Just got the new 05' MS MX-5 home, first impressions & concerns
 

So as some of you may have read in my meet & greet I found an 2005 mazdaspeed miata that has ~75,000mi

I managed to negotiate a price of 8,800$ and drove it home yesterday. It did fantastic on the ride home (which was 5.5 hours) the aftermarket boost gauge picks up to ~8 psi really quick and holds it there well without trickling down.

I noticed when I got there that the intercooler was way bigger than the stock MSM intercooler...which obviously is a plus...seller said thats how he bought it.
https://www.miataturbo.net/attachmen...ine=1430761072

I also noticed a low end grunt to the exhaust note thats not loud, but its there and its pretty tame...When I asked him about this he just said " I dunno, its just mazdaspeed exhaust" ....I then saw that there is a " Flyin' Miata" logo etched on the tailpipe...kept my mouth shut
https://www.miataturbo.net/attachmen...ine=1430761072

So after I got home the car got a wash and wax, polished the headlight lenses because they were very yellow...then I charged the A/C unit because it was blowing hot air (it was low on Freon)...

then I was anxious to take a look and see what exhaust was installed on this thing.... I'm still not sure if this is just a flying miata muffler or a full exhaust system... here is some pictures.

https://www.miataturbo.net/attachmen...ine=1430761072
https://www.miataturbo.net/attachmen...ine=1430761072
https://www.miataturbo.net/attachmen...ine=1430761072

Now here comes a newbie question:
there is a sound when I start the car...obviously coming from the turbo because it sounds like a weed-eater, whispy, kind of like when you take a jump rope and spin it really fast or something... once you rev it up and take off it speeds up the whispy sound fades, and it goes away until you start the car again...

is this just the turbo not getting oil pressure or something from setting?...this is my first turbo car sorry

That looks to be a full FM exhaust.

Your noise is probably an exhaust leak. Either at the manifold to head, manifold to turbo, or downpipe to midpipe.

Thanks Concealer!

I hope being driven 6 hours with the exhaust leak didn't harm anything. wonder if it could cause inaccurate O2 sensor readings and run lean.

forgot to mention that there was a check engine light that was on when I test drove it, it went away after 5 miles...comes back on every now and then.

he said that he got it checked and It was somthing to do with an O2 sensor...anyways I'm going to run by an autoparts store and get the code for that light when I see it.

take the heat shield off the turbo, look at where the exhaust manifold mates to the head, you will see black marks on the end nearest the firewall. The nuts tend to loosen up.
Exhaust Leak **pics** apparently common

There's the problem and the fix all in one, most likely.

Yup.

Between the intercooler, exhaust, and boost controller, I'd expect it to have the entire little enchilada package on it. Intercooler looks to be about the right size. Does it have their intake, throttle body, and downpipe on it? It's definitely FM exhaust, I don't think anything but FM's mid pipe bolts on to that MSM exhaust.

You are correct, though the midpipe does mate up to the stock down pipe.

Really, thanks for the prompt responses guys. I'm kicking myself for not looking up the issue sooner and bummed I may have caused some damage.

I did get the code pulled @ O'Riley today: code p0134

definition: heated O2 sensor (bank 1) / lack of activity

Possible causes:
check for leaks in the air induction system
check for leaks in the exhaust manifold or exhaust pipe
H2Os connector is damaged (check pins for damage and moisture)
PCM has failed

He said the same one came up, but for bank 2....these are both of the O2 sensors..

UPDATE: Just checked under the hood! there in plan sight is the burnt spot on the last runner/side of the head were manifold is leaking...about to try and tighten it right now after it cools down

Yeah that won't fix anything. Needs to come off and be milled flat, or it'll just leak again.

:facepalm:

Likely chance it just needs a new gasket and cranked down with better fasteners, honestly. Give that a shot. Be mindful of the oil return pipe if/when you do this.

1) I've never seen a manifold with a MLS gasket "just" need a new gasket after developing a leak
2) After going through all the pain and agony of pulling the OEM msm hot parts, and to not surface the mani, is beyond dumb.

The pain and agony of a 45 minute job? :bowrofl:

Mine didn't leak any more after replacing the gasket and nuts. It was leaking because the nuts had literally backed off enough that 3 of them could be spun off with my fingers.

I'm just saying take a look before assuming worst case scenario and causing MUCH more work for yourself.

It takes you 45 minutes to completely take apart the hot parts on an msm? Are you faeflora? surfacing the mani is $40 bux and like 1 hour.
It's what evs

No. Why are you completely taking the hot parts apart on an MSM to do a manifold-to-head gasket?


I agree: If you're taking the entire thing apart for some reason, get the shit resurfaced.

Looks like you got lucky with the MSM "Enchilada" bonus. Once you get that exhaust leak figured out it looks like you are going to really enjoy this car.

Ok, so I'm running out to get a can of PBblaster and Ill get in there and see if the nuts are actually loose on the studs...thats about all I can do today because I can't get to my shop until this weekend

OEM replacment gasket? or a different material?

not ruling out that it needs to be milled/re-surfaced but I agree that the easiest fix should be attempted first. I have no problem taking it off again, it'll be easier and quicker the second time if needed

Searching right now for threads about re-surfacing the manifold, is it the type of imperfection that can be fixed with a good file and a flat T-square? or is it such a miniscule imperfection that it needs to be milled on a precision machine?

guess thats what Ill find out when I actually see it

A lot of us MSM owners just periodically re-tighten the manifold nuts. Unless it's leaking really bad there's no reason to pull the manifold. The job itself is quite involved, basically the manifold won't come off until you remove a lot of things. I would save it for a winter project or something. One of those "while your in there" sort of things you can do is replace other gaskets and consider porting the wastegate for better boost control. I just removed my turbo a few weeks ago and it took me about a weekend to do so.

Alright, thanks again guys for your response.

Anyways, I managed to get down to the manifold today, and the 2 nuts on the last runner (last 2 nuts towards the firewall) were loose, if they were not so rusty, they would have been able to turn loose by hand.

I tightened them, and put it all back together. Granted thats all I can do because I'm not at my house with all of my tools.

the sound is still there.

I'm trying to upload a video via photobucket.

One thing I noticed is that the sound is only audible when the throttle is touched. I realized this may just be a intake tract related boost leak, because when the car is just idle there is no clicky-whispy weed-eater noise. although the burnt mark is still there on the side of the head, I noticed that all of the hoses are pretty hard and the stock spring clamps SUCK ASS.

another thing to support this idea is that one of the previous owners fitted an aftermarket intercooler, which IIRC means that the stock piping might have been hacked up and a seal may have been compromised.

Very possible. Which would also potentially throw o2 codes.

Make a boost leak tester and see what's up.