OK. First of all. I'm working on my 88(base model) and I have several head scratchers for you all. I have an Actron OBD I/II with live data readout that I use to get my sensor info from. The car has been doing odd things with idle speed and TPS voltage/position. The TPS is new as well as the ignition module, cam sensor, crank sensor and spark plugs. (The wires ohmed out good so I didn't change them) I'm going to list all the 'Engine Group 1' data that I read after going on a nice highway cruise and got MIL after returning to the highway after a short period of slow stop and go driving in heavy very slow traffic:

2nd GEAR SW: OFF
3RD GEAR SW: OFF
4TH GEAR SW: OFF
AC CLUTCH: OFF
AC HEAD PRES: NORM
AC REQUEST: OFF
BATTERY (V): 13.3
LTFT: 122
LTFT TRCL: 0
BOOST (%): 0
EVAP DUTY (%): 20
EVAP SOLENOID: ON
MIL: OFF ( I did get a code 0123 but I erased it and ignored it)
COOLANT TEMP: 211 (is this normal for these engines?)
EGR REQ (%): 0
EGR VLVPOS (v): 0.7 (this was the same with the engine running and not running. I'm confused as to whether or not it'* working properly)
EGR VLVPOS (%): 0
KS COUNTER: 4
EXH 02: I'm going to say Stoich because it was going back and forth between lean and rich very fast like an A/F ratio gauge would do.
FUEL CUTOFF: NO
IAC POSITION: 44
IDLE REQ RPM: 750
INJ PW (MS): 3.3
STFT: 135 ( I have no idea what my fuel trim is supposed to be at)
KNOCK RET: 0
LOOP STATUS: CLSD
MAF (GR/*): 4
IAT: 136
02S (MV) 60-800 (constantly bouncing)
02S CROSSCNTS 0-3
PNP SW: P/N
PROM ID: 4774
RUN TIME: 15:58
SPARK ADV: 18 deg
THROTTLE (%) 0 (sometimes the idle will go up and this number while physically at 0% will go up to about 7%)
TPS (V): 0.37 (when the above happens, this voltage will also go up to somewhere near .7)
TRANS TEMP: 199
VSS: 0 MPH

Maybe one of you pros can look at my STFT and LTFT and some of the voltages and tell me if things look ok to you. This was written down at idle and everything up to temp.
The car has 209,000 miles on it and I bought it cheap. If there is something major wrong..I will drive it till it quits and buy another $700 beater dh2

Thanks for your input, Terry


edit: hmm, moved eh? https://www.gmforum.com/showthread.php?t=238757 I read the stickies and this should be in the 92-99 thread where it was originally..

I know some of you guys know this fuel trim stuff...come on, help a guy out.

I bought a can of CRC MAF cleaner and it seems to have a bit more power and a smoother idle. I will post later if the idle issue comes back.