Late 2.5 Main (Engine) ECU

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Dieselman
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Re: Late 2.5 Main (Engine) ECU

Post by Dieselman » Tue Aug 17, 2010 7:31 pm

Hi John,

I'm still pretty sure that with a simple wiring mod the car could be made to run properly on an old type ECU, just ignoring the MAF sensor.
iirc.The fuel pump is a generic Bosch VP38 and the ECU is also a generic one, so even one for another car altogether might well work.

I suspect if it runs but runs flat out then either the accelerator pot or cabling is shorted or the ECU is. He could try disconnecting the pot or harness to test.
91 3.0 sei M. 4852 EXY Black
92 2.1 sed M. 5740 ECZ Sable Phenicien
92 3.0 V6-24. 5713 EXY Black
92 2.1 sd M. 5685 ENT Blue Sideral
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xmexclusive
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Re: Late 2.5 Main (Engine) ECU

Post by xmexclusive » Tue Aug 17, 2010 8:52 pm

Hi Will

PM sent.
I get his engine racing symptoms on one of my late 2.5's when I fit an early ECU.

John

Dieselman
Global Moderator
Posts: 14446
Joined: Thu Jun 18, 2009 6:44 pm

Re: Late 2.5 Main (Engine) ECU

Post by Dieselman » Wed Aug 18, 2010 5:52 pm

xmexclusive wrote:Hi Will

PM sent.
I get his engine racing symptoms on one of my late 2.5's when I fit an early ECU.

John
Thanks.. ;)

I suspect the accelerator connections are on different pins, possibly deliberately to dissuade anyone from installing an early ECU to a car with MAF, which is used for EGR valve monitoring, among other uses.
91 3.0 sei M. 4852 EXY Black
92 2.1 sed M. 5740 ECZ Sable Phenicien
92 3.0 V6-24. 5713 EXY Black
92 2.1 sd M. 5685 ENT Blue Sideral
Prev
90 2.1sd M. 5049 EJV Mandarin
92 2.1sd A. 5698 EJV Mandarin
94 2.1sd A. 6218 ERT Triton
91 2.0si M. 5187 EWT White

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