Ignition module reliability

[estland 3]

How long these units work before they usually fail?

 

My new Bosch ignition module lasted only for 3 years. Now I bought a Huco one, maybe it's better?

[petert 588]

Seems odd. Did you use heat transfer paste?

 

Standard ecu? Perhaps you have excessive dwell time?

Edited June 22, 2019 by petert

[estland 3]

Paste was added yes, now a bit dry, but still there.

 

All standard engine. What do you mean by dwell time? Car being too rarely used?

[SRDT 182]

Dwell is the ignition coil charge time but if you don't even have a chipped ecu it must be something else.

[estland 3]

Hello again,

 

new ignition module lasted only for 200 km.  Does anyone have any ideas where to look for fault?

 

Interestingly the module was very hot when it died. Thermal paste was added before ofcourse.

Edited July 20, 2019 by estland

[wicked 103 3 Cars]

Proper grounding and check the driving pulse from the ecu. Sloppy switching slopes will cause extra power dissipation in the ignition module. 

[petert 588]

Did you have the correct ignition module? I would find someone with a digital oscilloscope and check the coil charge time. It should be approx. 3ms.

[wicked 103 3 Cars]

It can also be that your coil has an internal short and draw too much current. 

[estland 3]

22 hours ago, wicked said:

It can also be that your coil has an internal short and draw too much current. 

The resistance of the coil was within the limits. Could the short come when the engine reaches the work temperature and the coil also warms up?

[estland 3]

One more interesting note. For a while now I've had a jerky rev counter. To this day I related it to worn mechanism, but could it indicate a coil failure?

[Tom Fenton 1,542]

In my experience its actually the pick up inside the distributor that is the issue, that provides RPM feedback to the dash plus the ECU for the fuelling. When the rev counter flicks the engine also momentarily dies. Try another set of clocks if you can to see if it makes any difference, if it is still the same try another distributor.

[Anthony 1,003]

Is this a Jetronic or Motronic equipped car?

[estland 3]

10 hours ago, Anthony said:

Is this a Jetronic or Motronic equipped car?

Motronic M1.3 

[petert 588]

And did you verify the dwell time?

[wicked 103 3 Cars]

The motronic has a bdp sensor for the ecu. The rev counter however is still attached to the coil. A failure of the coil can be temperature dependant and can cause a drop in inductance, meaning more current on the primary side (ignition module) and less on the secondary side: weaker spark, possibly hesitating rev counter. 

 

If you don't have the means to measure the dwell, I would replace the coil first. It can also be something else but this is an easy and cheap fix.

[estland 3]

Sadly nothing new, as I'm still waiting for the warranty claim answer.

 

Parts shop page offers a coil pack instead of a distributor. Can it be used on xu9jaz engine?

[SRDT 182]

The coil pack is used on the ZX 1.9i, the engine is a D6E XU9JAK with the 35 pin motronic MP3.1 and no cat.
Yours is a 55 pin motronic ML1.3 so you need much more than the coil pack.

[Thijs_Rallye 87 4 Cars]

Measure the resistance of your ECU and Coil amp grounds. (Or measure the delta V over the grounds while running the engine)

 

Secondly, a jumpy rev counter usually indicates a dying or broken spark plug cable. 

[estland 3]

Sadly things have gone from worse to worse by car standing for months.

 

Now the engine can't rev more than 4000 rpm.  Engine starts to misfire and rev counter jumps between 3500 and 4000.

 

So far I've replaced: HT leads, sparkplugs, coil, Ignition module (Bosch).

 

Ecu and Ignition module earths were ok, I even just in case cleaned the earth contacts.

 

I feel that there's not anything I can do anymore. Distributor cap being faulty maybe? (Although visually it's ok)

Edited September 24, 2019 by estland

[Thijs_Rallye 87 4 Cars]

Are you absolutely positive the leads are ok? Jumping rev counter suggest it is arcing somewhere, but not in the cilinder. I've noticed that some manufacturers do not place the caps in the correct position which leads to the "clicky thingy" disengaging from the top of the spark plug.

 

Checking the dizzy cap and rotor is always a good idea.

[DamirGTI 342]

Tried CAS sensor (down on the gearbox bell-housing) ? unplug the connector and take a look if there's any oil or moisture/oxidation on the connector termilans .

If you have spare CAS sensor try to replace it .

 

Not quite the symptom for the bad CAS from my experience , but who knows ..

 

On 7/20/2019 at 10:03 PM, estland said:

Interestingly the module was very hot when it died. Thermal paste was added before ofcourse.

This sounds the most suspicious to me .. could be short within the wiring , wrong ign. module or coil type , or faulty ECU .

 

 

D

[estland 3]

New HT leads are Bosch ones, probably ok. I replaced the CAS with a spare one, no luck   Misfire remains.

 

I cleaned the distributor cap and rotor, now the engine starts with first crank.

 

Original ignition module had "MTR01" written on it, but the new Bosch one only has "Made in Taiwan" written on it. Can there be difference between them?

 

 

[SRDT 182]

Some XU9J4 owners have experienced similar problems with the new black module that bosch is selling now and had to find a NOS or second hand blue one.

Not sure why some cars seems to be fine and others have this problem. This particular module was meant to be driven by a distributor not a ECU so maybe the new one isn't as forgiving.

[Thijs_Rallye 87 4 Cars]

11 hours ago, estland said:

I cleaned the distributor cap and rotor, now the engine starts with first crank.



 

Can you post a picture of the inside of the cap, the brush and rotor?

[estland 3]

I will post it later, as I'm not near the car.

 

Does the module casing itself has to earthed? I read in one similar thread that someone had a earth wire connected to the heatsink bolt/ screw.