The Tech 1 is good. I've seen a few on e-bay, too.
I have an older OTC Monitor 4000, and a Snap-On MT2500, and at the shop I have a Snap-On Modis.
Any of the Snap-On scammers are good if it has the correct(ie: newer)
software. Since the '94 is not OBDII, you might not neeed a scammer
with that capability, but it sure helps to have it if you do need it.
Also, bi-directional commands are great...any of the Snap-On scammers
will have that, depending on the software version installed. They are
also printer-ready, and will query the other control modules mentioned
by toptechx6.
Buying a used scammer could be a crap shoot....you never know if it will work until you actually try it, so I wouldn't pay a lot for something I couldn't check out first. You can also sometimes find used scammers at pawn shops, and swap meets, that would be easier to check.
If all you want to do is pull codes, then any lower priced "code reader" would be fine. You can get these at just about any parts house, but most of the ones available now are OBDII specific, and may not give you anything on the '94, so be sure to ask when looking to buy, if it will work on the non-OBDII system.
hth
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