Just picked up another 400. This one a 93 w/ 135,000 miles. All services don at 120,000 miles.
I'm experiencing the hesitation around 1100-1500 rpm like my other. I had my machanic look it over, and he said he gets a DTC 31 . We tried a used Volume Air Flow Meter, but no haps. He told me if a new Volume Air Flow Meter doesn't solve the problem the problem is the ECM. He gave me a printout w/ the circuit desrciption, diagnostic chart, and inspection procedures.

My question is if I spend the cash to get a new Volume Air Flow Meter and it doesn't cure the problem, how much is a new ECM? Or better yet, can I upgrade to an aftermarket stand alone system?

Thanks

Mousiee