90 MONTERO 3.0 V-6 WON'T START...

" snipped-for-privacy@peoplepc.com" wrote in news: snipped-for-privacy@h40g2000cwb.googlegroups.com:

Have you checked your timing / belt, and the engine rotation sensor, and the TDC sensor.

N

No, I haven't. Have you had experience with this exact engine? Will a failed TDC sensor and an engine rotation sensor cause no spark? The timing belt was replaced a few years ago and appears to be fine. Any idea why the voltmeter barely moves when testing the engine computer? Thanks.

Nirodac wrote:

" snipped-for-privacy@peoplepc.com" wrote in news: snipped-for-privacy@i12g2000cwa.googlegroups.com:

No experience with this specific engine or vehicle. However, the sensors are very critical to your engine timing, if one fails, you will not get a spark. The sensors are easy to test. The service manual has all the details. Check that all sensor connections are well seated, and not corroded. Sensor output is very low current and bad connections can happen. Sorry, can't help you with the meter, but, I didn't think the meter circuit went through the ECU for this year. Might want to check the connectors the support the meter circuit also.

N

The 89 ECU was a single year model. You can use an 89 ECU -IF- you also swap in the 89 distributor.

The 90 and 91 model ECU's are the same.

I own a 1991 3000GT with the 3.0L engine. The Mitsubishi Factory Service manual says to check the following if there is low spark or no spark:

1. Ignition Coil
2. Crank Angle Sensor
3. Power Transistor
4. Spark Plugs
5. Ignition Cables

The schematic shows the following inputs to the ECU:

Intake Air temperature Sensor Atmospheric Sensor Idle Switch Top Dead Center Sensor Knock Sensor Air Flow Sensor Speed Sensor Inhibitor Switch Ignition Switch Crank Angle Sensor ELC-4A/T Control Unit Engine Coolant Temperature Sensor

which drives the power transistor which also gets inputs from the ignition switch and engine speed detector. The power transistor then generates the input signal to the ignition coils which produces the high voltage spark.

Merry Christmas. Good luck. Let us know what you find.

Bob

"Mr.G (@¿@)" wrote in news: snipped-for-privacy@48g2000cwx.googlegroups.com:

The ECU (in most cases) can be repaired for about $5.00 CDN in parts. To check the ECU, to see if it is functioning, all you need to do is attach a voltmeter to the diagnostic port. Watch for meter movement. If the voltage remains constantly high, this indicates ECU failure. If the voltage remains constantly low, it could be ECU failure or the power feed to the ECU isn't there. If the needle of your voltmeter pulses, at a constant rate, the the ECU is fine. If the needle pulse at an unequal rate, the ECU is pumping out a fault code.

N

Just 3 days ago my 90 Montero failed to start, zero spark. I checked my ECU and was given the code for "No.1 cylinder top dead center sensors" which requires the replacement of the distributor (if anyone knows where we can purchase the electroics of the distributor alone, please email) I have since replaced my distributor and check through the wiring harness after which I failed to make spark again. I had a spare ECU that I thought was good but all it did was fire-off the coil continously and then that ECU failed. I replaced the ECU with the original unit, turned the engine over and again no spark; checked ECU for code received same as before. Question being for everyone out there how does a person check the distributor for correct operation, I am not speaking of the rotor and cap but the internal electronics? Also I have also replaced the coil with its components and still no spark which steers me back to the distributor, any thoughts?

I had a 91 Montero that my friend no drives, after 245K miles the distributor had failed, after a year+ of just sitting around we replaced it and she fired right-up!

Many thanks,

90 M> Thanks in advance to those willing to help ! I would be glad to call

"90 Montero" wrote in news:1167517700.602181.76150 @h40g2000cwb.googlegroups.com:

replacement

Have you check all your harness connections, between the dist and the ECU. Unplug them, check for corrosion then reassemble.

How is your timing belt, has it jumped a few teeth.

The service manual has detailed instructions on how to test each component in the ignition system, including the transistor. If you don't have it, check the local library. The fact that the ECU is outputting a code would ,generally, rule out an ECU problem.

I don't have any specific information on the 6 clyinder, just general Mitsu knowledge.

N

Nirodac, thanks for response. The timing good, there is no spark from coil which I know works well (my buddy got wacked from it when the other ECU made it fire off repeatably) My electrical connections look good and I have also check wires for continuity. I also received a signal from the ECU stating for the "Motor Position Sensor" which is located in the distributor too could be at fault; one of the items my manual recommends checking with this fault is the "Throttle Position Sensor" I have checked this too with the values looking good and compared these values to a spare unit I have and they agree with each-other. I am brought back to my "new"distributor which has the No.

1 Cylinder TDC & the Motor Position Sensor within it. I have two manuals for the Monteros and neither one shows how to check the distributor its-self; any feed back on what can be checked within the distributor other then cap/rotor?

Thanks!

90 Montero