Griswald

Is it possible to use a regular GM scanner on a MEFI 1? What parts/adapters would I need? My main objective is to check timing.

Thanks!

Young Performance

I don't believe that you can use a GM scan tool on a MEFI. I've never heard of it, and since GM never used it in a car, I would say no.
To set the timing all you have to do is put a piece of wire or a paperclip across the A and B terminals in the diagnostic plug. This will put it in base timing mode and you can then set the timing to 8 degrees.

Griswald

I'm more concerned with total timing vs base. Thanks.

Dave_N

There are a few automotive scan tools that will connect to a MEFI system if you have the right software cartridge and cable.

If your just going to use this to monitor your own MEFI 1 engine, you can buy "MEFI Scan" software for about $200 that would allow you to monitor timing advance and knock retard (along with other engine parameters). With the least expensive handheld marine scan tool costing about twice that much, it may be a good way to go (assuming you have a laptop computer).

Dave

Griswald

That sounds like it will do what I need. I have a procharged 502 and I want to see what timing is at advance when the boost comes in. Thanks!