850 dies when put in drive, electrical freak out and tranny issues

[chasecar]

Hello MVS! Long time listener, first time caller. I have a 1997 Volvo 850 GLT that is on the fritz. A few weeks ago I replaced the intake manifold gasket to fix an air leak. Drove it home with no issues and parked it for a couple of hours. Then when I drove it next the dash lit up like a Christmas tree and the flashing arrow of death appeared and the tranny was shifting hard and vibrating, didn't feel like limp mode. The headlights and dash lights were also dimming. Parked it and now it dies every time I try to put in in drive. It will go into neutral and shifts hard into reverse. Got it towed to my parents driveway so I could work on it and avoid parking tickets.


I've since replaced the PNP switch and vacuum lines and plan on doing a tranny flush in the next couple of days. I pulled the codes p0740 and p0705. Now when I start the car and turn off the ignition the dash lights all stay on and the engine stays running until I put in in drive or disconnect the battery. I have a feeling this is an electrical problem but am not sure where to start. I believe I may have bumped or unplugged something accidentially when I as working on the intake manifold. Does anyone have any knowledge on TCU and ECU wiring that I can look at? I have noticed that the idle air control valve now buzzes continuously when the battery is connected. (I now leave the battery disconnected when I'm, not working on it) It has a new alternator and new battery. Also, I think the ABS module died. The past couple of months the speedometer has worked intermittently. I've heard that the ECU and TCU communicate through the ABS module. If anyone has any insight or advice I would greatly appreciate it. I've got a new job that requires reliable daily transportation and a baby on the way! THANK YOU!

[ravyngreen]

I have a similar problem with my 97 850t5
But it starts back up after long crank unless you clear flood it smokes white smells like fuel
Does every time I put in drive. Runs perfect in P R ANFD N. cuts out in drive. OBDll says open in injectors 2 ,3,4 5, ???at a loose.