*This is my First try at this stuff* I'm a real old-timer so I'll apologize up front for what may be a barrage of simple minded questions. I have been reading the forum for about a month and am eternally grateful for the wealth of information for rank beginners like me.

I've got a 1989 K1500 350 (Transplant, new and balanced) 5 speed (M20), 4X4, 220 TBI (GT4: Rear Axle, 3.73 ratio), with some running issues (new distributer with pickup and module, all new sensors on engine including O2, EXCLUDING, TPS, IAC, MAP, ESC). The VIN indicates that at some point in its life it originally had a V6.

Got an 'ALDU1 and CABL1' from Moates to do some data logging so I can hopefully run down some afterfire/stumble issues. (I haven't checked the fuel pump, which is suspect and next on the list before some serious Timing). Hooked her up and got a good connection, I am using EagleMark's ADX, XDF, and for comparison ASDX 88 C-K Truck 5.7TBI 5 speed manual bin. The current prom is AMUD which appears to be for a 1988 305 manual trans, but was told by a fleet mechanic friend of mine that it shouldn't make any difference (which I kind of question?!) It should be AYUC according to the "BBC" lookup data sheet (thanks by the way for this resource!)


I have data logged a few trips but realized that the results depended on whether I switched the 10 ohm resistor in or out. With it switched on, the idle was significantly higher than when it was off. Is there a preference, since moates says to switch it on and EagleMark says to switch it off? Once I have a definitive answer, I’ll do some more data logging, check the fuel pump, and ask some more questions.


I have some other proms and another 7747 ECM (pulled on my last trip to the yard) to monkey with as required. Is there anyone who could reprogram the appropriate prom for my truck (either the original AYUC or the ASDX 88 C-K Truck 5.7TBI 5 speed manual I found on this site)?


Thanks again for the great resource.