1998 Mercury Mystique transmission problems

[fatjoey666]

I need some good advice. My 1998 Mystique, 4 cyl. Zetec 3.0 Auto transmission, has a serious tranny problem. It started with the O/D light flashing, then it started slipping in D. I could still drive it, but I would have to start off in 2 and get it up to 3500 RPM's and then I could put it in D and it would shift fine from there on out. Now, all forward gears are gone, but I still have reverse. BUT if I put the car in D it will creep forward, but it will rev up with no movement. I tried unhooking the MLPS plug with no effect. Could someone please tell me if they think this is Transmission bands, Torque converter, or something else entirely. I am going to fix it but I would like to know where to start.

All help and advice are greatly appretiated. Thank You!

 

[andreslobo]

Smell your oil

Smell your oil

From the description of your problems, the very first thing I would do is to look and and smell the transmission oil. If it is brown AND smells burnt, you have burned out clutches which required cracking the transmisson and replacing most seals, frictions, steels, and for good measure the oil filter and band.

If the oil smells burned and you are going to rebuild, do some data gathering before you pull the transmission. For certain plug an oil gage into the plug on the oil pump end of the transmission located it the drivers wheel well. Record the oil pressure in all gears. If the oil pressure is low it might indicate a bad oil pump, or the seals you will replace.

 

[amc49]

When the forward clutch snap ring grenades its' groove and pieces start coming off, can act like that. Forward clutches then start working their way out of drum. At first forward gears will work somewhat but later all forward drive disappears. When happens, may not have much burned fluid at all, depends on how much time spent abusing clutch pack that won't lock up. If that's what happened get ready to replace lots of parts. There is nowhere for broken pieces to go but through several other rotating parts before bits get free to be caught by magnet. Could be something as simple as blown piston seal too though, that would not damage so many parts.

 

[fatjoey666]

thank you for the info. I checked the fluid, it is a little brown but does not smell burnt at all. I never heard a sound when it started going out. I did replace the shift before all this trouble started and had to wire the O/D which runs through the shift. It costs $180 for a transmission rebuld kit from Autozone. Does that include the bands and all I need? It's a headache to yank the tranny, but I guess I don't have much of a choice.

 

[andreslobo]

do some more trouble shooting

do some more trouble shooting

If the trans oil is not burnt, you should do some more troubleshooting before you decide you need to pull the trans. Oil pressures in all gears is a good start. Checking your trans sensors as well. From your description it sounded like burnt clutches but absence the smell of burnt trans oil (get a few opinions on the smell, maybe your nose is not up to snuff) you have some other issue that you should identify before tearing into it.

 

[fatjoey666]

That's what I keep thinking also. It just went out all of a sudden and I never heard any noises or experienced anything strange. I am just a backyard mechanic, so I need help on how to check the oil pressure and everything you think might benefit me. I have the Haynes manual. Which sensors should I check? You are right about the burnt smell. I will have someone else smell it. Thank You for all your help and advice!:shrug:

 

[andreslobo]

AMC 49 is probably on target

AMC 49 is probably on target

If your failure was sudden, then AMC49 is probably right on the money, and it likely tore up the inside of your trans, but you never really know until you tear it apart. But is the car worth a rebuilt trans ($1,200)? If not, no need in spreading the parts all over the place.

The question should NOT be, 'can I do it', but should be, 'should I do it?'

 

[amc49]

That very last sentence says it all. I am a mech and it was quite a bit of work. Also, no rebuild kit will cover all the shells/drive cylinders you may damage. Mine ran perfect until one day on decel down freeway exit ramp it suddenly acted like someone slammed down hard on the brakes. No OD light, no noise, but no gears either. At first had second but not first, drove home 50 miles in second and third, started losing them toward the end. Still no noise, oil clean and red, no metal particles in it. At home no forward drive at all, just reverse. Besides kit I replaced 5 major cylinders. The magnet in these things is awesome, virtually everything caught by it, you should have seen how much there was. Unfortunately, pieces of debris have to go through all the rotating parts before they can get to magnet. Mucho damage results. Mine still running 2 years later after rebuild. I spent $600 in parts but as prissy as I am, I know for sure it would have cost me $3500 to have someone rebuild like I did. I freshened up everything, if it doesn't last 7-8 years I will be pissed.