im writing in on behalf of my parents who own a 1997 1.6 mx5.

problems include....

 

1. revs can drop without warning leaving car close to stalling

2. revs can rise without warning, they can shoot up to 2000rpm at idle

3. very lumpy when trying to accelerate, car jumps around and does not pull smoothly

4. when the car does stall it sometimes takes a while to get it started again, when it does fire up there is a strong smell of petrol.

 

the car has spent a few days with Mazda and they could find no problem, the workshop foreman took the car home 2 nights and each time reported no problem.

 

has anyone any ideas what might be up?

iv posted this on mx5oc but know how shit hot u guys are!!

 

regards, nick

Not a clue really mate, but did Mazda Start with the basics and actaully change anything at all?

 

Check the voltage off the battery and out of the Alternator are smooth when running with no spikes in voltage? Does this car have engine management???

 

For the sake of a few quid i'd be inclined to change the plugs as well as the fuel and air filters. I'd also check that the air intake has no vaccum pipe leak if it has one at all? I'd then be inclined to take it to a decent Krypton Tuners and get them to take a look. Most will throw up possible faults for you for the sake of £20/£30 and possibly set the idle correctly etc.

 

Could even be dirty/cheap fuel....Give it some premium brand for a bit and don't run it down to empty!..As before change fuel filter and if OK to use (Never use on a Z!) put some injector cleaner through it?

 

My best attempt at a motor i know nothing about!

im writing in on behalf of my parents who own a 1997 1.6 mx5.

problems include....

 

1. revs can drop without warning leaving car close to stalling

2. revs can rise without warning, they can shoot up to 2000rpm at idle

3. very lumpy when trying to accelerate, car jumps around and does not pull smoothly

4. when the car does stall it sometimes takes a while to get it started again, when it does fire up there is a strong smell of petrol.

 

the car has spent a few days with Mazda and they could find no problem, the workshop foreman took the car home 2 nights and each time reported no problem.

 

has anyone any ideas what might be up?

iv posted this on mx5oc but know how shit hot u guys are!!

 

regards, nick

 

Sounds like an air leak prob to me.

 

If it's the same basic engine as the older one's, there's a sneeky wee fault that sometimes occurs, that you just won't find unless you know it's there, lol.

 

Try this one:

 

Looking at the engine from the front of the car, to the left of the engine, at the back, between the engine and firewall....

 

About half way down the inlet manifold there is a large vacuum pipe which should have a rubber cap on it. It's about 1cm in diameter and an inch long.

 

If the cap isn't there, then that's your problem.

 

Someone pointed this out to me years ago when we had a 5 with this problem, and I was stunned by his knowledge. Hopefully yours will be the same and I can in turn claim "brain of the year" :hyper:

 

If it's not that, f**k knows :rofl:

 

But I'd look for other vacuum leaks ;)

i will check that in the morning!

cheers you guys...posted this on mazda forum exactly the same time and no replies as yet!

the ignition leads are prone to failing on these so get some magnicor uprated ones :)

Here's a photo in case you get lost...

 

 

I wouldn't have thought bad leads would have caused the engine speed to rise.

And no Kirbz, that's not why I fitted those Magnicor leads to mine :rofl:

glad you have posted that up, a huge help!

Sounds like an air leak prob to me.

 

If it's the same basic engine as the older one's, there's a sneeky wee fault that sometimes occurs, that you just won't find unless you know it's there, lol.

 

Try this one:

 

Looking at the engine from the front of the car, to the left of the engine, at the back, between the engine and firewall....

 

About half way down the inlet manifold there is a large vacuum pipe which should have a rubber cap on it. It's about 1cm in diameter and an inch long.

 

If the cap isn't there, then that's your problem.

 

Someone pointed this out to me years ago when we had a 5 with this problem, and I was stunned by his knowledge. Hopefully yours will be the same and I can in turn claim "brain of the year" :hyper:

 

If it's not that, f**k knows :rofl:

 

But I'd look for other vacuum leaks ;)

 

AT LAST !! :bow:

 

Somebody else that measures the same as me !! :nana2:

 

1cm diameter, and an 1" long !! :D Metricimperial !!

 

You have made my night bud ! ;)

I am constantly getting ribbed at work for this.

 

Cheers,

 

Alan........

AT LAST !! :bow:

 

Somebody else that measures the same as me !! :nana2:

 

1cm diameter, and an 1" long !! :D Metricimperial !!

 

You have made my night bud ! ;)

I am constantly getting ribbed at work for this.

 

Cheers,

 

Alan........

 

PMSL, never even occurred to me :rofl: