If he is a qualified auto lecky and he appeared to do the work I would just swap the ECU. He would be well versed in making such a call not hard if you know what you are doing. If it doesn't help you will know 2 things, the ECU is OK and that guy isn't worth a pinch of the proverbial, although I would take his advise before the internet any day. Hell this forum cant or wont even answer your OP question. 23710-40P11 is for a VG30DE (NA) Auto 11/89-03/90 Alternatives (JDM) 23710-40P12 23710-40P13 (End date of FAST listed comparability 08/92) 2371M-40P13 (M is for re-manufactured and no issue.) I would also use these (ADM) 23710-39P11 from 11/89 23710-39P12 to 08/92 An ECU should cost between $50 and $150 and should be pretty easy to find.