Engine Nosie

[dar_vedar]

HI All

for the past few days I have been getting a slapping noise (like a chain slapping noise) from the engine bay on cold start ups. the noise disappears in under 2 seconds.
anyone else had a similar issue??

[Rayd]

Your VVT needs to be replaced

[dar_vedar]

@rayd thank for the quick reply mate. just curious to know what will happen if delayed replacing it.

[Reedy]

How many k's have you done? @Jeev 's timing chain came loose after about 200 000k's and started doing exactly this.

[dar_vedar]

@Reedy i have done 97,000kms. But the car also get driven hard sometimes.
because if i am chaning the vvt i will also be changing the timming chain and tensioner

[Harry LuvzDrift]

If u love ur Mps DO IT NOW lol

[dar_vedar]

i want to but just strapped for cash atm becasue this was a sudden unexpectant expense
is it fine to run it like this for about a week or so?

[Harry LuvzDrift]

Tbh you will better off asking this question from a mechanic. Afaik it will lower engine performance n unburnt oil n emissions. So drive like a granny now.

[Reedy]

Jeev drove his car like that for 6 months before he got it fixed. I can't recommend it but if you have the same problem, it isn't an imminent explosion waiting to happen as long as you're gentle with it. Which Jeev was not.

[dar_vedar]

i was thinking it could be something to do with oil pressure not getting up fast enough. becasue some old cars used to do this as well.

- - - Updated - - -

oh n anyone know how much it costs to fix??

[Jeev]

The 2 noises you hear are:

1) The timing chain being loose and taking up tension on startup.

And possibly:

2) When you first start the car; the chain tension (Lack of) causes the timing chain to leave the sprocket on the trailing side and slap the inside of the rocker cover. You can check this by removing the oil filler cap and sticking your finger in there. The top of the chain is right near the cap.

My car started having issues after a 120,000km oil change. I made the mistake of using flush (ALWAYS flush with low grade engine oil, not oil flush.), which dislodged some contaminants, blocked the tensioner oil feed and caused my chain tensioner to seize. In the end I had the VVT Actuator, Chain Tensioner and Chain replaced. the service was $1700 including all parts, labour, filters and oil.

Although it was doing it for some 10,000kms, I wouldn't recommend leaving it for too long. If the chain has stretched enough, or the tensioner has enough throw then you can cause some issues to your timing system..... Not preferable in an interference engine. Chain skips a tooth and you might be looking at a rebuild

[dar_vedar]

thanks for the input guys. i spoke to mazda and they immedietly told me it was the vvt. they quoted me $1200 over the phone for vvt, chain and chain tensioner.
will probably get it done in 2 weeks becasue their next avialbe date is after 18/03.

[Rayd]

thanks for the input guys. i spoke to mazda and they immedietly told me it was the vvt. they quoted me $1200 over the phone for vvt, chain and chain tensioner.
will probably get it done in 2 weeks becasue their next avialbe date is after 18/03.

sounds about right... hope its a nice quick fix for ya

[mymps11]

Im not convinced that all u guys having the vvt units replaced really need too, unless of course the chain is loose and slapping. An example i have an nissan pulsar sss sr20de engine which runs a chain and ever since ive owned it its had a slight rattle that last no longer then 2 secs on start up. Now my brand new 2012.mps does the same it has a mere 12,000ks and has done it since new. A 2sec rattle on startup is normal, oil pressure isnt instantanious, almost but not quiet. This is just my opinion
Mitch

[Rayd]

Im not convinced that all u guys having the vvt units replaced really need too, unless of course the chain is loose and slapping. An example i have an nissan pulsar sss sr20de engine which runs a chain and ever since ive owned it its had a slight rattle that last no longer then 2 secs on start up. Now my brand new 2012.mps does the same it has a mere 12,000ks and has done it since new. A 2sec rattle on startup is normal, oil pressure isnt instantanious, almost but not quiet. This is just my opinion
Mitch

In before zzb

[bullet dust]

As a Mazda tech for the last 20 years as well as workshop manager I can assure you, almost every L3T engine has this noise on startup for no more than 2 secs. Provided the noise doesn't last longer than roughly 2 seconds it is just the VVT actuator building up oil pressure - It's more noticeable on the L3T engines as opposed to the L3 or LF engines as the L3T has the high pressure fuel pump running off the exhaust cam (the cam with the VVT actuator) which places additional load on the VVT actuator itself.

In the cases that I have replaced the VVT actuator on the L3T engine (and I have done a few), the noise lasts far longer than 2 seconds when the engine is cold.

Timing chains can be an issue on the L3T engine, however I have never seen one fail personally. When the timing chain stretches the noise lasts far longer than 2 seconds and is a far louder noise than the VVT actuator issue. The only time I have had to replace a timing chain was on a Mazda 6 twin cam common rail diesel and there was no doubt the chain had stretched due to the constant rattle.

All things considered, with the exception of a very small amount of VVT actuators and some turbochargers, the L3T engine is a very reliable and rugged unit - Especially considering it's high boost pressure from the factory, it's rare direct injection system and it's high standard power output - Realistically speaking, in my experience, the only thing that kills L3T engines is idiot owners that don't change the oil at the recommended intervals or use cheap oil (Mazda Australia only recommends Mazda Premium fully synthetic oil for the L3T engine, not semi-synthetic Magnatec).

For the record, my pristine BK M3 MPS rattles for 2 seconds on startup after it's been sitting - And I'm not the slightest bit concerned as I know it's normal. And with oil changes every 5,000klms, at 130,000klms my car runs sweet.

It is nice to see a group of enthusiests that are fanatical about Mazda's finest car since the FD RX-7.

[mymps11]

Thankyou, everyone take note of the above post if they want solid advice, this backs my opinion 1
100%. If i may high jack this thread for a moment...." bullet dust" what would u say about an mps with 12,000kms blowing a quick white thin screen of smoke imediately on cold start up, but never any other time? Is it a cause for concern. When it does it u can smell its oil, then straight after u can smell fuel from cold start.

Mitch

[bullet dust]

Mymps11,

I have never seen an oil burning issue on a 12,000k old L3T engine, never. What is your oil level set at? It isn't too high is it? What grade oil is in the car? Is the engine oil level actually dropping between services?

Generally, when the turbo goes you know about it as the smoke is emitted from the tailpipe literally in plumes and they tend to smoke more when they're hot as opposed to cold.

I have seen valve guides go on an L3T engine before under the warranty period of the engine, however it was in the early days of the L3T engine and the car had done far more than 12,000klms - I've never seen an issue on a correctly serviced engine since.

If you're concerned I recommend getting a reputable dealer to check the issue out - If anything, just to set your mind at ease. However, don't stress, if there is an oil consumption/burning issue there you have 3 years/100,000klms for it to get worse and get repaired under warranty. And believe me, if there is an issue there, it will get worse well within that timeframe.

[dar_vedar]

@bullet dust thanks heaps for the input. either way my car is hitting the 100k mark so im replacing the timming chain, tensioners, vvt and the serpentine seciton. hopefully this reduces the noise and the new chain makes my engine like new.

[bullet dust]

It's up to you dar_vedar, don't forget to replace the diamond washers and the crank pulley bolt (the bolt is a one use stretch bolt).