most.

I had a local dealer quote me $850 for a stocker a couple years back before I bought my MAM one. I also had a crack in my manifold. It was about 5 inches long and went down to the O2 sensor. This is a common problem.

Here's a picture of mine. Not the greatest quaility since it was with a camera phone. But the crack goes all the way down.

I wouldn't suggest trying to weld it. It's a waste of time and money. And it can't be welded conventionally like a stainless steel one can. Cast iron is different. It's not even a good suggestion.

Hope you get what you need to get the car fixed - but you're still looking at a good chunk of money - no matter how you slice it.

 

[Litahni]

Thanks. I was just getting ready to ask about torque on that. How about torque on the manifold bolts? Maybe they just need torqued down. My dealership pisses me off sometimes. Sucks to live in a small town with so few options.

So, we pulled the heatshield (tin snips worked great to cut that bottom part off, great tip Rush, we didn't even have to pull the O2 sensor). I have some carbon on the upper passenger side corner and nowhere else; clean as a whistle except for that one spot. No cracks, no black gunk off the manifold after feeling all the way around it. That one spot looks like it could be the result of an improperly torqued bolt. What's the torque speck on those bolts? Is it okay to just go 1/2 turn past tight or is it specific torque?

I think I need to find another place to have my car serviced. Those guys at Horizon have pissed me off too many times. Like, telling me they serviced my air filter on my aftermarket CAI, even explaining how they did it because I was concerned about their so-called methods of drying it before re-oiling, then, two weeks later my CEL comes on so that's the first thing I check, and, what do you know, my air filter is disgusting. Liars!!! Now this manifold thing. I think their theivin'? I'm gonna learn to do all this stuff myself. How about that manual? Anybody?

 

[Litahni]

I'm so sad. Just got back from the drag races and wanted to race my car and couldn't because of this dang exhaust leak. Waaaaa!!!

 

[BOOSTR]

Don't gorrilla torque those exhaust manifold bolts as you will break them and then be in a world of s*** if you do not know how to repair that problem.

FWIW, cast iron manifolds are repaired all of the time. What do you think people do with older cars, trucks and equipment with unavailable cast manifolds do, just stop using them because a "tuner" shop isn't offering a high dollar replacement option?

It is also possible to remove that heatsheild without cutting or taking out the sensor. I've done it every time I've taken it off to polish it.

Sounds like that shop was trying to job you. Glad that your manifold was not cracked.

 

[Litahni]

It could be warped though. Do you know of a good way to check that?

You know, that doesn't seem very likely with a cast iron mani, now that I think of it. I think that shop was trying to job me too. I need to find someone else to do my work, or do it myself. How about that manual anyone? Amazon maybe?

 

[BOOSTR]

Pull it off and check it with a straight edge. I doubt its warped though. There is a turbo spec thread that gives you the torque specs for the bolts in the forced induction MSP section.

There are no Haynes or Chilton manuals available as of yet, only the factory service manual and addendum that I know of. But you can find help and information on this site. Most of the basic stuff can be done if you have the tools and desire to get it done.

edit check out this pdf for another possible cause of that cel
Mazdaspeed Protege Wastegate Actuator TSB;
http://www.msprotege.com/members/Cap.../mspwgatsb.pdf