I have a 91 Caravan LE with the 3.3 liter engine and the A604/41TE 4 speed transmission.
Not long ago I had the struts replaced on my van and when the mechanic removed the passenger side strut it pulled the drive axle out of the transmission and it leaked a little transmission fluid, the amount of leakage was minimal so I never thought much about it. But now last Wed. morning on my way to work as soon as I started to accelerate on the turnpike the transmission dropped out of high gear, I noticed my RPM's up to over 5000 and only doing 70MPH, I immediately let off the gas to drop the RPM's down to under 4000 and by doing this I was able to maintain a speed of about 45 to 50, I drove at this speed all the way back home (about 15 to 20 miles). I checked the fluid level when I got home and it did not register on the dip stick so I put 2 quarts in and that topped it off again. I then took off again and as soon as I got on the hwy. it started doing the same thing would not shift out of low gear. So I drove it back home again about 5 miles this time or less). I had pulled both input and output speed sensors and took them to Auto Zone to have them checked, they tested good. My check engine light never came on. Any suggestions on what the problem may be, thanks.

 

That old of a van does not have any check engine to transmission related codes.
I didn't know autozone had the capacity to test the sensors???.

The only way to really know what's wrong is to get a scanner that will connect to the blue diagnostic connector under the dash on the driver side usually near the fuse block.

 

The 1991 vans have two connectors for checking codes. The connector under the hood is for the SBEC or PCM.There is another under the dash(blue), That one is for the transmission and ABS if you have ABS. And the air bag module.You would need a scanner that can read the early CCD buss system, Like a DRB2 or DRB3 with an early supercard. If you had to add 2 qts of fluid, I would ck for any leaks. Once you have the codes, post them so we can help.

 

Yes Auto Zone does have a tester for these sensors. http://www.autozone.com/autozone/par.../N-j8ocfZ6o3b6
Isn't this blue connector the same one that reads out the computer codes? The engine codes can be read by turning the engine on, off, on, off, on. But there is no code for transmission problems. Where could I get this scanner to plug into the blue connector and what codes does it read from.

 

The blue connector will get the information from the ABS module and the air bag module and the transmission module. Thats all. The connector get the information from just the PCM module, And yes you can cycle the key 3 times to get just engine codes. If you know someone with a DRB3 or a good snap on scanner.

 

There are at least 8 different quality scanners that can read the transmission information thru the blue connector and Autozone does NOT have anything that can connect to the BLUE connector. There are no engine codes thru the blue connector. The master stated that ONLY ABS, Air Bag, and Transmission codes come thru the Blue connector. You can key cycle for engine codes all day for the next 100 years and you'll never get any trans codes doing that. The key cycle is ONLY for engine codes on your vehicle. There are NO transmission codes thru the key cycle method on your vehicle. The minimal trans codes using key cycle did NOT start until 1996 for vans. The ONLY way to find out why your transmission isn't working is if you can find a quality scanner, have it connected to the BLUE connector under the dash and access the Transmission Control Module.

All your link shows is they sell the sensors not that they can test them. I don't see any tooling showing the ability to accurately test the sensor. I'd like to know how they "tested" your sensor. The Autozone by me had no way of testing sensors off the vehicle.

Hey Master Tech, what's the difference between a Good snap-on scanner and a not so good one?

 

Better Snap-on gets you the chicks the not so good one....well you get all the leftovers

Hey Master Tech, what's the difference between a Good snap-on scanner and a not so good one? [/quote]

 

If you check in the add under Notes this is what it says:
Notes:
Input sideTo test->locate test chart "SU17" in Wells test manual
They have a Wells tester with a manual for testing the sensors. I cannot say as to any accuracy of this tester but they do have the tester and their test showed the sensors as good.
And yes it has already been determined that the check engine light does not give any transmission diagnostic codes, I first asked that question about the blue connector before I realized they had two different connectors. The only thing I am still needing advice on at this point is where I can get a device to check the transmission codes through this blue connector? You say there are 8 different quality scanners that will do this, but where can I get one? What do I need to look for and at what price range just to get something to check the codes? I was checking ebay for this MT2500 scanner and I find items such as http://cgi.ebay.com/SNAP-MT2500-TROU...item4157549d44 for as little as 19.99 and ranging all the way up to items like this http://cgi.ebay.com/Snapon-Modis-Sca...item3f07fe1015
for 6500.00. Obviously I would not need all of the equipment that comes with the 6500.00 price, but what would I need to look for to get just the minimum of what I need?

 

We recently purchased a 2002 Dodge caravan sport and it is burning gas like crazy. The problem is the tranny is not shifting into the higher gears. Okay driving around the city, but.... places I have to go require less travel time by highway. I don't think its coming out of 2nd. What could be the fix?

 

Dude you are describing the classic "limp mode" senario. If your van does not have any power leaving a red light - even if you stomp it to the floor - and has to wind its way up to 40mph and never changes gears, then you need to have your tranny replaced and it usually costs about $3200 or more depending on where you have it done.