jreid1000

Here is the situation: My 1994 Miata with a 1999 Camaro LS1.

The engine starts but only runs for about 2 seconds and stops.
I am sure this is the VATS doing this. My multimeter connected to the ECU fuel pump relay trigger wire shows that power to the relay stops after about 2 seconds. Jumping the fuel pump keeps the pump running but does not stop the engine from shutting off. I believe the VATS also shuts down the injectors.

So far, all of the search results I have found on line involve changes to the GM key, ignition lock/wiring or body control module, none of which is in the Miata.
Some guys suggest reflashing the GM ECU and others offer their "build your own" bypass box. Any information on this would be greatly appreciated.

Thanks!!!

Jim

charchri4

You have to have it tuned anyway so tuning out VATS will be covered. I'd just have it bench tuned now rather then mess with defeating the VATS.

For a lot of shops if you pay for a dyno tune they will do a quick bench tune for you to just get it running enough for you to work the bugs out. Besides VATS a bench tune will need to remove the rear 02s, adjust the speedo for the diff, set the fan temps, remove the CAGS (assuming you are a T56) and depending on how you do the A/C take out the computer control for that too. A good tuner can do all that in less than half an hour.

Once you get it running and the bugs worked out then put it on the dyno and they will tune it for the lighter car, custom intake, different exhaust, cats or no cats, etc. If the shop is good it will run a lot better than it did with the stock Camaro tune for sure.

If you don't want to do a dyno tune or don't want to pay the 500+ bucks for it I have had pretty good luck with Steve Frost doing bench tunes. You will see his name (tuned by Frost) a lot on LS1tech and he does good work. For 200 bucks plus shipping he can get it close for you.