Manual Transmission - CAGS solenoid suddenly acting up after years of being tuned out

I recently started experiencing some tune issues (http://www.ls1tech.com/forums/general-maintenance-repairs/1167429-engine-loping-misfiring-lost-power-stuttering-help-please.html) that I resolved with a tune-up. During the course of that, I cleared the codes using an Actron 9185.

Since then I've noticed that, on cold starts, the CAGS solenoid seems to have woken up after being tuned out since before I owned the car (5½ years ago). I start driving and I have only 1st, 4th, 6th, and reverse available to me until the car is completely warmed up. Then it shifts like normal.

WTF is going on? I'm going to do a CAGS delete this weekend with the simple resistor, but I don't know why it would start doing this.

Thoughts?

doesn't quite sound like the cags because that wouldn't disable 5th gear... cags only locks out 2nd and 3rd

Not sure what else to call it. I can sit there with the car off and it shifts just fine. I turn it on and I'm locked out of those gears and it shifts smoothly 1-4. Drive until it's hot and suddenly I get my other gears back, feeling like they normally do.

It popped an SES but I'm betting it will end up being the P0803 code.

Not sure what else to call it. I can sit there with the car off and it shifts just fine. I turn it on and I'm locked out of those gears and it shifts smoothly 1-4. Drive until it's hot and suddenly I get my other gears back, feeling like they normally do.

It popped an SES but I'm betting it will end up being the P0803 code.

Sounds like a clutch related issue to me.

If the clutch is dragging, it typically makes all the gears harder to get into. Do all the other gears feel normal, or do they require increased resistance to engage??

Sounds like a clutch related issue to me.

If the clutch is dragging, it typically makes all the gears harder to get into. Do all the other gears feel normal, or do they require increased resistance to engage??

There is absolutely zero change in the way the car feels when it warms up. It shifts smooth. Even prior to that, going into the gears I'm not locked out of is smooth.

The only recent causes for electrical upset were changing the o2 sensors and when I was driving and discovered a spark plug unplugged (saw weird flickering of the odometer display, numbers glitching and whatnot). I wonder if I bugged out the ECM somehow?

Well, I did the !CAGS mod with the resistor. It took care of the problem, I don't have shifting issues when the car is cold.

Strange thing is, one day later I get a SES light again. I'd bet money that it's P0803 again, but I don't understand why. I think I need to get someone with an ECM tuner on this and re-tune it out again. Something is obviously not right.