Shifting Too Early At WOT

[3400-95-Modified]

It's not really "hidden" or a "flaw" its just a table that no one has mapped out yet because no one cares enough about the older bins to decode them... Trust me I'm in the same boat when it comes to my car going into some sort of PE on the higway at 80... it's NOT good for mileage, there is a table somewhere telling it to do that and I have no access to it.

[Dave96z34]

Its flaw in the 97 pcm that makes it short shift when cold. Its in a hidden table I can't see with DHP tunner or HP.. you may have a relay going bad. There is an extra one on 97s on the drivers side just in case you didn't know.

[Schurkey]

Deleted.

[farley463]

I guess so, lol. I guess the sensor must have thought the compressor was running due to the low/no pressure on the low side, which signaled it to kick on both fans. That sensor must affect a lot because now that I unplugged it, it runs smoother, my PO300 is gone and my SES light turned off. I took it for a drive and now she stays nice and warm, and it sure sounds good screaming at 6500 again. Its a win-win-win!!

[3400-95-Modified]

Well then.... That solves that issue

[farley463]

Well guys I figured it out, it was my A/C Pressure Sensor. I've slowly been getting the parts together to get my A/C working again and remembered that that sensor will kick on both fans if the compressor is running. Unplugged that and now the fans are operating normally again. I have yet to take it for a drive but I imagine it'll be running at 190 again like normal.

[3400-95-Modified]

Scantool.net

I have the OBDLink tool I use to check readyness on various models I have... I use DHP to do my tuning though. OBDWiz seems like a decent program that would let you see some numbers.

Search ebay for a better price if you want.

[farley463]

Alright, sounds like its time to do some digging then. This would probably be much easier to figure out if I had a scanner with datastream so I can watch what the sensor is actually reporting.

[3400-95-Modified]

This is what you need to do... You need to find the problem that's causing the ECU to command the fan on... wiring in a switch is just rigging it to work the way you want, not solving the issue.

Changing to a 195 thermostat for the coolant isn't going to fix the electrical problem in the fan circuitry.

"I" would fix the electrical, see if the coolant thermostat problem doesn't solve itself when the fans work properly. You can always replace the coolant thermostat later, if needed.

And the values I posted are for your 65e... I pulled up a 97 Monte bin file and pulled the numbers from that. Just because it commands a 1-2 shift at 6250 does NOT mean it happens at that RPM It will over shoot, it's called shift delay, and IIRC the MPH and the RPM both have to be met in order for it to shift, unless of course it's going into a limp which is probably what it's doing when its 160*

[farley463]

All shift points for hot and normal RPM WOT related are 6250 in a stock Monte Bin... So yeah no idea why your having the issue you are.

The speed points are 42 for 1-2 and 80 for 2-3... Are you reaching those speeds before the RPM value? I can't remember which one is priority.

If it's shifting normal once the temp was passed 160, that's a bit odd but the ECU could have been locking it in a open loop mode somehow.

Hmm. The tables might be different with a 65e instead of a 60e, because before I ripped it apart to get the trans rebuilt it would always wind out to 6500. My first to second shift would occur around 45-50ish and it would go into 3rd at exactly 90mph. I don't know what's causing the fans to be on all the time. I put a good working ECT in my parts car and I'm still having that problem. I did install a 195 stat in it today and it seems like now it will warm up to about 200, it will shift normally, then the thermostat will open, it'll drop down to 160, then it'll short shift again. If I unplug the primary fan it will stay at 190 so I'm starting to think about running one of my switches on my center console to power one of the fans instead of having them run constantly. Any ideas?

[3400-95-Modified]

All shift points for hot and normal RPM WOT related are 6250 in a stock Monte Bin... So yeah no idea why your having the issue you are.

The speed points are 42 for 1-2 and 80 for 2-3... Are you reaching those speeds before the RPM value? I can't remember which one is priority.

If it's shifting normal once the temp was passed 160, that's a bit odd but the ECU could have been locking it in a open loop mode somehow.

[Schurkey]

Changing to a 195 thermostat for the coolant isn't going to fix the electrical problem in the fan circuitry.

"I" would fix the electrical, see if the coolant thermostat problem doesn't solve itself when the fans work properly. You can always replace the coolant thermostat later, if needed.

[farley463]

Well I put a good ETC on from my parts car and the fans still run at all times, so I pulled the plug for the primary fan, took it for a drive and she got up to 190 and started shifting like normal again. I'm picking up a 195 stat for it and I'm gonna swap that out tomorrow. I think the one in there now isn't right for the engine.

[farley463]

Yeah I just got mine rebuilt after I blew it up doing reverse donuts. That was a 600 dollar mistake that ill never make again. Anyways ill try that. One thing I did notice is that even when its cold, when I first start it up both fans immediately kick on. Maybe I should unplug one and go for a drive. Sound like a bad ECT?

[Dave96z34]

160deg is low let the car sit and get hot an do a hole shot tell me what happens.

284 is cool but a built 4t65 is the way to go. Im burning threw clutches one every 2 years none supercharged.