My son's 92 Tracker jumped the timing belt and after I got it running I managed to clear all the codes, cleaned the EGR, idle valve, fixed several vaccum leaks ( it was idling at 3k) changed the inlet air temp sensor (got one from Suzuki Marine in Japan) and finally got it idling nicely. Then I spent a couple of days fixing the tranny after which it sat for a couple of days. When back to it today to work on the RWAL brakes and its idling at 1500! So I let it warm up and it idled back down to ~850 though I can hear a bit of a sine wave that isn't discernable on the guage and the CEL is back - no codes! Tried multiple times to get a code with no luck. It goes away once it cools back down, has plenty on coolant, a new WTS and guage sensor. I'm stumped.