MX-3.com

I had just purchased a 1994 mx-3 GS, its been giving me a few problems...

Idle jumps
Engine hesitates until i reach 2000 rpms or if i floor it.
driving at a constant speed for a while, engine light comes on and engine loses power.
takes about 10 seconds to start up

I did the diagnostic test and i got codes 04, 17 & 24. I replaced spark plugs, spark plug wires, and distributor. I brought the car to 2 different mechanics and they were both stumped, they had brought it to the dealer and they were even stumped. They changed the crankshaft sensor and that got rid of codes 17 and 24. The car runs a bit better but the same problems still occur. Any suggestions?

are there any modifications to this car like a cold air intake?

you might have to reset your idle.

The idle and hesitation could be a vaccuum/hose leak. I had the same thing in mine and it was hesitant/jerky in the low rpms until I noticed I had a crack in the accordian (I have the stock intake hose and air filter). Not sure about the CEL though...

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Yea I have a cold air intake

are the valve cover breathers hooked up into it? when i ran my ze with stock accordion tubing i had a perfect idle, since then i made a cold air intake that i have not plugged the breathers into and now it has a jumpy idle. same problem with my RS at one point as well.

check to make sure those are plugged in.

projectzemx3 wrote:are the valve cover breathers hooked up into it? when i ran my ze with stock accordion tubing i had a perfect idle, since then i made a cold air intake that i have not plugged the breathers into and now it has a jumpy idle. same problem with my RS at one point as well.

check to make sure those are plugged in.

Are you talking about the hose that connects to the accordion or the little one that goes to the box?

So I took the car to a mechanic, the car was sent to 2 different mechanics to find the problem. They ended up changing the crank shaft sensor. I go pick it up today, take it for a drive, it drives a lot better no more bogging out, but I still have an engine light (code 04) and it still struggles to start and the rpms are still jumping. Any suggestions?

Not much help on this one cuz I have the same prob. Code 4 came after I changed my disty, still have old one and will try hei mod on it as it didnt have code 4 issues. I believe thats the code for cam position sensor, which is built into the disty, which also makes the car take about 5-10sec to start. Good luck

still have no idea whats wrong with this thing... any ideas?

I have same problem. when i start my (Mazda mx3 v6 24v 1996) and engine is hot, rpms Start jumping up and down!!! no idea where is a problem. In Mazda service they check on computer and told me its fine!!!

Its your disty!!
When you get code 4 it looses the ability to track which cylinder is at which position so what it does is fire all 6 injectors every time since it doesn't know the specific cylinder postion.

The only way your car is running is because in the 92-94 MX-3 they have essentially 2 crank sensors, one on the crank and one in the disty. Where later years drop this sensor and only used the crank sensor.

The sensor that it is telling you is bad is in the Disty. You cannot just replace the sensor, you will need to replace the enitre disty or find the electronic board from another disty and install it in yours.

Hope this helps