Sorry for the long post but it is very important

My 2000 Grand Caravan SE has been having some troubles lately. It has 209K miles on it and the engine runs great. Im a high school student and i use my school's auto servicing lab to fix up my car. Great opportunity to learn.

Just about a week ago i noticed that the tranny was shifting a little hard. I thought it was just cold until it warmed and started really shifting hard to where the van would lurch forward when it upshifted. Downshifting was fine, it was the upshifts that had trouble. the worst shifts were from 1 to 2 and from 2 to 3, occasionally doing it into 4th.

Jacked the van up on the lift, dropped the pan and changed the filter and fixed a couple leaks with some gasket sealant. Poured 4 quarts back in and added a torque converter instant shudder fix. Drove it for a couple miles and it seemed to fix it until it warmed up fully and the shifting got worse.

Let it sit in the driveway for a couple hours to let it cool off and drove it back to the shop where i use the lift. The van clunked into gear and would consistently lurch when going into gear. After a while the van was stuck in second gear and as i've heard on other forums "limp mode". Got it back to the shop and shut it off It smelled hot (almost like it was burning), checked the fluid, the level was fine but it was dark red (had a slight burned twinge to it). The check engine light was on.

Hooked up the scan tool to it today and even with the check engine light on, there was no error code that came up when we searched the engine and tranny codes. Only had it running for a few minutes to check the level and the scan tool said that the tranny was well over 1000 degrees (whether that is correct or not, there's no way to tell)

I'm at my wits end. I had the shift solenoid and the input and output sensors replaced just last year so it doesn't make sense that they'd fail now. There was no diagnostic codes or anything.

Please help me out here. The auto shop teacher doesn't know what's wrong with it and my family needs this van to function properly. We depended on this vehicle to get us around and I need to get it fixed up and properly. We do not have the money to take it to a professional shop and spend thousands on a van that is only worth $800 blue book.

Thanks in advance and have a good day

 

What was the code for the check engine light? Then with scanner, can you tell me the controller number and the CVI's. Also if you can perform a clutch test and a shift lever test. To me it sound like you may need overhaul the transmission, seals and clutches. But need the information first.

 

I am currently unable to run any codes because the engine is half apart while I'm replacing the valve covers and I disconnected the negative cable from the battery. Will give an update on the engine code as soon as everything's done with the engine and I can turn it back on safely.

 

Ran the codes. Three total...

P1784--Low Reserve Pressure Switch

P1787--Overdrive Hydraulic Pressure Switch Circuit

P1782-- 2-4 Pressure Switch Circuit

How would I go about replacing these? I am able to buy a new transmission for $200, and install it myself with the help of a few others. Yes I know it will be a lot of work, but I need this van. Just buy the transmission for $200????