CD4E/ Blinking Overdrive Light

[DanMystique]

I have a 96 Mystique GS with 169K miles original Eng & Tranny with no major problems up until now, i was driving down the street and the car wouldn't shift from first to second so i gave it hell and it shifted real hard and the OD light started blinking so i drove it down the highway and it wouldn't shift into overdrive whats up with it i have alot of experience with cars and i think its the shift solenoid anyone with the same problem i need some input

 

[Tony2005]

Welcome . What was the speedometer doing when this happened? If it was going crazy, then you need to change the Vehicle Speed Sensor tomorrow.
http://www.contour.org/ceg-vb/showthread.php?t=1816&highlight=vehicle+speed+sensor

In any case, when was the last time you changed the ATFluid? If more than 2 years or 20k miles, try that first. Also check to see if it is low on fluid now.

ATFLuid change in Duratec Maintenance-Read First
http://www.contour.org/ubbthreads/s...992476&page=0&view=collapsed&sb=5&o=7&fpart=1

 

[projectSHO89]

A fluid change at this point would be a waste of perfectly good fluid.

Pull your codes FIRST.

You might have something easy to repair such as a MLPS fault, something Fords are well known for.

Failure to follow the factory diagnostic procedure almost guarantees you'll be wrong.

Steve

 

[DanMystique]

Cd4e

Cd4e

The Speedometer reads fine, I changed the Tranny Fluid 10k miles ago, the tranny worked fine up until this happened it never slipped and shifted gears just fine, I think when i pull the engine to rebuild i'll rebuild the tranny as well but i'll diagnose it first so i'll know what it is

 

[unisys12]

Dan, don't forget to check the CD4E FAQ's I had posted on the old forums. Here ya go! http://www.contour.org/ubbthreads/s...655008&page=0&view=collapsed&sb=5&o=7&fpart=1

Anyway, it will be hard to tell exactly what's going on. You could possibly find out by performing pressure tests on the valve body, but in most cases it will lead you to a general area. Most likely though, the 1-2 shift valve (driven by the 1-2 shift solenoid) became stuck in the bore of the valve body.

One question though... Does it still shift harshly? Also, does the O/D light still flash when the tranny should shift into overdrive?

If it does still shift harshly, then you probably blew a seal when the valve stuck. And if the O/D light still blinks when the car should be shifting into overdrive, then you most likely have an electrical (sensor) problem.

(I cover the following in my FAQ's, but it's worth covering again)
As for the O/D light and getting the codes... Unless the check engine light is on and it "stays on", you will have to use a pretty decent scanner to pull the codes.

See, if the O/D light blinks that means the PCM has detected a problem with the tranny. There is a code present at that time, but will not be stored into memory. When this happens, the PCM puts the tranny into what is called, "limp mode" or "safe mode". In this state, the PCM ups the line pressure to a default level of 110psi no matter what. This will enduce very hard shifts. When this happens, you will find that you can pull over and turn the key off. Restart the car and "Wa LA!" the problem is gone. Well, it is, until the PCM detects the problem again.

Now, if the CEL comes on and stays on, then you can use a simple scanner (such as those used at Autozone or any other parts store) to pull the code. But remember... The CEL has to stay on, even after turning the car off and back on.


As for rebuilding the tranny... If you are comfortable with rebuilding ATX's then you could do it for around $1500. Give or take. Check out BT's rebuild... http://www.contour.org/ubbthreads/s...531563&page=0&view=collapsed&sb=5&o=7&fpart=1

 

[DanMystique]

Well i found away to limp around, i'll manually shift into first and let the speed get around 20mph and let off and shift from first to drive and it'll shift only when there is no load and when it shifts into 3rd on its own i kick the Overdrive off otherwise it will blink at 35mph because it wants to go into od, GHETTO MYSTIQUE untill i get the fundage to do a rebuild, does anyone make any stronger than stock parts for the CD4E?

 

[unisys12]

... does anyone make any stronger than stock parts for the CD4E?

Well, not really stronger, but better designed - yes. Look for a valve body that has been rebuilt with Sonnax parts. Other than that, OEM stuff is fine. When I had mine rebuilt, I had the valve body rebuilt with all avaliable Sonnax parts and Raybestos clutch packs.

Now, you can get almost all your parts from a single source, such as www.bulkpart.com and the such. One thing to watch, when it comes to shopping. You will come across a TransGo shift kit. This kit is not a performance kit, but a shift correction kit that can correct runaway line pressure such as you are probably experiencing. If you are going to perform a complete rebuild though, I would suggest going with the Sonnax parts instead of the TransGo parts. The Sonnax parts are far , but the TransGo is fine to get you by. Tons of tranny shops use them. I am going to dig around on the old forums because there was a place I used to refer a bunch of people to where you could get a rebuilt and fluid tested CD4E valve body for around $200. Complete with all Sonnax parts. I will find it tonight and post it here for ya.

The CD4E's weakness is in the valve body. Add to that poor maintaince and you have a serious problem on your hands. By replacing the valve body with a properly built unit and combine that with regular fluid changes. You will have a rock solid perfoming tranny. Will it be a road race monster? No! It wasn't designed for that, but it will be reliable.

 

[DanMystique]

Thanks, this tranny has been tooken care of all its life, my father owned the car before i know it was well maintained, Im surprised this tranny has lasted 169K miles good tranny