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Transmission shift and reverse problem

Hyundai Accent 2000:, I have been driving w/ the engine light on for a few months, the codes said exhaust leak & speed sensor maybe 2 months ago.

Last night while driving home after being out for about 20 minutes, the car stays in first till I let go of the gas then bumps into second (This is a Automatic Transmission)… I get home and reverse does not engage? So I am guessing the speed sensor, I am going to check the engine code again tomorrow, My mechanic skills are very limited two weeks ago I put in a new Alternator and the week before that a Garage changed my Timing belt and all belts… So, I am reading about a “Pules Generator” also somehow being associated, should this if defective also appear in the code? Should I buy the sensor online or at a dealers? The Hyundai I own had a new engine put in which is a 1.6, normally my car would be a 1.5.



Thanks



Kevin

Kevin…

Start with the basics first…
Did you check the auto tranny fluid level ?
Did you read in the owners’ manual the correct procedure on how to do that? (hint: it’s not just a simple “pull the dipstick” procedure)

With the engine change and the speed sensor code, things could get complicated…Before you buy a speed sensor, you need to learn its location and how difficult it is to replace it…Without input from this sensor, the transmission will get very confused…

I ran the car for 10 minutes till warm and the
transmission oil falls between the two dots that say warm,
about 1/4 of the way up to the top dot like this:

–*--------

Thanks Kevin

At the local parts store they said try
some type of transmission additive.
Because of the discrepancy w/ the
"check engine" gauge it seems to
me it would be electrical in nature.
This is from what I know, very limited

Thank You
Caddyman

Plus, don’t try an additive or you may regret it.

Thanks Caddyman, that makes sense, easy ways out usually for me end in disaster

First of all the reverse problem has NOTHING to do with the speed sensor so if you dont have some sort of linkage problem the transmission will need to come out and be disassembled to repair the reverse problem. Reverse issues are very easy to diagnose. Its either a shift linkage problem or its an internal problem. There is no in between. Either the shift linkage is at fault or the trans comes out. The “Pulse” generator you are talking about reading about is the speed sensor. The speed sensor is an AC voltage generator. Thats how it works, it produces its own AC voltage which sends a signal to the transmission computer. I wouldnt bother replacing the speed sensor now since most likely you are going to have to rebuild the transmission.

STAY AWAY from additives unless directed to by a TRANSMISSION TECH. Some of those additives will only make your problems worse.

transman