The 400E has been sitting for about a month (had no time to work on it). I started driving it again this week and a new transmission issue has popped up. It's taking a long time for the transmission to upshift into 3rd and 4th gear. The transmission won't shift into 4th until I get the car up to around 60mph. No hard shifting or slipping occurs. It also downshifts way too easy. I thought it might be the upshift delay relay. I pulled it out and it exhibited the same symptoms when I took it out for a test drive. I'm thinking it might be the upshift delay solenoid on the transmission but the downshifting way too easy is throwing me for a loop.
-
Hi Guest !
Welcome to the 500Eboard forum.
Since its founding in late 2008, 500Eboard has become the leading resource on the Internet for all things related to the Mercedes-Benz 500E and E500. In recent years, we have also expanded to include the 400E and E420 models, which are directly related to the 500E/E500.
We invite you to browse and take advantage of the information and resources here on the site. If you find helpful information, please register for full membership, and you'll find even more resources available. Feel free to ask questions, and make liberal use of the "Search" function to find answers.
We hope you will become an active contributor to the community!
Sincerely,
500Eboard Management
Transmission issue
- Thread starter jgt157
- Start date
Before you do anything ...... CHANGE THE TRANSMISSION FLUID AND FILTER ASAP. 80% likelihood this will solve your problem.
Be sure to drain BOTH the transmission pan and the torque converter. You will need 7.9-8 quarts of ATF. Make sure you use the right stuff. Any Dexron III spec fluid should be fine.
See this post from me, from a few years ago: http://www.500eboard.com/forums/showthread.php?t=3826
Cheers,
Gerry
Be sure to drain BOTH the transmission pan and the torque converter. You will need 7.9-8 quarts of ATF. Make sure you use the right stuff. Any Dexron III spec fluid should be fine.
See this post from me, from a few years ago: http://www.500eboard.com/forums/showthread.php?t=3826
Cheers,
Gerry
Unfortunately, I don't have a good place to do a transmission fluid change. I'll have to take it to somebody to have it done. How hard of a job is it to do the bowden cable adjustment? I think the throttle cable may need to be adjusted too since I replaced the ETA.
Very nice write up on your transmission issue. Can you tell me where the upshift delay is located on these cars? Is it on the firewall in the engine bay or is it on the transmission? I checked my computer codes again yesterday and it was complaining about the upshift delay again (been a constant since I've been checking the codes).
The upshift delay system has several components. The LH module triggers a vacuum solenoid located near the brake booster, and the solenoid sends a vacuum signal down a tube to the Bowden cable assembly located on the transmission. If any of the above items are not working properly, it will trigger a code and eventually trigger the CEL on the dash. Assuming the car is all stock, the most likely culprit is a vacuum issue (broken or loose tube somewhere).
Ok, I think this is the correct component. Let me know if I'm wrong. Here's a picture. I traced the vacuum lines and didn't see any problems. One of the vacuum lines went to the right side of the transmission and I couldn't get to that end. I think the right motor mount is completely collapsed and the was NO room to see or get to that end of vacuum line. I've ordered engine mounts.
While I was under the car, I noticed a wire that ran from the right to the left or visa versa under the engine. It went through a square tube right behind the oil pan. I think the wire color used to be yellow with a green stripe, but not sure of that. The insulation was falling off the wire, Anyone know what this wire is for?
While I was under the car, I noticed a wire that ran from the right to the left or visa versa under the engine. It went through a square tube right behind the oil pan. I think the wire color used to be yellow with a green stripe, but not sure of that. The insulation was falling off the wire, Anyone know what this wire is for?
Attachments
Yes, that is the solenoid which triggers the cold upshift delay.
Was it just the corrugated plastic loom falling off the wire? No bare copper? Sounds like the knock sensor wires to me, and it's common for the loom to break apart. You can break off the old brittle loom and replace it with new split loom of a similar size. I've never seen one with the insulation coming off where it exposes bare copper inside though.
Wow. If you're seeing bare copper... at least wrap it up with electrical tape and maybe put split loom over it. Replacing the knock sensor is NOT fun, as you have to remove both motor mounts+brackets to access the sensor. And it's not cheap. If it's working OK, I'd wrap it and hope for the best...
The upshift delay system has several components. The LH module triggers a vacuum solenoid located near the brake booster, and the solenoid sends a vacuum signal down a tube to the Bowden cable assembly located on the transmission. If any of the above items are not working properly, it will trigger a code and eventually trigger the CEL on the dash. Assuming the car is all stock, the most likely culprit is a vacuum issue (broken or loose tube somewhere).
If I manually apply vacuum, using a hand held vacuum device, should the line running down to the transmission from the upshift delay solenoid hold vacuum?
Yes. If not, something is wrong down there...
Yup, it would not hold any vacuum. I'm glad I found out before taking it in to have the fluid and filter change done. Now I can have him check the end of the vacuum line for me.
Well, we couldn't find any breaks or holes in the vacuum line going from the upshift delay module to the right side of the transmission. I'm assuming that the transmission kickdown needs to be replaced since it won't hold vacuum. Does that sound right? Transmission fluid was replaced and still having the upshift problem.
Your upshift problem is only on the 3-4 upshift, correct? I don't think replacing the Bowden cable assembly (with integrated vac pods) will fix that problem. If it won't hold vacuum, the only side effect should be that there is no cold upshift delay. If all other shifts are normal, I'd suspect a broken spring in the valve body...?
Well, it depends... if you can find a broken spring, then you can try to get a replacement spring from a junkyard VB. Or, swap in a known-good VB. Diagnosing this type of problem is a RPITA.
I'm going to take it to a local import shop to have them check it out before doing anything.Well, it depends... if you can find a broken spring, then you can try to get a replacement spring from a junkyard VB. Or, swap in a known-good VB. Diagnosing this type of problem is a RPITA.
Sent from my VS980 4G using Tapatalk
It's been a while, but, I was able to figure at least one issue with the transmission. The kick down switch was stuck causing part of my problem with the shifting of the transmission. It now shifts from second to third properly, but I'm still having problems with the transmission shifting from third to fourth. It still doesn't want to upshift from third to fourth until the rpms of the engine reach 2500 - 3000. I'm thinking about disconnecting the kick down switch altogether to see if maybe the kick down switch might be bad as well. Thoughts?
It took a year to get the shop to finish this, but the transmission has finally been replaced.
JimT
