Cold Start internal engine rattle, looking for advice

Technical Area Engine, Transmission, Exhaust etc
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  1. My model of MX-5 is: MK3.5 1.8se
  2. I’m based near: Bristol
  3. I’m looking for technical help or recommendations on: Engine Rattles

Hello,

Just looking for some more opinions on this rattle from my 2009 MX5, it rattles on cold starts and has done for about 14k miles of pretty intense driving, doesn’t seem to be getting worse but it’s driving me nuts, i’ve had the timing chain replaced and it shouldn’t be rod bearings as it’s been so many miles since it started, no-one seems to be able to get to the bottom of it and i’m hoping someone can help me finally solve this riddle.

Thanks,

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Not on mx5’s but in my experience that sounds like a hydraulic lifter. They are filled with oil and if one or more has no oil in it then it will rattle when you first start the car, within seconds oil pressure fills them up and it stops. I had a mitsubishi fto years ago and the non mivec ones were very prone to this. The fix was updated lifters with larger oil holes. Despite being annoying I don’t think it’s anything to worry about.

Hopefully someone else has direct mx5 experience of the same issue. :+1:

3

Solid lifters on the NC.

4

Sounded like lifter, didn’t know they were solid on these so good to know :+1:. As it ticks cold for a very short time it certainly does seem hydraulic/oil pressure related.

5

Remove serpentine belt at front of engine, restart engine for 20 seconds, if noise is gone then it’s the tensioner and or idler pulley that needs replacing :nerd_face:

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I’ll give that a go on saturday, i’ll see if it changes anything.

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It’s the usual bottom end rattle i’m afraid, it needs to come out and be fully rebuilt with some new parts.
It’s either been remapped and run on the wrong fuel or has been burning oil and eventually run without enough in causing the damage.

http://www.duratecnc.co.uk/?p=146

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It doesn’t consume any oil nor has it got majorly worse after 16k miles of autocross, b road thrashing and motorways, I’ve never heard of bad bearings lasting that long or that much abuse?

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Ok so you have heard of an engine going 16k miles with rod knock, if it isn’t getting worse why should i take your word for it, a rod knock is due to a faulty bearing with a gap where there really isn’t supposed to be a gap, this doesn’t typically have long for this world (and that’s according to performance link who build these engines as well), let alone 16k miles of hard driving.

I don’t just have £3.5k laying around for a spare engine/rebuild nor will the garage i bought it from accept any liability so your response comes off as incredibly condescending rather than actually helpful.

At what point would it be unreasonable for rod knock to last this long, 20k, 30k, 50k, can you show me anywhere where these engines last 16k miles with a knocking bearing , i won’t just blindly accept something with no evidence to the contrary, apart from the word of a angry forum user who rather than actually help just insults me when i question something which goes against everything i know and have been told about how rod bearings fail.

Not to mention the fact it’s completely standard and burns absolutely no oil, not a spec of it since 97k to 102k.

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RUDE !!

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Pure fantasy.
You have zero experience and no knowledge of these matters. If you did you wouldn’t be repeatedly asking around the internet and would have fixed it by now.
An engine does not even cost half that amount. This is what I do for a living and have done for decades, i’m not some amateur or armchair expert. I’m giving you free professional advice and you’ve taken no notice of it.
You bought a broken car from a dealer when you shouldn’t have done. I can only assume you thought you knew better, that it would be an easy fix and you bought it on that basis with an invoice worded accordingly.
If anyone else had unwittingly bought it like that they would be well within their legal rights to take it back and would have done, it’s black and white, it’s easily proven.

There is only one undisputable fact here and that is one or more rod bearings are worn. That in itself is not black and white, there are many degrees of wear.
Why this needs a new thread every few months is beyond me, it’s total waste of forum space and everyone’s time.

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Ok now you are making stuff up, the car was bought with no indication of a rattle 1 year ago, 2 months passed and it started rattling on startup, no change in oil level, no change in anything, took it to the garage who claimed they couldn’t hear the noise on multiple occasions (so obviously not so “black and white, it’s easily proven”) and refused to take it back.

This was the advert from the garage i bought it from, absolutely no mention of any issues with the car.

Advert Text: OAKLANDS ARE PLEASED TO OFFER THIS WELL CARED FOR MAZDA MX-5 … Finished In Brilliant Black With Complementing Black Cloth Upholstery. Specification Includes - Upgraded Pioneer Radio With BLUETOOTH Phone System, AUX Input, USB Port & Bluetooth Audio, Driver & Passenger Airbags, Remote Central Locking With Immobiliser, 5 Speed Manual Gearbox, On Board Computer, Electric Mirrors & Windows, Cup Holders, Black Cloth Manual Convertible Roof, Wind Guard, Rollover Bars, 16 Inch 5 Double Spoke Alloy Wheels & Full SE Body Styling. This Two Owner From New Mazda MX-5 Has Covered 86,734 Miles & Comes With Service History (10 x Services, Last Serviced At 78,439 Miles). Fully HPI Checked & Clear. SAT NAV Users Our Postcode Is BS21 6TH. Please Call To Arrange A Time To Come And View. Finance Available, Subject To Status. Phone lines open until 10pm. WhatsApp - 07375 989848 | Email - info@oaklandsautomotive.co.uk | Telephone - 01934 550055, Upgrades - Black Cloth soft top, Cloth- Black, 2 seats, Metallic Black, 1 owner, FINANCE AVAILABLE FROM 9.9% APR | WARRANTY WISE APPROVED DEALER | LIFESHINE PAINT PROTECTION |, £4,249

I bought what i was sure was a 100% working Mazda MX5 with minor wear and tear, no engine issues, and when i did think engine issues, well i couldn’t do ■■■■ as they refused to do anything about it anyway (well they did but they offered me £1250 to buy the car back of me which is unreaonable).

And as far as i’m aware just throwing a new engine in these cars is a bad idea if you want it to last, you need a new engine, about £1k from what i’ve seen on facebook of people breaking these cars + £1k ish labour to remove and reinstall the new engine. However as you yourself are well aware these engines are very prone to issues with oil burning so it doesn’t make sense not to rebuild the engine outside of the car rather than chuck in an engine with an unknown history only for it to blow it’s piston rings and then be left either buying another questionable engine or taking that engine out for a rebuild anyway.

I’ve taken your professional advice and i’ve been able to do nothing with it because the garage refuses liability and court wait times are in the years and i’ll likely need to actively dismantle my old engine beforehand (which is something i don’t have the money nor time to do) or get a garage willing to sign courtdocuments (which is incredibly hard to find). My exact thought was if it’s rod bearing issues then i’ll run it till it inevitably explodes and then when it does i’ll take them to court with concrete evidence, but it hasn’t over a substantial period of miles and time (rattle started 87k, now on 102k).

You are just making up a story in your head to justify being extremely rude on a forum where i’m asking for help, people all give conflicting information on what it is (other engine builders as well) so i’m just stuck in the middle being berated because i didn’t blindly follow just your advice.

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@Zdos123 Have you tried this yet to at least rule it out as the cause?

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I’m trying it when i get back in this afternoon hopefully

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I mentioned Invoice, you give me advert, one is not the other.
An invoice would be good evidence in court, an advert would not be.
I have on occasion done written reports for people who have been ripped off, they then sent them to the dealer to get their money back. I’ve never had to stand up in court yet to give evidence, but I would if it were necessary.
You haven’t taken any of my advice at all, if you have you haven’t reported back with what you found. All you’ve done is defend yourself for some reason.

What is the reg No.?

It is black and white, your recent video (which has taken 8 months for you to come up with) shows this. You were also given this belt tensioner advice back then too and are only just doing it now.
You’re right to say it would be a bad idea to put another engine in (without inspecting/overhauling it internally), but then your existing engine could be diagnosed and repaired very easily and not costing anywhere near what you’re suggesting.

It’s possible that you never noticed the noise initially. If it did start within the warranty period then they 're legally bound to sort it out or give you your money back. A written report from a specialist would have been leverage had they declined.

There are no end of places to go for free legal advice, two forums I can think of and Citizens advice, for some reason you never followed the right path and don’t stand much of a chance now, 6months on.

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For you and anyone else in this thread, i have taken the belt off and started it twice now where it would have 100% rattled prior and it’s had absolutely no noises whatsoever, i’m going to leave it 24 hours till i get home from work to make sure it’s well and truely at it’s work case scenario and try to start it again tommorow, if there is still no noise then i’m going to replace the idler pulley, tensioner and belt.

Also in regards to not trying the belt test earlier, i did however i could only take it off once and the noise didn’t happen, however the noise was much more intermittent when i did it so it not doing it once could very well just have been happen-chance. I have managed to time this test more convientnly so i’ve had the entirety of today and then 24 hours until tommorow to test it.

I also did try several garages (4 to be precise) and none of them were willing to put any sort of legally binding statement without taking further diagnostic works, i’m don’t run a mecahnic nor am i lawyer so i only had there word to go on.

And none of this changes the fact that you have been incredibly rude for absolutely no reason, if you are only going to berate me what’s the point in even responding.

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What is the reg No.?

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Why is it important to you?

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It’s not important to me, it’s important to you.

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Did you get my message???