BMW M5 Forum and M6 Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
1,731 Posts
Discussion Starter #1
Did Alpina just put another chip in BMW's (or Bosch's) ECU or was it completely reprogrammed?
I have just reshelled a badly rusted B9 and put everything into a later e28 535i shell (approx 18months difference) but now we have the engine place, there are differences where the wiring is concerned. We have the car running using the 535i ECU, but it hunts badly, and the Alpina ECU/Car had a different warm up valve to control it's idle when started from cold and it would appear that the later 535i has a different feature.
So the question is can I plug the Alpina ECU into the socket of the 535i and hope it all works, or will it cause problems?

Any help would be appreciated, would like to get to use it now it's all in the car!
Thanks

Andrew
 

·
Registered
Joined
·
44 Posts
ANDY

i think your problem may be down to the fact that you have used the basis of a 535i to do your conversion. the b9 used the 528i as its base and so it is quite possible that there is a different wiring loom.

i have checked an article from september 1984 and it quite clearly states that the 528i engine was dropped out and the alpina unit dropped in. then the jetronic ecu was simply swopped over for the motronic alpina ecu.

my suggestion is that you talk to fritz bitz in taunton, as he has recently put a b9 engine into his 6 series and is very well up on e28 issues. i am sure he can help you. you will find him advertising in all the usual bmw magazines as i dont have his number to hand.

BEST OF LUCK!

DAVE W
 

·
Registered
Joined
·
1,731 Posts
Discussion Starter #3
Dave
Cheers for that, we knew that the base was a 528i, but when Alpina did the conversion they went the whole hog and swapped over to Motronic from Jetronic which entailed the complete loom for the engine etc.
In theory the later 535i would be able to accept the Alpina items as that is Motronic as well, however the bi-metallic warm up valve used on the Alpina originally was supersceded by BMW when they introduced the Motronic II and fitted a cold start valve system!
We have the car running, using the 535i ECU just looking to see if the Alpina ECU will just plug in.
I will give Fritz a call to see what he can do to shed some light on this problem.

Many thanks

AG
 

·
Registered
Joined
·
1,731 Posts
Discussion Starter #5
kees said:
Any news Andy?
Well, progress rather than news! The later ECU's were different to the earlier e28's ECU's, and it would appear that the pin location for a few of the items are in different positions when both ECU's are compared. So we have re-used the original 535i ECU, and have just run the car as is, seems to be OK, although it's cold start layout differs, so this will need to be sorted, but it runs, goes, but hunts on tickover. So I either need to think about having the electrics amended so we can use the original Alpina ECU, or have te 535i's ECU 'chipped' and sort the cold start problem out.
 
1 - 5 of 5 Posts
Top