Modulated transmission?

Angel · Post by **Angel** » February 23rd, 2006, 10:33 am

Hi all, I have a problem with my car that I think might be transmission related, I have described the problem in my last post in :

http://www.mx-3.com/phpbb2/viewtopic.ph ... 3&start=15

I've been doing a little research and I came upon what is called a vacuum modulator which if faulty could produce the symptoms I have, the problem is I dont even know if all cars have this of if my 1995 MX-3 has it. I've checked the online manual but couldn't find it. Now could this modulator be the cause of my problems ?

My symptoms are :

Erratic gear shifts, car stays in lower gears , abrupt gear shifts , leaking fluid toward the front driver side, i think this is transmission fluid.

Any help is appreciated,
- Angel

Tunes67 · Post by **Tunes67** » February 23rd, 2006, 11:25 am

I am pretty certain that our cars ATX trans dont have vacuum modulators. Our transmissions are electronically shifted. Vacuum modulators are used in transmissions that are not electronically shifted to tell when to shift the transmission based on the vacuum levels in the engine. As for the fluid leaking out... What color is the fluid? If it is red.. it is transmission fluid (or it could be a dark green if someone filled your tranny with B&M Trick Shift transmission fluid). Your symptoms are similar to mine, with the exception of the leak, when my transmission filter was in dire need of being changed. If the fluid is tranny fluid... there are only a couple of places it could be coming from. Around the transmission fluid pan, The tranny cooler lines that lead from the transmission to the radiator (there are 2 lines... one takes the fluid to the radiator and one is the return line). Possible but unlikely places it could be leaking from would be the radiator, torque converter (this would be VERY messy if it happened) and possibly around the axle seals. Now if one of your tranny cooler lines has ruptured.. it could also cause symptoms as you have mentioned. But I think I would first check the filter in the trans and the seal around the tranny pan. You can get a new filter from napa auto parts for less than $20 US. Hope this helps.

Tunes67

Angel · Post by **Angel** » February 23rd, 2006, 1:48 pm

Thanks Tunes, I am definitely bleeding transmission oil , it's leaking from the driver side at the very front of the car, since i'm certain it's leaking fluid should I skip the transmission filter change (although I'm pretty sure I need one) ? ... ....Is there a manual that shows how to check/change the tranmission cooler lines? I think this could be quite possible considering how close to the front the leak is. However since I am not really sure where it's leaking ...how expensive would be to replace the seal around the pan, or any seal for the matter, I hear it's a pretty expensive repair?

...I took the car to a Mazda dealership (I got sick of the dirty garages) and they want to charge $41 for a diagnostic alone, and waive this charge if I repair with them but I'm pretty sure they'll sneak in the $41 and then some, I don't want to get f'd in the A ...I think I've done about $400 in repairs the last few months and even got a new set of tires which makes it very tempting to keep pumping dough in the car but I'm thiking I may just cash in before my mx-3 drills new holes in my pocket and maybe put the cash forward for a new mazda 3.

Tunes67 · Post by **Tunes67** » February 23rd, 2006, 2:01 pm

it's leaking from the driver side at the very front of the car

This is exactly where the tranny pan is located.. if its a large spill its most likely from the seal around the pan.. if it was your lines.. it would likely be a few small spots rather than a puddle. You can get a standard tranny maintenance package from your local Minute Lube, Jiffy Lube, or Grease Monkey. They usually cost $100-$150.. This usually includes a new filter, new seal for the pan and a fluid change. If you decide to go this route its important to tell them you DO NOT want a Power Flush. Long story as to why not.. but there are several recorded incidents of almost immediate ATX failure in our cars after having a Power Flush service done. In your shoes.. If I couldnt do the work myself.. I would take it to a Minute Lube and have them check under the car for you. They will be able to find the leak.. and it will cost a whole lot less than the Mazda Dealership. Before you go though.. make sure you put more tranny fluid in.. if you run your tranny dry.. you will cause major damage.

Another option.. but I have no idea how much this would cost. If you dont want to move your car.. there are mobile mechanics that will come to you and do the work for you. Dont let them supply parts for you though.. from what I have heard they will charge a lot extra just to run to a parts store for you. The cheapest solution here would be to do the work yourself if you can. Will cost less than $20 to buy a filter kit (it comes with a seal) from a parts store. Good luck.

Tunes67

Tunes67 · Post by **Tunes67** » February 23rd, 2006, 2:06 pm

Oh and yes there is a online shop manual that will give you complete instructions on how to do both the tranny filter & pan seal as well as show you where the tranny lines are. The online shop manual is located off the main http://www.mx-3.com home page. In the column on the left a little ways down. Conveniently enough for you.. the shop manual that is there is also for the 95 model year of the MX-3. So it will be exactly what you need for your car (its pretty close for other years as well). Cheers

Tunes67

Angel · Post by **Angel** » February 23rd, 2006, 11:42 pm

Thanks Tunes, I think I found the procedure in the online manual but I think it's rather vague or it's just completely over my head. Anyways, would this repair require taking down the tranny? if so thats way out of my league.

Tunes67 · Post by **Tunes67** » February 24th, 2006, 12:30 am

You mean replacing the pan seal? No.. that doesnt require removing the transmission. Its actually pretty straight forward. Jack the car up and put it on jack stands. There is a plastic shroud you will need to remove to access the bottom of the tranny pan. Once the shroud is removed. You will need to remove a cross brace or cross member.. its 4 bolts. It blocks access to a few of the bolts that hold the tranny pan in place. Then you just remove about 20 small bolts from around the tranny pan itself. Be careful as you do this.. loosen one corner up completely... then slowly loosen the bolts away from the corner you loosened up completely. Dont back the bolts out all the way.. loosen only a couple of turns and have a catch pan positioned under the corner you loosened up completely.. The result will be that the corner you loosened up the most will slowly dip downward and dump any remaining tranny fluid into your catch pan. The only reason I say be careful is because if your like me.. you WILL spill tranny fluid all over the place.. LOL Yeah.. doesnt matter how careful I am.. I usually make quite the mess when I do this. Once the pan is off.. remove all traces of the previous seal from the pan edge and from the bottom of the transmission. There are 3 bolts that hold the tranny filter in place. Remove those bolts and pull down the filter. There is a wire that runs across the filter that you will need to slide out of your way to drop the filter down. Then place in your new filter and replace the bolts. Make sure you have the pan and the bottom of the tranny completely clean of tranny fluid before you reassemble.. I like to use shop rags and alcohol to make sure the surfaces are clean and dry. Then just reassemble. Make sure you follow the torque specs in the shop manual.. be careful not to over tighten the bolts or you will get leaks down the road. One thing I do with any tranny pan I ever have to touch is put in a drain plug. Usually you can find a drain plug kit at a parts store and if installing it requires tools you dont have.. a machine shop can do it dirt cheap for you. Also a good idea.. place a couple of magnets in the pan prior to putting it back in place. This helps catch small metallic particulates and prevents them from circulating through your tranny.

I know this sounds a bit complicated... but I think you are more than capable of doing this job... it can be messy.. but its really just taking bolts out and putting them back in. Just let me know if you have any questions. Btw.. if you get the drain plug installed in the pan.. you dont have to take the pan down again when you change your tranny fluid. Makes changing your tranny fluid a lot less messy

Cheers

Tunes67

Angel · Post by **Angel** » February 26th, 2006, 8:30 pm

Thanks Tunes, I'll see if next weekend I find the tools to do this, seems pretty straightfoward , in the mean time i'm using a loner. Btw is changing the transmission filter a must or just a do-it-while-im-at-it sort of thing?

A million thanks to you!

Tunes67 · Post by **Tunes67** » February 26th, 2006, 11:21 pm

No sweat.. glad to be of help.. it is pretty much a "must do" thing for our ATX cars. Especially if you recently aquired the car.. you dont know when last it was done.. and its far far better to just do it than hope the previous owner kept up on the maintenance. Our tranny fluid is supposed to be changed fairly frequently.. every 10k miles if I recall correctly. Which is why I recommend getting a drain plug installed in the pan

Not sure how often the filter is supposed to be changed.. but they are cheap and it cant hurt to toss one in once a year. If you read through the Automatic Transmission forum.. you will see a LOT of accounts of dead ATX trannies in these cars. Once I saw that.. I assumed a better safe than dead type of attitude. I know of a couple of ATX cars that have had proper maintenance that are approaching 200k miles and going strong. I just bought a 92 GS car with an ATX tranny.. guess what I bought at my local napa store today.. you got it.. A tranny filter, and fresh ATF fluid. I would add a tranny cooler to it as well (and this is highly recommended for any ATX car really.. especially if you drive it a lot or drive it hard) but for my GS.. the car isnt going to be driven much and I only need the ATX to live long enough for me to get all the parts to do a MTX swap.

Yeah if you are going to get down there and replace the seal.. do the filter as well.. its cheap and only 3 more bolts to take out and put back in. One tip though.. on the filters you will see a black O-ring that seats into the valve body of the tranny (you will recognize it when you see it dont worry) before you put the new filter in place.. wet the O-ring with a bit of ATF fluid.. then just push it up into place and replace the bolts. This coming weekend I will be doing everything I just mentioned too you to my GS. Its a different tranny than you have since its a V6 car... but I can take pics if you want so you can get a general idea of what it all looks like. Cheers

Tunes67