Miata Rod Knock

[035577]

@Carsonplmtff no its not.

[Premixyz]

Not a ford engine --> ford used mazda engines even back in the 1.3ltr festiva (a true powerhouse) - sorry yours had SIDS but these things often go for 300k + miles. I just took apart one with 166,000 and you can still see hone marks on the cylinder walls!

[santawi]

check with stethoscope to pin down the noise. The timing chain tensioner and guides are worn out

[guitarmas23]

My 2002 Miata made the exact same noise. I also thought it was a rod knock and so did all of the mechanics where I took it. It turned out that the water pump was bad. I had the water pump replaced and the noise is gone! :)

[DontFilmMeBro]

was it a rod bearing, or a crank bearing? or was it the camshaft bearing?

[ImportsAreBetter]

hahaha ford escort motor

[wheresmymoney]

My knocking was one loose spark plug. I could feel it with my hand on the top of the plug wire #1.

Tightened it properly and it went away. Yours sound a bit different. I hear yours after it gets a certain higher rpm. Mine was at idle and tapped faster with the rpms.

[vtluu]

Started getting the same thing in my newly built race engine (in my '99 ITS Miata) yesterday. The telling thing was that the rattle went away (only) when I pulled the #4 plug wire. Now I have to tear down the engine all over again. :-(

[ejavaidm]

aaddaamm03

How did you fix the rod knock problem?

[Nettikturbo]

Are you sure its not a lifter sound?

[gforce23]

Hey Adam, I just had the same noise in my '92 Miata.. the top/head seems just fine. Even replacing the oil didn't help. If you replaced the bearings, may I know how much did it cost you? The local service guy advised me to go for an engine swap which I feel isn't really necessary.

[yoitsyodaddy18]

HLA noise is a ticking noise not a solid noise..... Charlesdhall u have a diff problem cause thats not a HLA lol

[swissarmour]

big motor? did u go the 5.0 way? my cars got that same problem along with the bad journal, now real hard to time back, what is the spun rod bearing? does this affect acceleration or is it merely the hla noise

[1skiinIan]

it will effect performance if you don't get it fixed soon, and can do some pretty bad engine damage

[charlesdhall]

Good news it is the HLA's. One or more have collapsed and you are hearing the sound of the overhead cam lobe slapping into the HLA's. Using a thinner oil (5w30 synthetic) can even correct the problem for some cars. If not remove the valve cover and check the gap between the cam lobe and the HLA's is not more than 0.015 inch. If it's more than 0.015 inch go to the KIA dealer and purchase a set for the 1994-1997 Sephia GS as they use the same engine and you save big bucks. Hope this helps. Charles

[AAddaamm03]

Thanks for the good news. Too bad it was a spun rod bearing and a scored crankshaft journal instead.

[charlesdhall]

Man, sorry to hear that. Shows what I know. But it does sound the same as mine did with the HLA problem I mentioned.

[heatherandpaul2]

@charlesdhall hey charles, I have a 2008 Miata with the 2.0. Its starting to make this same noise also. Do the newer engines have this same problem with the thin oil? 25K miles. I took it to Mazda and they "did not hear anything." It does it at about 1800 to 200 rpm inder light load. Thanks for any information you may have.

[AAddaamm03]

It was a spun bearing.

[BATTAOUSAI]

.......being that the miata is a inline 4 cyl, that sounds like its coming from you head and not block. the noise would be very deep down so since the noise is coming from the top I say HLAs

[BATTAOUSAI]

so it was rod knock?

[Thermactor]

That's too bad, the engine looks beautifully clean

[Bowerso]

That don't sound good, how did you manage to break it?

[AAddaamm03]

Poor assembly by the person's machinist that I bought the car from. Of course he wouldn't allow me to speak to the guy or honor any type of deal. Oh well, has a big motor now. :)

[JgHaverty]

by, "big motor" do you mean a v8 swap, or the 2.0 motor?

[AAddaamm03]

V8 swap.

[tristantao]

does it knock every time you give it gas?

because i have similar sound, but its not at all noticeable when sitting still and revving. but more noticeable when driving... can it be knock?

[statultra]

LS9

[datka1980]

@JgHaverty : Hay I have the sound on my 2002 toyota celica GT. It has no sound on idle but only when you accelerate. I hope it is only rod bearing as well. how much did it cost you to fix it?

[JgHaverty]

@datka1980 Its starting out only at high rpms. It will deteriorate and get worse, im sorry. If you have some mechanical aptitude, you can purchase a used crank and get some new rods off ebay for fairly cheap and do it yourself on a saturday afternoon. Feel free to message me, and we can chit chat.

[datka1980]

@JgHaverty : I took oil pan off yesterday and it was rod bearing ticking, but only one.the crank itself was good just needed to sand with 0 sand paper.