Horrible knocking noise under acceleration

fir3 · Post by **fir3** » November 17th, 2005, 1:52 pm

My 1.6 dohc 97 mx3 has a very ugly and anoying and horrible knocking noise that happens when I accelerate:

1) Does not happens when car is idle...
2) Does happens in a slow speed
3) Does happens when I "force" the engine (when I step hard in 2nd and 3rd)
4) Does happens any time, cold or hot, no matter the climate

ovendenk · Post by **ovendenk** » November 17th, 2005, 2:08 pm

is it proportional to the speed of the engine or the wheels? ie. when you change gears and the engine speed drops, does it become less noticeable? this will help to determine if it's an internal problem or not.

fir3 · Post by **fir3** » November 17th, 2005, 2:21 pm

is it proportional to the speed of the engine or the wheels?
The sound goes away as speed increases...

It only happens (for example) when I'm in 3rd and I need to slow down, I change to 2nd gear and step hard I can hear the knocking sounds...
But it goes away as soon I change to 3rd and speed is increased.

azazel95 · Post by **azazel95** » November 17th, 2005, 4:39 pm

fir3 wrote:is it proportional to the speed of the engine or the wheels?
The sound goes away as speed increases...

It only happens (for example) when I'm in 3rd and I need to slow down, I change to 2nd gear and step hard I can hear the knocking sounds...
But it goes away as soon I change to 3rd and speed is increased.

Maybe axles or your tranny getting ready to go?

BTW, if you're slowing down, why do you drop a gear and slam the gas? That would just cause an increase in speed.

fir3 · Post by **fir3** » November 17th, 2005, 7:28 pm

3rd gear - slow down - 2nd gear - and go...

azazel95 · Post by **azazel95** » November 17th, 2005, 9:56 pm

Ah I see I thought you were referring to downshift-stopping not just slowing down I see now.

mcfly · Post by **mcfly** » November 18th, 2005, 9:12 am

i have the same problem basically, when i turn left, my right front wheel makes knocking noises, im going to fix my axle today. perhaps you should check yours?

fir3 · Post by **fir3** » November 18th, 2005, 11:47 am

It can't be the HLA, can ?

Thunderstorm · Post by **Thunderstorm** » November 18th, 2005, 5:02 pm

fir3 wrote:My 1.6 dohc 97 mx3 has a very ugly and anoying and horrible knocking noise that happens when I accelerate:

1) Does not happens when car is idle...
2) Does happens in a slow speed
3) Does happens when I "force" the engine (when I step hard in 2nd and 3rd)
4) Does happens any time, cold or hot, no matter the climate

Hi fir3!
Most Curious.
Couple of questions to aid in your diagnostics.....
BTW, I have a 1.6 DOHC of similar age;

Exactly what mileage do you have on the clock at the moment?

Has your MX-3 RS been doing this right from when you purchased it?

How many owners has it had?

What country are you located in? (Don't tell if you don't want to)

Do you have enough gear oil in your gearbox? Is it the correct type?

Have you had your running gear inspected? Loose rotors?

Could a part of your exhaust system be loose? (Clutching at straws here!)

Could one of those things that cushions the vibes between the engine and the body have failed? Rare, but if the engine was ever removed in the past and some incompetent nit botched the re-installation of the engine, one of those pads could be partially destroyed, hence your engine moves about under full thrust in certain gears and might induce this horrid noise.
Or maybe not. Just a lateral thought ok?

Hope I may have helped somehow

Thunderstorm

fir3 · Post by **fir3** » November 18th, 2005, 7:48 pm

Thunderstorm wrote:
fir3 wrote:My 1.6 dohc 97 mx3 has a very ugly and anoying and horrible knocking noise that happens when I accelerate:

1) Does not happens when car is idle...
2) Does happens in a slow speed
3) Does happens when I "force" the engine (when I step hard in 2nd and 3rd)
4) Does happens any time, cold or hot, no matter the climate
Hi fir3!
Most Curious.
Couple of questions to aid in your diagnostics.....
BTW, I have a 1.6 DOHC of similar age;

Exactly what mileage do you have on the clock at the moment?
42.000 miles

Has your MX-3 RS been doing this right from when you purchased it?
yes

How many owners has it had?
4

What country are you located in? (Don't tell if you don't want to)
brazil

Do you have enough gear oil in your gearbox? Is it the correct type?
don't know if it is the correct type... would you suggest one ?

Have you had your running gear inspected? Loose rotors?
not yet...

Could a part of your exhaust system be loose? (Clutching at straws here!)
I will check that..

Could one of those things that cushions the vibes between the engine and the body have failed? Rare, but if the engine was ever removed in the past and some incompetent nit botched the re-installation of the engine, one of those pads could be partially destroyed, hence your engine moves about under full thrust in certain gears and might induce this horrid noise.
Or maybe not. Just a lateral thought ok?

I will check

Hope I may have helped somehow

Thunderstorm

freyguy_412 · Post by **freyguy_412** » November 19th, 2005, 1:13 am

How's your ignition timing?

MX-3.com

Horrible knocking noise under acceleration

Horrible knocking noise under acceleration

Re: Horrible knocking noise under acceleration

Re: Horrible knocking noise under acceleration