Resolved 90 CAS in a 91+ car

[serviceguy]

I am considering installing a '90 CAS on my '91 GST, mainly for aesthetics (no more sticking up ugly connector) but also because how brittle the CAS connector usually becomes after several hot-cold cycles of the engine.

Signals are the same, no problem there, and once replaced the different connector on the harness I was be expecting to be in business, or so I thought at first.

Then I started having doubt because I removed the cover of my '91 CAS to install it on a freshly acquired '90 CAS and realized that while the 'wheel' cutouts are the same and are located in the same position, the actual sensor is positioned differently. Has anybody done this 'backward' modification and is it possible without changing anything especially in the ECU code (which I would expect if TDC and cam position were to be detected with a different offset angle? Or am I just missing something?

I remember reading about either a Wiseman or a Moderator doing this modification and mentioning 'minor modifications', so before hacking at a otherwise good harness I'd rather confirm it can be done with somebody with direct experience.

Thanks for any input.

 

[u2slow]

I have a `90 Laser. A few years back, it wouldn`t start. The ECU threw the code for a bad CAS.

I had a spare `90 CAS, but it would do the same thing. I also had several `91 CASs. So I made an adapter cord for them. They all threw the same code!!! I came to the conclusion the ECU was bad.

I had a `91 ECU and swapped it in. In the process, I had to change a wire on the MAF, a wire for the tach, and swap in a `91 power transistor. I can`t recall making any changes to the CAS or wiring.

So, I`m running a `91 ECU with a `90 CAS with no ill effects that I can tell.

 

[19Eclipse90]

The only modification is for the wiring in the harness or the wiring for the CAS, however you want to approach it.

I know Craig (Calan) is using a '90 CAS in his '92, maybe that is who you were thinking of: http://www.dsmtuners.com/forums/blogs/calan/744-92-tsi-complete-rebuild-firewall-forward-part-17.html

Anyway, as stated above, aside from the wiring modification so that the CAS and wiring harness can connnect, it is a non-issue using a '90 CAS in a '91+ car. Think about how any '90 2.0L DSM can use a '91+ 2.0L DSM ECU without changing anything but ECU pins 6 and 14 (in a turbo car), neither of which are directly related to the CAS.

 

[serviceguy]

The only modification is for the wiring in the harness or the wiring for the CAS, however you want to approach it.

I know Craig (Calan) is using a '90 CAS in his '92, maybe that is who you were thinking of: http://www.dsmtuners.com/forums/blo...omplete-rebuild-firewall-forward-part-17.html

Anyway, as stated above, aside from the wiring modification so that the CAS and wiring harness can connnect, it is a non-issue using a '90 CAS in a '91+ car. Think about how any '90 2.0L DSM can use a '91+ 2.0L DSM ECU without changing anything but ECU pins 6 and 14 (in a turbo car), neither of which are directly related to the CAS.

Thanks Brian, that was exactly the thread I was referring to that pretty much should clarify my doubt. I guess I didn't look as carefully as I should have when I opened the two units.