Ignition module reliability

[jackherer 543]

IIRC the BX loom has the ground wire to the ignition amp plate and the 405 doesn't. I think they run OK with it disconnected too.

[karabas 21]

18 hours ago, SRDT said:

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.

I used to have blue one on the car. Replaced with a new black Taiwan made Bosch. It didn't start. Taiwan black Bosch modules are not reliable I think. (XU9JA)

Edited September 26, 2019 by karabas
add engine code

[estland 3]

Another question.

 

When choosing a new distributor rotor arm I came across with different types of them. Some have 5k ohm resistance, others 1k. Also found some with no resistance. As my new Bosch HT leads had noticeably higher resistance than the old ones, should I avoid the 5k ohm rotor arms?

Edited October 6, 2019 by estland

[estland 3]

I started the car with old original blue ignition module and no misfire anymore. Ran cleanly to redline. As it being broken engine soon stalled

 

Strange things... same time new Bosch module gave a strong misfire.

 

Can anyone recommend any other part brand? Huco(hitachi) module did not also work.

 

 

Edited October 12, 2019 by estland

[DamirGTI 342]

Old blue Bosch modules last literally forever .. i never had one failing and have a few of them now being old some +20 years , and they still work .

 

I think now it's pretty much clear that something makes them burn out .. Some kind of short within the wiring loom or the ECU triggering the module over excessively .

 

D

Edited October 13, 2019 by DamirGTI

[SRDT 182]

You will never change your module until it's fryed so it could be unrelated.

Or maybe the problem slowly destroy the aging blue module and causes misfires with the new black one.

[estland 3]

On 10/13/2019 at 10:09 PM, SRDT said:

You will never change your module until it's fryed so it could be unrelated.

Or maybe the problem slowly destroy the aging blue module and causes misfires with the new black one.

When testing old HT leads I saw that the coil HT lead had insulation damage and when touching the engine, the engine died instantly. Maybe that was the reason at the beginning.

 

I bought a new second hand original module now and car drives normally. Overall module gets warm, but not hot.