Injector impedance

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TopCat
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My E21(s): 1980 Alpina B6 2.8
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Injector impedance

Post by TopCat »

Dear All
I thought I would share our findings/possible diagnosis on Herman's propensity to blow ECUs
x3 in 3 years!

We now have the best 061 rebuilt but the problem might be stemming from the Bosche injectors that have a peculiar part no (maybe Swiss) and have a v low impedance at 2 as opposed to the more normal 17
so we are going to change the injectors as well as ECU and keep my 074 as spare
will keep you posted
Last edited by TopCat on Thu Apr 30, 2015 10:20 pm, edited 1 time in total.


Regards
Topcat
Isle of Man Inverness
1980 BMW E21 Alpina B6 2.8
1991 BMW E30 Hartge H26
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Jeroen
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My E21(s): '81 323i Baur
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Re: Injector impedance

Post by Jeroen »

A much lower impedance will defo put more strain on the transistors switching the injectors, this switching circuitry is a known weakpoint for many ECU's btw. Issues with wiring, impedance/resistance, oxidation inside the ECU, all common causes for ECU failures. On the 320iS I had the resistors on the ECU replaced by an updated version of the transistors as a preventive measure but these components will be different to yours I guess. Blown ECU's don't have to be ready for the scrap heap, it can be good to have them checked, perhaps they can be repaired.

But back to the likely cause, these injectors. Are these of the correct type as per Alpina spec? Do you have a part no? We could check with other Alpina owners perhaps, Arnold just moved his injectors around I believe. Perhaps the Alpina ECU is modified to deal with a different injector?

Oh and the Manx, wanna talk about it? :?
Regards/groeten, Jeroen
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TopCat
E21 Pro
Posts: 1079
Joined: Thu Apr 21, 2011 2:21 pm
My E21(s): 1980 Alpina B6 2.8
Facebook page: https://www.facebook.com/timothy.c.boles
Location: Isle of Man and Inverness
Contact:

Re: Injector impedance

Post by TopCat »

Ah yes - the Manx Classic- please post up my You Tubes fm Facebook?
Frantic here at work................!
Regards
Topcat
Isle of Man Inverness
1980 BMW E21 Alpina B6 2.8
1991 BMW E30 Hartge H26
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