Mechanics

MAZDA MX3 DISTRIBUTOR PROBLEM

1993 Mazda MX3 • 220,000 miles

Car wants to die at a stop. When accessories are turned at idle like heater, lights, or touching brake pedal rpm's drop so low it dies. Recently tuned up, new vacuum hoses, new maf, no codes, tested iac valve and tps both react how their supposed to when unplugged and resistance is in correct range, injectors are clicking fine, cleaned throttle body and air boot, alternator is putting out 14.5 volts, new fuel pump and filter. Pressure is good, vacuum guage reads about 20 steady. Any ideas?
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Gatertamer
January 5, 2013.



Thanks for your help. The wires all have good continuity. One last question. The diagram says at idle the G signal (2g on ecu) at idle should be 1.5V. It measures at 5V both at distributor connector and ecu. What is that telling you. Again thank you

Tiny
Gatertamer
Jan 27, 2013.
That should mean the distributor crank sensor is not providing the correct pulsing.

KHLow2008
Jan 28, 2013.
I put brand new dist. In took care of cel. However still wants to die when accessories turned on. Rpm's drop a little when you turn on lights.A little more when you turn on heater and usually dies when you hit brake pedal. Tested all voltages to ecu, cleaned IAC and throttle body, new vacuum hoses, air intake boot no cracks, new fuel pump and filter. Resistance checks on all sensors and controls are within spec. Alt is good. Could it be compression? Any ideas

Tiny
Gatertamer
Feb 6, 2013.
What is the idling speed?
Did you check the ignition timing?

KHLow2008
Feb 7, 2013.
Idling speed is about 900. Timing mark is about 2 inches behind where its supposed to be. Im not a tooth off either.I have lined everything up several times to guarantee TDC and the timing mark still isnt even close.I have tried jumping the ten and ground and adjusting the air screw to 750 for the idle but its too low and dies every time. Idling speed is a little high so it doesnt die as often. Thanx again

Tiny
Gatertamer
Feb 7, 2013.
What I meant is the ignition timing. It means the distributor position and you need a timing light to check that

KHLow2008
Feb 8, 2013.
I did use a timing light thats how I know it is way off. Its not even close to the mark

Tiny
Gatertamer
Feb 9, 2013.
Either the distributor is wrong or the timing belt is off its mark if the ignition timing is too advanced or retarded.

KHLow2008
Feb 10, 2013.
I really appreciate all your expert opinion on everything. You have helped me narrow it down alot.I have used origional dist. Used dist. And new dist and timing is in same place with all of them.I lined up marks on camshaft sprocket with marks on head. Crankshaft sprocket with mark. Rotor is pointing to no.1 tower. And stick hanger through no1 spark plug hole and can feel top of piston up high so I know its at TDC. Am I missing anythiing. Could engine be so worn that I should try manually on purpose moving it a tooth or two in either direction? Checked compression and no.3 cylinder is pretty low. About 60. Again thanks for your help.

Tiny
Gatertamer
Feb 11, 2013.
If distributor ia gear type, move it one notch and recheck the ignition timing.

At 60 psi, the cylinder is bad.

KHLow2008
Feb 12, 2013.
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