How are other owners dealing with the Noisy VVT/ stretched timing chain issue where their dealers say the noise is normal until after the special warranty extension expires?
Asked by Grizzly1969 Feb 26, 2015 at 04:12 PM about the Mazda CX-7
Question type: Maintenance & Repair
How are other owners dealing with the Noisy VVT/ stretched timing chain issue where
their Mazda dealers say the noise is normal until after the special warranty extension
expires? Then try to sell you a new car because the repairs are so expensive, over
$3000, and they won't warrant the work for any length of time after the repair. This is one
of 3 Special Service programs that should have been recalls issued for 2007-2010
models. This happened after the third, the AC compressor failed. Anyone know if these 3
issues are interrelated? They covered the first, oil blowing through the turbo and blowing
out the exhaust, by installing a "ventilation kit" which appeared to be a cheap fix to this
larger problem of poor design. Of course they discontinued this engine and the cx-7 after
2012.
36 Answers
Isn't it interesting how so many people desired a "timing chain " over a belt? Well, after reading many posts on this forum, I'm beginning to wonder if having the timing belt is much more desirable. Sure, they both cost money to repair, but, changing the timing chain is much more involved, usually tearing down the engine and costing much more money. I thought it was common knowledge years ago that the timing chain was supposed to last the life of the car. The older I get, the more I have to consider who's lifetime are we talking about. So, let me leave you with this thought, you know specifically when your timing belt is changed, it's rubber and likely runs quieter than any chain and if you change it at appropriate intervals, you'll never have a failure. Can you make the same claim about the timing chain? I don't think so.
This is a common issue with Mazda CX-7 due to a faulty tensioner. It keeps the tension on the chain. This was replaced on mine because I heard a rattling sound that sounded like marbles in the motor. Luckily I noticed it right away and it was replaced under warranty. It's not major and once replaced you get tons of mileage. At least as much as a timing belt if not more.
You are lucky, just think if that chain failed at 65-70 miles per hour. Wouldn't you agree that most people who have a timing chain never even think they'll have to ever do anything? If its true that timing chain failures are becoming more commonplace, then, this is a terrible accident waiting to happen to a lot of unsuspecting people. You were extremely fortunate to hear that timing chain, not everyone will be able to discern that. And, why and how often might this happen? It happened to you, so. Its very likely it will happen to other people with the same car. Lighting always strikes place in the same place. As I said in another post, the timing belt is quieter , and you know for sure when it's time to replace. OK, they were able to adjust the tension , that's good. Changing or replacing that chain is a whole lot more involved, correct?
The timing chain in my 2007 CX-7 came off heading home from vacation in Florida...I live in Missouri. I had no idea about this issue. Dealership never mentioned it. Right now I'm looking at $7,200 for a new motor which I am now worried will do the exact same thing. Were there recalls for this? Does anyone know if you can still use the recall?
Andy, first, I'm sorry for your loss, this is devastating news. I don't personally know about recalls, but, this illustrates my point about the benefit of the timing belt design over the timing chain. I think it's much more involved to change the timing chain in labor and complexity. And, since it's mostly out of sight and people just assume that they'll never have a problem with this, it just gets ignored. Worse yet, most people think and sometimes are told that the timing chain is expected to last the life of the car? I'm sure that you didn't have more than 200,000 miles on your 2007 Mazda, did you? As far as I'm concerned, if a car manufacturer tells you that its supposed to last the life of the car, it certainly should last 200,000 miles minimum. Finally, I'm sure that you heard noises and complained to Mazda about this and they ignored you. That's not very good customer service. How do they expect you or anyone else to recommend their vehicles if your treated like that? Still, I would try and persuade them to help you out. I'm sure you got your car serviced regularly?
wmorazamora answered 8 years ago
there is nothing wrong with a timing chain and they will last for more than 200,000 miles before they start stretching the problem is car manufactures are using cheap tensioners like that one used in this car or the ones used in new models Ford F-150 which are made of plastic. if they used the proper tensioner and/or gear along with a chain, timing would never be a problem in any car
Timing chain noise and valve clearance generated noise started at around 100K miles. As for the timing chain, when the car was started up it sounded like a diesel dengine for a few seconds then most of the noise went away as oil pressure builtup. The valve noise can be heard under the hood or with stethoscope. I had both repairs done at the same time as timing chain requires removing valve cover thus giving access to cams. Cost for fixing timing chain issue at a qualified non dealer shop was $1670 which included a precheck of oil pressure for $54. This included change of many related parts: timing chain, valve cover gasket, front seal, VVT Sprocket, chain tensioner, both chain guides, oil pump chain, oil pump chain tensioner. I examined the chain and measured it has stretched by 1.4% equivalent to adding 2 links. This is due to wear at the pin/link interface, the links themselves don't actually stretch measurably. The tensioner(metal), VVT sprocket and guides were ok . The chain guides had little wear, maybe .0003 wear on the surface. Given the age of the car I would recommend only changing the timing chain, valve gasket and front seal. In that case the cost would be $1150 or so. Cost for adjusting valve clearences was $390 when done in conjunction with the timing chain.
I just had my timing chain done at 81k on my 2007 CX-7. I had the turbo replaced at 68k. As Shaka mentioned it sounded like marbles on the motor.
Austin-. How much did it cost you for the new timing chain and tensioner?? And, you had to replace the turbo as well? All at 68,000 miles? What a damn shame!
It was $1,700 for the labor and parts but I bought the extended warranty to 100K thankfully. And yes the turbo was blowing heavy smoke. They replaced it and installed a vent kit I haven't had any issues since with the turbo. This car has taken me for a ride that's for sure.
OK, so, you only paid the deductible..?? If I were you, I would sell the car now while it's in perfect condition. You know there's an urban MYTH that lightening never strikes in the same place,. BUT, the actual truth is, lightening ALWAYS STRIKES in the same place!
After 100,000 miles, it's all on you. I would strongly advise you to dodge this bullet right now. Sorry.
It was only $100 out of my pocket. I still have about a year to pay on it then I plan to sell it at that time. I keep all the paperwork for when that day comes.
For all of you with the same chain noise problem. With about $400 you can buy what is necessary to fix the problem, uncludes the updated version of VVT. I do mechanical jobs on my vehicles and this 2007 Mazda cx7 took me 1.5 days taking my time to do everything right. Chains don't stretch, they simply wear out at the link pins. The reason why chains fail is because the vvt breaks internally making chain to get loose specially ar cold startup. My engine sounde perfect now with no problems.
Edonis, they quoted us 1000 to replace an injector on cylinder 3 and they said it's losing compression and the car is shaky on idle. Is this the same issue and what parts did you buy to fix?
procarloja answered 8 years ago
Hi I am an owner of a 2008 Mazda CX 7 and I am also having the timing belt issue. Belt hasn’t snapped yet but I am worried that it will seens ticking noise has got louder lately. I am located in Ecuador South America, over here mechanics don’t have much knowledge nor experience on this specific issue. So, I will like to know if somebody can provide the list of parts I will need and if there is a tech sheet for this procedure, also if you can suggest an online store that might carry this parts. Any other information regarding this issue will be highly appreciated. Thanks, and cheers.
procarloja-. You mean "timing chain" ,----NOT BELT. If you hear a lot of noise , it's time to have this checked. timing belts are very quiet and are much less expensive to replace.
Depending on how many miles and other wear and tear on your 2008, it might be time to just replace the car. A lot of car dealerships will tell you that the "timing chain" is supposed to last the life of. the car, unfortunately, they frequently don't. If it breaks, your engine is probably ruined. And, there's no immediate way to tell and no regular service interval, remember, they're supposed to last the entire life of the vehicle??? NOT. SO, I usually tell people that when it's time to change the timing chain and it's VERY EXPENSIVE... Its probably time get rid of the car.
My Mazda CX7 caught fire inside while it is parked at Home
https://plus.google.com/events/c630u1to38tcd43o3lalgo37o10?authkey=CJzPq5-Tt7y8ugE
Thanks and this is helpful. If anyone knows where I can buy the timing chain of mazda cx7 of 2008 please assist as mine is making a lot of noise at 69 ooo miles. I live in Zimbabwe and my email address is smatengabadzs@ gmail.com
Below is a link to an online store where you can buy a timing chain for a mazda cx7 2007 and other years too. Plus seals, timing gear & other parts. https://www.carid.com/2010-mazda-cx-7-timing-gears-chains-covers/ https://www.carid.com/2010-mazda-cx-7-timing-gears-chains-covers/
I have replaced the timing chsin in my mazda cx 7 2007 twice already and it is starting to make noise again, including the one factory installed it has already had 3 and replacing it would make number 4. The last mechanic also replaced the brackets that was supposed to help, this model has a serious issue.
I'm glad I found this thread. I was looking at a 2007 cx 7 with 93k miles. The price was right, but not if I have to spend $1000 on top of the purchase price.
Long oil change intervals and timing chains are not a good mix. If you have a timing chain with hundreds of moving parts you really should make oil changes a priority.
I had regular oil changes it is a defect in the model
MarkONEcls answered 5 years ago
Sorry to hijack this thread, but I bought a 2010 model, with 10.000 miles on the clock. Guess it will be the same for this, right?
anyone had isssues with using oil 200klms per 100litres of oil, not having timing belt or chain issues..
BMWworldGuru answered 4 years ago
Technical explanation: There is a lot of misinformation regarding timing chains in modern vehicles. Timing chains used to last and are supposed to last the entire life of the engine even with normal wear and stretching. Problems generally started when variable valve timing were introduced in the late 1990s. The retarding and advancing action of the VVT actuator when the engine is running creates micro impacts on the chain.This happens so many times especially during hard accelerations and over time accelerates the chain and guide wear to a point where the hydraulic chain tentioner upper limit is exceeded. What follows is usually dependent on chance, quality of chain and chain guide design. The chain or guides could break or the chain could jump sprocket position and lose timing synchronization.
I just donated my 2007 CX-7 after learning of a problem with my head gasket and motor. The motor ran, but clearly had issues overheating to a point of failure...there were also all sorts of problems with the traction control and the car couldn't pass basic emissions tests. I only owned the car about 6 months, less than 130 K miles and knew I had a used car lemon. It was like throwing $5 K out the window and the costs to repair was going to be another $5 K...imagine a $10 K CX-7 that was destin to fail again. Donation was my best option...I had to stop the bleeding.
mazda cx 7 knocking bro . but after warm up
Change oil full synthetic and after timing chain if is still making noyse, parts are around 200$ .I have to do same soon.good luck
I have Mazda CX-7 2010 model, stretched timing chain issue just started after a 200.000KM. I have two options, to pay 800 euros for a replacement with original parts or 400 euros with non-original spare parts. The difference is big, so I need your opinion, which ones should I use?
Guru9ZS2MY answered 4 years ago
Here were my current costs of my repair to the "Noisy VVT/ stretched timing chain issue" with OEM parts plus new plugs on 2007 Mazda CX-7 Grand Touring with 120500 miles TECH DESCRIPTION | LABOR PARTS SUBTOTAL 9917 TIMING CHAIN AND GEAR SET R&R 854.68 1131.83 1986.51 TIMING SET [x1.00] 345.68 TIMING COVER GASKET SET [x1.00] 68.25 VALVE COVER GASKET SET [x1.00] 100.39 TIMING SOLENOID [x1.00] 157.38 VARIABLE VALVE TIMING SPROCKET [x1.00] 280.13 NGK PLATINUM PLUG [x4.00] 115.60 OES COIL BOOTS SET COP BOX [x1.00] 64.40