Your 1988 Dodge Colt Vista Wagon has a 2liter motor and a 5 speed transmission everything works well except the gear ratio between 4and5 is the same is there a shift solinoid in the transmission?

Answer 1

Dodge ColtI have the same car and had the same problem not to long ago. there are a few things that could be wrong for your specific problem. there is no solinoid in the transmission but shifting from 4th gear to 5th gear is complicated on this car. when you move the shifter from 4th to 5th, a switch on the linkage that activates a relay that turns on a eletric motor that changes the direction of a vacum which operates a acuator that gives you 5th gear. the switch is on the shift linkage where it hooks up to the transmission, its round with two wires. you can check it by opening the hood and turing the ignition on, move the shifter from nuetral to 5th, you should be able to hear a clicking noise, if you dont its probably the switch or the relay. if you do hear a clicking noise, then check you vacum acuator, its near the front of the transmission on the passenger side of the car, its skinny and round with two vacum hoses. you can remove it and directly connect a vacum to it and see if it is operating properly. be sure to mark all your hoses and install them back in order. if your vacum acuator works and you hear the cliking noise then it may be the electric motor, its on the top of the transmssion on the passenger side, it has 3 vacum hoses and two wires. if you have the all wheel drive model then its the one closer to the front of the car, if yours is 2 wheel drive its the only one. remove it and hook it up directly to 12 volts to see if it is working properly. make sure all your vacum hoses are in good condition and not leaking and check all your electrical connections. I apoligize for the long awnser, but hopefully it helps you and saves you money.

There are two vacuum canisters outside the tranny where you can get at them. One is the 4th-5th (overdrive) shift and the other operates the transfer case for 2/4WD. Sometimes when they get old, they leak; it is one of the freguent problems with Colt Vistas. As of 2008, these units seem not to be available from Chrysler (USA), but very possibly you can repair yours, even if you don't have much mechanical experience.

Have someone with a vacuum pump (Mityvac is a common brand and not terribly expensive) test the canisters to see if they do leak. After removing a bad canister, you'll see that it is built in two stamped halves. Gently pry back the tabs that hold the halves together. With the canister open, gently work the rubber diaphragm loose. If the rubber is "rotten" and cracked, you probably can't save the unit, and need to find one in a juckyard with a better-looking diaphragm. Clean any crud off the good diaphragm, especially around the edges which must get a good seal against the case halves. You might want to clean the rubber with a whitewall tire and rubber cleaners such as Bleche-Wite, and when it's dry, treat with a tire protectant or maybe Armor-All. Remove the rust form inside the case halves, particularly where they seal against the lip of the rubber diaphragm. The best way to do this is to have a local auto machine shop blast it with glass bead. With it clean, you could prime and paint the case halves inside and out to prevent more rust. But make sure you don't get a lot of paint in the critical sealing area around the inside periphery of the case halves. With everything clean and dry, you're ready to seal and re-assemble the unit. With your (clean, non-oily) fingertip, spread a thin layer of RTV silicone sealant on the outside edge of the rubber diaphragm; put a thin layer on the periphery of the case halves where the diaphragm must seal. And, crucially, work some silicone sealer down into the center of the diaphragm around the metal stem, both sides. Let the silicone seal set up for a few minutes, then set the diaphragm into the case, set the halves of the case together, and gently bend the retaining tabs back in place. Don't pull a vacuum on the canister for an hour or so, to let the sealant cure; then test it to see how you did.

The same moisture that rusted the vacuum canisters and compromised the original seal can also cause problems with the vacuum solenoids that route the vacuum to the canisters. These can also be rebuilt at home, but are a rather more delicate procedure. If you want to try it, take the solenoid apart very slowly, taking notes or making drawings of the tiny valves, seals, and springs (which tend to jump out). This is pretty close work, better suited to a watch repairman than a hammer-and-tongs mechanic. For more info on Colt Vista issues, try www.coltvista.com