Car chokes and stalls

[carminemignelli]

Ok so i have a 92 mazda mx-3. The car is in great physical condition but i can say the same about the motor. I have the 1.9l V6 and it has 276000km on it. The starter fuel pump spark plugs and distributor caps were all changed but i have this really annoying problem. I start the car , i start to drive its all fine however once the engine warms and the idle goes down to about .8 rpm (starts at 1.5 rpm) it will start to choke. I'll be driving going about 50km/h and the gas just stops going to the motor. It makes a how can i put it ... farting noise. and sometimes the gas will slow down to the point where the car will stop in the middle of the street. When im at a red light il put in in first gear and the rpm will start going all over the place ranging from almost 0 to 2 and i dont know why... ive used injector cleaners about 3 times already (putting supreme gas when doing so) and the problem still persists. Ive contemplated of getting the 2.5 V6 from japan but im not sure if i should just try to fix this ... the problem is i dont know how... Can anyone help or shoot some ideas????

If any ideas come id really appreciate it... you guys can even email me at

carmine.mignelli@hotmail.com" onclick="window.open(this.href);return false;

[Ryan]

Just so you know, proper idle speed is around 650 RPM.

Check all of the intake tubing for cracks and leaks. That is the #1 most common problem to the issue you're describing.

Also, consider doing a proper tune up, setting timing, idle speed, throttle position sensor. Its likey in the FAQ section, accessed from the forum home page...

[Whisper]

800 RPM idle is not too bad.

Might be a vacuum leak somewhere... Also how's your O2 sensor?

Is it throwing any codes?

[carminemignelli]

honestly i know nothing about engines im really good with body wor and sound system wiring :s so ya i really dont know where the O2 sensors are lol

[Whisper]

You own an old car, so time to start reading up on where things are and what they do. It's actually quite simple, once you understand basic principles and systems.

Oxygen (O2) sensor is screwed into the exhaust pipe, not too far from the engine, before the catalytic converter. It sniffs exhaust gasses and detects your air/fuel mixture, it then sends the signal to the computer (ECU), and ECU adjusts the fuel amount based on that signal. Typically if your O2 sensor is bad it will send wrong voltage and ECU's self diagnostic system will store an error code. There are threads here that tell how to read the error codes (if you search) using a paper clip as a jumper. It's super easy. You should look into that and see what error codes come up, if any. If nothing comes up, it's likely a mechanica issue, like a vacuum leak.

Also, RPM is read in x1000, it even says so on the tachometer. So .8 is actually 800 RPM, and 1.5 is 1500 RPM.

Oh and the engine you have is a 1.8L not 1.9L.

[carminemignelli]

lol ya i know its in the 1000s i just put the estimation form the dash lol but thx alot

[Sleeper6]

Somehow I sense a faulty distributer but the "farting" noise your talking about is a bit tricky. Where exactly is this coming from? Is it more of a backfire or from underhood? If so check the accordian intake tube and the vacuum lines from your booster to see if the noise is from there, just play with the butterfly on the throttle to replicate if your going down the road and let off after a bit to see if it happens.

Also did you change your filter when you did the pump? Maybe some sediment got into the lines and is clogging it keeping you from getting fuel not to mention theyre easy to change and only cost a few bucks.

Either way I say possible faulty disty, but change the fuel filter if you havent by now, its down by the tranny and super easy. Also while its acting up check your pressure at the injectors and see if your holding okay.

[Whisper]

Yeah, I was thinking fuel issue too, but he says it only happens when the car is warmed up.

[carminemignelli]

well i donno if im gunna change the distributor or the fuel filter just yet cuz i just changed them about 2 months ago

im just getting really fed up im gunna try what u guys sugessted if that dosent work im just going to drop the KLZE

[carminemignelli]

this is what i got from carpros.com


Check the fuel pressure and test the throttle position sensor and also clean the out the MAF sensor with a electronic cleaner and see what happens
now i donno if this is any good but what im planning to do is to make a list of all sugestions and just go through them hopefully that will work

[Sleeper6]

this is what i got from carpros.com


Check the fuel pressure and test the throttle position sensor and also clean the out the MAF sensor with a electronic cleaner and see what happens
now i donno if this is any good but what im planning to do is to make a list of all sugestions and just go through them hopefully that will work

To start with did you get a new disty or a used one? Also I doubt its the VAF as Ive never seen one go bad on a KL. Otherwise Im still curious where the noise is coming from, under hood or out the tailpipe b/c that will help narrow it down. As for the tps if it was the cause you would be seeing a constant erratic throttle not just when its warmed up, witch is what points me to the disty as thats the main symptom of a bad ignition module is that as it heats up it will expand and if theres any hairline fractures you loose contact and loose ignition

[Whisper]

Also hairline cracks in vacuum system expand with heat.

[carminemignelli]

i usually hear the farting noise down by the exhaust and now for some odd reason i hear a ticking sound from there also... but now since winter is coming along my car is in storage so im going to start working on it

[Ryan]

I would suspect ignition system as well.


Running like crap when hot (but not cold) is a proven sign of distributor/ignitor failure.

Its also an issue with vac leaks, as heat causes stuff to expand/shift, changing the level of leak...

[PATDIESEL]

Sounds like you said your issues come when the car warms up right.. If I read thta right then you need to look at systems that change when at operating temperature. The typical sensors that tell the ECU the cars temp are the water temp sensors and the O2s. I would change those and I bet most if not all your running issues disappear. The "farting" I would guess is a exhaust leak since you say it is not in the engine bay, but further down the car. Since you said something about winter and storage I bet you have a rust hole in the piping.
Since this is my first reply to you, welcome to the forum and good luck with the car.