Help with a Miata...

fastx19

fastx19

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Anyone here have any experience with a Miata? My parents picked up a miata and about 2 weeks into owning it, one of the spark plugs decides to break into pieces and ruin the inside of the engine. We found a used motor and put it back into the car.

It started up and ran like a champ. We took it out for a drive and everything seemed good.

Get back to home, and notice the water pump is leaking... Swap out the pump and now we have a new problem. The car starts up when cold and sounds fine for about a minute or so, then it just dies.

Once it is even partially warm, it will not restart.

I have replace the fuel filter, pressure regulator, CAS (Cam Angle Sensor) and still no change.

I have not replaced the temp sender because it registers the temperature of the gas on the guage just fine.

Anyone have any ideas? The Miata forum seems to be kind of picky in terms of who they will offer advice too.

Thanks!

Eric
 
Sensors

If I recall, on my '93 Miata there were 2 sensors - one for the gauge on the thermostat housing and one for the ecu on the coolant outlet at the rear of the head. Bet you the one on the back is unplugged or bad. The temp gauge would still read OK, but the ecu would always be in 'cold start' mode. Good luck!
 
go too

Grassroots Motorsports discussion forum there is more Miata freaks and geeks there than you can shake a stick at.

You will have to create a loge in but it will be worth it if you get your answer.
 
fastx19 said:
The Miata forum seems to be kind of picky in terms of who they will offer advice too.

Thanks!

Eric
Click to expand...

Eric, you didn't make the mistake of telling them you owned an Italian car, did you? Nothing seems to make them pickier...
Unless you also beat them at an autocross in a Fiat. That'll get you black listed!
My employee needed a motor for his Miata (the early 1600s break off the nose of the crankshaft!), and the only guy he could get to talk with him locally was the guy that trades TTD with me at the local autocrosses, in his EVO!
I guess he also has trouble on the forums, something about 4 wheel drive...
 
Dont you just hate those forums. I had a turbo eclipse that I was putting back together to flip.The guys on the forum were pretty moody. Getting help was like pulling teeth. Theres also a fiat forum that leans that way at times.
 
Yea, 1600cc Miata's do that. Mazda did not design the key slot on the crank properly, adding insult to problem, there was a problem with the bolt on the end of the crank that keeps the crank pulley on..

The failure mode is snapping off the front end of the crank, fix is replace the engine or replace the crank and all the associated bits that got injured when the front end of the crank broke off..

Mazda fixed this design problem later....

Goes to prove, Japanese does not always means good design and reliable under all conditions..

Chris Obert said:
My employee needed a motor for his Miata (the early 1600s break off the nose of the crankshaft!)..
Click to expand...
 
Miata uses a "wasted spark" ignition system. 1600cc engines had "electronic dizzy" or basically two optical sensors 180 degrees apart inside a dizzy housing to trigger the two ignition coils. later Miata's (i think up to 97') used a cam position sensor, again a wastes spark system, but it is tied to the engine ECU..

Email me of list and I'll copy you the relevant Miata factory service diagnostic instructions.. The Mazda has on board diagnostics..

Replace the timing belt if the water pump is change as the water pump is behind the timing belt & tensioner bearing, the front crank seal and drive belts too while you're at it.

Make absolute sure the cam timing is correct before trying to turn the engine over with the starter, this is an INTERFERENCE engine.. just like some earlier FIATs... That Miata will crunch valves and etc if the timing belt is put on wrong..

There are times when I ended up wrenching on the Miata, not as interesting as the X...

Bernice



fastx19 said:
Anyone here have any experience with a Miata? My parents picked up a miata and about 2 weeks into owning it, one of the spark plugs decides to break into pieces and ruin the inside of the engine. We found a used motor and put it back into the car.

It started up and ran like a champ. We took it out for a drive and everything seemed good.

Get back to home, and notice the water pump is leaking... Swap out the pump and now we have a new problem. The car starts up when cold and sounds fine for about a minute or so, then it just dies.

Once it is even partially warm, it will not restart.

I have replace the fuel filter, pressure regulator, CAS (Cam Angle Sensor) and still no change.

I have not replaced the temp sender because it registers the temperature of the gas on the guage just fine.

Anyone have any ideas? The Miata forum seems to be kind of picky in terms of who they will offer advice too.

Thanks!

Eric
Click to expand...
 
You guys are awsome!

Thanks a bunch everyone. I am going to replace the water temp sensor on Tuesday (have to order it) and see what the results are.

No, I did no get ride of my Fiats. It happens to be my parents car and I am simply lending a helpful hand.

Thanks again guys and gals!

Eric
 
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