something is certainly wrong with the cts reading, not sure how you would tell if something is up with your scanner though unless you found a different one to compare to

I was hoping you would say that. This is the only scanner I found that does OBD 1 & 2. Well, I could buy another car for the cost of a better scanner. The MAF reads 0 @ idle (should be 4- but jumps up with acceleration. I'm suspicious of a few other readings too. The IP Low Coolant warning is on, but the scanner says NO low coolant. The IP light is on with the sensor plugged or unplugged. Between the fishy scanner, half-baked FSM, AND some dude (me) crossing the vac lines, not to mention looking for tools I laid somewhere, I would have been fired or starved to death over this job.

Probably nothing wrong with the P/N switch, because the reverse lights work. Why wouldn't the other gears be accurate?

The smiley should be the number eight.

pnp has separate parts and wires for backup/gear selection/neutral start. the coolant level likely does not go to the pcm. you can check in your FSM. the maf does seem flaky too, not sure i never had a scanner when i had obd1 cars they were many times more than they are now. i know on my cars now my maf readings are around 5gms at idle. cts should just read the temp and not move.

i would have been fired if i had to make my money working on cars for sure, but getting into how it works is how i learn so next time you can remember a certain thing on your car was this was and now its not. or you know how it works so next time you can figure it out easier

OK. That'* good to know. Maybe it'* good that I ordered the P/N switch. I took the wheel off and splash shield to get to the harness and connector and wiggled the wires with the scanner connected and nothing changed. Goes in and out of overdrive 1 or 2 times a second. Connector looked good, tight, & clean. The other gears are weird too - sometimes on/off in 3rd gear; 2nd gear switch always on while in park. FSM says they should be off unless selected.

The CTS & CLS both go into the ECM on this one. Temp. should just be steady temp as you said. I never needed a scanner until this year. I tried an old laptop with software a couple years ago and never could see anything happen. I think I had the wrong bin file. Most of the guys who wrote the software drove different cars than mine.

For now I guess I'll chalk up the MAF, CTS, and low voltage readings and whatever else as bugs in the OBD 1 part of the scanner software/firmware until I start to notice any real performance issues. I might clean my original factory issued MAF and see what happens. Heard some stories on aftermarket MAFs.

It'* good to learn about these new tech cars. Can't complain about learning.
I just sometimes wish that I would learn from a first mistake without doing it again. Might be too far gone for that.

The car has been doing good overall with the few miles I've put on it. Engine runs smooth and has been starting good until I drove 3 miles or so tonight. When I came out of the store, it wouldn't start after 2 tries. On the 3rd try I pressed the gas pedal a little and it started up and ran smooth. Seemed to be idling a little slow, but the engine didn't die on the way home. I've had the throttle body off a few weeks ago to clean it up and I installed a new IAC motor. I think I read somewhere that the low idle screw needs to be adjusted if parts are replaced on the TB. I didn't adjust it and am now wondering if I need to. It has been idling OK until the incident tonight. Weather is a little cooler lately too. No SES light, but I haven't scanned for codes. I probably can't trust some of what the scanner says anyway. Some functions seem to work good on the scanner and some don't. Overall everything seems good on the car except what I mentioned and the Coolant Level light stays on. I've made quite sure there is no air in the cooling system and the coolant level is OK. I even installed my own bleeder petcock on the heater hoses' highest point to make it easier to bleed the air out. The CL light stays on with the sensor plugged or unplugged.

not sure about the idle screw i was under the impression that the iac was only thing involved with idle, did you look in the fsm about what it says to set it at ?

Looking in the FSM, it says when the idle speed is too low, it can be because the IAC motor retracted too much when you shut the engine off the last time. Then when you start the engine the next time, you will be getting too much air past the IAC valve cone. Sooo, in theory, you would need to trick the ECM into adding more fuel to be proportional to the increased air flow by pressing the gas pedal down. That doesn't register in my mind as a reason for the continued low idle once the engine starts unless the IAC is sticking for some reason. The FSM goes on to say: "if there are no vacuum leaks, adjust the low idle screw". I can't remember where I read about adjusting the idle screw after replacing parts on the Throttle body - I'll have to look for it. After cleaning the cone bore seat, I measured the cone distance on the new IAC and it was within specs. Then I reset the IAC per the instructions with the new IAC motor. I'll watch it for a few restart cycles to see if it continues to be a problem.

I don't have a code 35 (Idle Speed control circuit) that I know of, but the info in the pics below help me better understand. I'll post these in case it helps someone else:

Only one pic uploaded. I'll try the other one: