Is there a definitive fix (or one that worked for you) for the CX-7 smoking?

[AboveAverageJoe]

I purchased a 2008 CX-7 that smokes intermittently. I've searched the internet read the threads on the turbo motors smoking. I've learned about the OCC, modified banjo bolts and the PCV fix from Mazda. Is there a fix out there that really works? The more I read, the more confused I become. i have a nice oil leak, could this be the turbo leaking?

[stockms3]

Damn. You could be getting oil from the intake. Check if there is oil in your intake piping. It is possible this is the turbo. A fix would be bnr s1.

[aackthpt]

I can't say I have experience with the cx7 specifically but whatever LOL. The more I've read the more I've become convinced that it's excess crankcase pressure that is the root cause of smoky turbos. I think the banjo bolt is a possible step also, the PCV fix is a really good idea, and I think an OCC solution like the Corksport routing is possibly a good preventative measure because it evacuates the crankcase all the time, including during heavy loads and boosting. That doesn't mean that it 100% fixes smoky turbo but you could try all of those and if nothing works, go to the BNR as suggested. Then you'd just have insurance against the BNR failing (though I think you wouldn't run the banjo bolt with the BNR) and an OCC is never a bad idea anyway.

You should compression test this motor ASAFP, and maybe also do a leakdown. You could try doing a ring soak if the results aren't great, but it might still look bad in which case you've got a lot of work to do before the motor being reliable and long-lasting.

[speed23]

Replace the copper crush washer under the turbo (oil return line) to stop that oil leak.

To fix the oil getting past the seals inside the turbo I suggest the modified banjo bolt to reduce oil flow into the turbo and if you can, raise the idle with accessport. This worked for me, particularly, the banjo bolt.

[AboveAverageJoe]

Originally Posted by aackthpt I can't say I have experience with the cx7 specifically but whatever LOL. The more I've read the more I've become convinced that it's excess crankcase pressure that is the root cause of smoky turbos. I think the banjo bolt is a possible step also, the PCV fix is a really good idea, and I think an OCC solution like the Corksport routing is possibly a good preventative measure because it evacuates the crankcase all the time, including during heavy loads and boosting. That doesn't mean that it 100% fixes smoky turbo but you could try all of those and if nothing works, go to the BNR as suggested. Then you'd just have insurance against the BNR failing (though I think you wouldn't run the banjo bolt with the BNR) and an OCC is never a bad idea anyway. You should compression test this motor ASAFP, and maybe also do a leakdown. You could try doing a ring soak if the results aren't great, but it might still look bad in which case you've got a lot of work to do before the motor being reliable and long-lasting.

My compression check looks like this,

---- Dry Wet
#1 180
#2 180
#3 125 140
#4 180

With the results that good on 1,2 and 4 I didn't bother to wet test them. I will retest 3 again tomorrow to ensure I didn't booger the test up. It was getting too dark to see.
Then I found all of this earlier:

Time for a new chain? Click for video.




Nice plugs, two of them were like this.


I think the turbo may be leaking...

[qtrmile beast]

ok as for the chain its not your chain that is doing that its your tensioner.. as for your oil issue check your PCV maybe even change it and add a catch can with another check valve to to stop crankcase pressure.. also as for the low cylinder you can also have low compression from a leaky injector seal so you might want to do a leak test for that..

[AboveAverageJoe]

Originally Posted by qtrmile beast ok as for the chain its not your chain that is doing that its your tensioner.. as for your oil issue check your PCV maybe even change it and add a catch can with another check valve to to stop crankcase pressure.. also as for the low cylinder you can also have low compression from a leaky injector seal so you might want to do a leak test for that..

Sorry I might be misinterpreting this. Are you telling me that chain is okay and the tensioner is bad?
The PVC, I blew threw the cover and the hose and the nipple on the turbo intake. It flows great both ways forward and backwards. The check valve must be blown. Would you suggest a new factory PCV or something like a Krankvent?

I will leak down test on the injector seal.

Thank you all, I owe you a cold one...

Joe

[aackthpt]

Let's make sure we are speaking the same language. Can you post pictures of what you blew through etc? And by "turbo intake" do you mean the intake manifold that's connected to the head, or the intake attached to the turbo compressor inlet?

See, the PCV system has nothing to do with the intake attached to the turbo compressor inlet. On a ms3, the valve cover does vent to the intake. The PCV down on the block is attached to the intake manifold (which is past the turbo compressor, the intercooler, and the throttle body) through the PCV valve which is essentially only there to provide anti-backflow during boost conditions.

Even if your PCV valve is blown, as long as it is open, if you hooked up the corksport OCC that would fix the problem. Because basically they have you tee the PCV outlet tube and the valve cover outlet together, then connect to the tube on the (pre turbo compressor) intake. They have you cap off the normal PCV sucking port on the intake manifold. Since the pre-turbo intake is always under vacuum, it constantly evacuates the crankcase and the valve cover. It's not necessarily the ideal setup depending what you're going for but it's simple to install and it works.

That #3 compression result sucks, man, big time. Definitely do a leakdown on that cylinder to see if you can identify the loss. If it's through the ring/crankcase then read the following thread: https://mazdaspeeds.org/index.php?th...dventure.3316/ and maybe try the ring cleaning procedure on that cylinder...

I'm far from an expert so if you do all that stuff and #3 still looks bad, I'd pull in some others to advise you the best/easiest way to go.

[AboveAverageJoe]

Originally Posted by aackthpt Let's make sure we are speaking the same language. Can you post pictures of what you blew through etc? And by "turbo intake" do you mean the intake manifold that's connected to the head, or the intake attached to the turbo compressor inlet? I'm wrong, it was the valve cover, the ventilation hose and the fitting on the plastic turbo inlet. I will download a manual so I know what I'm talking about. Sorry, I am old school. I saw the hose coming off of the valve cover and thought that had to be it. Old dog- new tricks. See, the PCV system has nothing to do with the intake attached to the turbo compressor inlet. On a ms3, the valve cover does vent to the intake. The PCV down on the block is attached to the intake manifold (which is past the turbo compressor, the intercooler, and the throttle body) through the PCV valve which is essentially only there to provide anti-backflow during boost conditions. Even if your PCV valve is blown, as long as it is open, if you hooked up the corksport OCC that would fix the problem. Because basically they have you tee the PCV outlet tube and the valve cover outlet together, then connect to the tube on the (pre turbo compressor) intake. They have you cap off the normal PCV sucking port on the intake manifold. Since the pre-turbo intake is always under vacuum, it constantly evacuates the crankcase and the valve cover. It's not necessarily the ideal setup depending what you're going for but it's simple to install and it works. Okay, now I understand. That #3 compression result sucks, man, big time. Definitely do a leakdown on that cylinder to see if you can identify the loss. If it's through the ring/crankcase then read the following thread: https://mazdaspeeds.org/index.php?th...dventure.3316/ and maybe try the ring cleaning procedure on that cylinder... I'm far from an expert so if you do all that stuff and #3 still looks bad, I'd pull in some others to advise you the best/easiest way to go.

aackthpt, I will do a leakdown test and read the thread. I also found and read this one:
Bringing Up Compression Via Engine Soak

I appreciate everyones help

[aackthpt]

Originally Posted by AboveAverageJoe aackthpt, I will do a leakdown test and read the thread. I also found and read this one: Bringing Up Compression Via Engine Soak I appreciate everyones help

Yep, same guy same car same trial, different site. Geoff is one of our OG's.

Good luck!

[AboveAverageJoe]

Today I learned a lesson...
I have decarbonized engines in the past by running a small plastic hose drawing water from a bottle into the intake. So I set everything up on the CX-7 and it smokes a little bit and I turn my head around to look forward and see smoke under the hood and then I see my fence.
c3 b

I shut the car off and was greeted with this mess. The turbo must have spewed half a quart on the engine.
a1
b2
Apparently Mr. Turbo couldn’t handle all that spinning and threw up all over the car and fence. I cleaned it up, bought the GM Top Engine Cleaner and I’m soaking the cylinders like a good boy. I guess I can’t be left alone… I'll let you know the compression and leakdown test as soon as I complete them.. Today was brought to you by the letters, F and the word ME...

[aackthpt]

Links to pictures do not work. Why oh why couldn't you just upload them to the site rather than linking from flickr? All 3rd party photo sites have the AIDS, eventually.

[AboveAverageJoe]

Originally Posted by aackthpt Links to pictures do not work. Why oh why couldn't you just upload them to the site rather than linking from flickr? All 3rd party photo sites have the AIDS, eventually.

Pics fixed, I must have done something wrong. I didn't know I could load to the site rather than host the pictures on a third party. I'll have to do a search. Thanks.

[AboveAverageJoe]

I let the AC Delco Upper Engine and Fuel injector Cleaner sit in cylinder 3 overnight. I modified a turkey baster and sucked the cylinder out this morning. I cranked the car over to blow out the cylinder and let it sit until 4:45 p.m. I did a compression test and with a cold engine, the dry test was 164 pounds. This puts it at 18 pounds less than the rest of the cylinders but with the Mazda recommended variance of 28.5 pounds.

I tried to rent a leak tester but noone seems to have one. I will pick one up tonight and test the cylinder.

As far as my chain video above, is the adjuster bad? Or is it the chain?

Is there a good turbo out there other than the bnr S1? My CX-7 is going to be a daily driver and $899.00 is pretty steep for a 2008 with nothing special on it.

Thanks again,

Joe

[aackthpt]

Good work, another win for the cleaner. I tell you what the dude that suggested that is THE MAN.

I can't help you too much with the chain but I'm pretty sure they are replaced together so there's really only one question - is it too much play.

As for the turbo, see if you can get a cheap aftermarket stock turbo from a scrap yard. Have you looked at Rock Auto? If they list turbos it might even be worth taking a flyer on one of your trying to keep the project that cheap.

Sent from my Moto G (4) using Tapatalk

[AboveAverageJoe]

After watching what it takes to do the chain, I'm not ready for that job without supervision from someone who knows how. Is there someone out there that will do that or do I have to take it to the dealer?

[aackthpt]

Originally Posted by AboveAverageJoe After watching what it takes to do the chain, I'm not ready for that job without supervision from someone who knows how. Is there someone out there that will do that or do I have to take it to the dealer?

I take it you concluded it needs to be done? Have you checked out the cost of the complete kit, and are you planning to buy or build the tools?

There are several people around who may or may not be willing to help if I had to guess. One of those is not on the forums anymore. If you have a grill and beer you can probably get help easily. I'll PM you on it in the next couple days to help you get start planning a work day.

[AboveAverageJoe]

Originally Posted by aackthpt I take it you concluded it needs to be done? Have you checked out the cost of the complete kit, and are you planning to buy or build the tools? There are several people around who may or may not be willing to help if I had to guess. One of those is not on the forums anymore. If you have a grill and beer you can probably get help easily. I'll PM you on it in the next couple days to help you get start planning a work day.

Grill and Beer? I can do that as well as spin wrenches and I'm willing to do work on others cars also. Tools? If the tools are expensive, I'd rather rent from someone here who has them. I'm basing this on the fact I haven't done my due diligence on part and tool cost, I will be doing that after dinner.

Thank you again!

Joe

[AboveAverageJoe]

I found a thread on the site that has a part list, I contact the Mazda dealers near me to get a current price on the parts.

List of parts.





Thread link
Timing chain/VVT replacement parts list

[aackthpt]

It doesn't have to be that difficult. Mazda OEM VVT Replacement Kit Mazdaspeed 3 / Mazdaspeed 6

You can get the parts including the tools easily this way as well, if no one with the tools wants to come over/lend.

[qtrmile beast]

ok if you are somewhat mechanically inclined you can do the TENSIONER which is the problem not the chain..

SIMPLE breakdown:

REMOVE assy belt

REMOVE pulley from timing cover

REMOVE crank pulley and crank sensor

REMOVE timing cover(i believe 13 bolts) all i believe are 8mm and 1 i believe 13mm.

REMOVE exhaust sprocket (15/16)

REMOVE crank pulley 22 mm i believe


These directions are how to get the timing cover off

The best way to do this is to find TDC before you take anything apart... If you dont your going to add another few hours to your job.

[nindoja]

You're going to want to follow @rokusek's How-to VVT thread (HOW-TO VVT) for the step by step. @qtrmile beast; has some of the steps, but it's very important you get the timing tools and use them properly otherwise you'll end up major failure.

[qtrmile beast]

........

[AboveAverageJoe]

Update on the chain/VVT. Just stick with me through the story, I need the backup to make a point.

I wanted to understand how the VVT worked so I started watching videos on the subject. I ran across this video, that's what mine sounds like:
https://www.youtube.com/watch?v=coZLPXJ-PhA

Video of VVT for us luddites who didn't understand it.
https://www.youtube.com/watch?v=qZbaDZPrl_0

After educating myself about the VVT and VVT solenoid work and how oil of the wrong weight or dirty oil can cause problems, I removed the solenoid, cleaned it and changed the oil and oil filter. The old oil was pretty dirty and the filter was heavy for as small as it is. I put in Mobil Super Synthetic 5w30 and started the car, I still had the "nack, nack, nack" sound for 5 seconds at startup so, I let the car run for 15 minutes and let it sit sit for two hours. The sound was reduced to about two seconds at the 2 hour start up. I went back after 4 hours of sitting then 6 hours and then overnight. The sound has been reduced to one second long which is still too long in my book but the oil coming out of the turbo and the exhaust smoking at idle has been reduced. I read that Miatas and even other makes of cars have a screen where the solenoid mounts and it should be cleaned also. Does the 2.3 Turbo have such a screen?

I plan on letting the car idle from time to time this week to see if the sound stops. If it doesn't, I'm ordering the chain kit and tools that aackthpt posted.

[AboveAverageJoe]

Guess what, there is a filter. I'll take some pictures after I pull the valve cover off.
CCI_000032 (1)

[aackthpt]

Originally Posted by AboveAverageJoe Video of VVT for us luddites who didn't understand it. https://www.youtube.com/watch?v=qZbaDZPrl_0

Wow that's fantastic. That guy's like a commoner version of Sir Jackie Stewart.

[AboveAverageJoe]

Excuse the crummy cellphone pics.
The filter is under the cap that is circled in the pic. . I couldn't remove the the cap and I didn't want to use any heat on the plastic filter so I pulled the whole cam bracket out.
sa

You can see the filter inside the cam bracket, I had to carefully pop it out with a small bent screwdriver.
sd

You can see the filter is dirty. I washed the bracket and filter with brake cleaner. I cranked the starter for a sec to blow anything out of the oil galley that may have been trapped by the filter.
sc
sb

I reassembled everything and started the car, the nack sound was back and lasted for about 4-5 seconds. I know that's because there wasn't any oil in the filter, solenoid and bracket. I'll wait 4 hours and try it again. The idle did drop down and smoothed out quickly. I hope this cured it.

[aackthpt]

Wow that's pretty fantastic. Have to wonder if there have been a lot of replacements that could just have been cleaning jobs, if it works. If not I guess you're going to have to full-up fix it. Wish you luck here.

[AboveAverageJoe]

Originally Posted by aackthpt Wow that's pretty fantastic. Have to wonder if there have been a lot of replacements that could just have been cleaning jobs, if it works. If not I guess you're going to have to full-up fix it. Wish you luck here.

I've been reading some more, the solenoid can cause problems too. I believe if you catch it soon enough a good cleaning could save some engines. I wonder if the screen is actually on a maintenance schedule. I think my VVT Actuator is toast from running too long like this. I just started the car at 9:47 p.m. and it's still making the noise. I'll try tomorrow morning, if it rattles, I'm done playing around. I'll be ordering the kit and tools.

[AboveAverageJoe]

Parts and tools ordered, i will have borrow or build the crank pulley spanner to hold it in place.

[nindoja]

Originally Posted by AboveAverageJoe Parts and tools ordered, i will have borrow or build the crank pulley spanner to hold it in place.

No need. The FSM calls for using an M6x1.0 bolt in the hole in the block and the timing cover. Go to a hardware store and buy a Grade 8 or higher M6 bolt and torque it down in there. No need to super tighten the bolt (don't want to snap the bolt in the timing cover, but enough to hold it in place).

[AboveAverageJoe]

Parts made it in.

[AboveAverageJoe]

Okay everyone I believe I have a huge problem. In order to put my timing plate in place, I have to rotate my crank off of top dead center. It also looks like my VVT is the wrong position compared to pictures of other VVTs by other members.

Here's a picture of a VVT in Rokusek's how to VVT thread. HOW-TO VVT

[IMG]2606ark

My VVT position and my balancer position (two teeth off) when the cams are timed with a plate. The timing mark is the tooth in the red circle.
[IMG]VVT

XCrank

Do I just continue with the disassembly and retime the crank back at TDC then put the crank pulley on the correct tooth and then put the VVT in the same position or as close to as I can to Rokuisek's in the photo?

Thank you in advance, Joe

[nindoja]

Originally Posted by AboveAverageJoe Okay everyone I believe I have a huge problem. In order to put my timing plate in place, I have to rotate my crank off of top dead center. It also looks like my VVT is the wrong position compared to pictures of other VVTs by other members. Here's a picture of a VVT in Rokusek's how to VVT thread. HOW-TO VVT [IMG]2606ark My VVT position and my balancer position (two teeth off) when the cams are timed with a plate. The timing mark is the tooth in the red circle. [IMG]VVT XCrank Do I just continue with the disassembly and retime the crank back at TDC then put the crank pulley on the correct tooth and then put the VVT in the same position or as close to as I can to Rokuisek's in the photo? Thank you in advance, Joe

The orientation of the cam sprockets do not matter. All that matters is that the cams are in time with the crank when at cylinder 1 top dead center. You do need the crank oriented properly, tooth wise, but cam sprockets can be attached whichever way you want.

[AboveAverageJoe]

I completed the CX-7 not long after the last post. I installed the following parts,

Water pump
Thermostat
Battery
Rear brakes
Control arms and ball joints, Thank you Mazda recall!
Spark plugs
Rebuilt Turbo
Timing chain
VVT - Variable Valve timing servo and solenoid
Serpentine belt
Cabin air filter
Used but repainted bumper
I had Air Bag lights on but those were cured by cleaning the contacts under the seats and having the PAD light repaired.

I've driven fast cars and have raced at Detroit Dragway when it was open. The CX-7 and the Mazda 6 that I sold are pretty impressive. My wife wants me to sell the CX-7 too, but so far I have resisted.

Thanks to all of you on the board for your info.