My '98 (W code) has 115k miles on it. I changed the trans fluid and filter within the last 6 months. Transmission shifts fine when underway, but recently the transmission is slow to engage when first shifted from Park to Drive (engine and trans cold). If I hurry the shift right after the engine fires up the trans does not engage and the engine rev's without making forward progress. If I wait a few seconds the trans engages and works fine. The delay is getting worse as the weather gets colder. Is this torque converter related, vacuum related, or something else? I'd like to fix this before it gets worse or fails completely!

I'm not sure what linkages or devices are used to get the trans in Drive. I checked the vacuum canister under the battery and it's working fine (free and operating). Any other ideas?

Thanks in advance, oh...and I searched this site for related problems and didn't find any. Sorry if I've duplicated another posting.

 

Does the condition change if you let the vehicle warm up for a bit before engaging the transmission?

There are no external devices other than the shift cable that controls the gear selection in the transmission. Everything is inside the transmission.

 

Yes, I only notice the problem when starting up first thing. If I rush (and who isn't in a rush?) and shift from Park to Drive immediately after the engine starts the trans does not engage. If I wait a few seconds it engages and shifts just fine. I'll state the obvious...just wait a few seconds and drive off. But the issue is it's getting worse and I'd rather fix it now before I get stranded somewhere.
By the way, the trans fluid was changed when I did the filter and gasket. No burning or discoloration was noted then, and the new fluid is topped off and clean. I'm beginning to think the torque converter may be draining a bit...any possibility?

Based on your reply I can rule out vacuum and external devices. Thanks again for the very prompt reply.

 

It could be a check valve sticking open allowing the torque converter to partially drain back to the pan. I had this happen on my old '97 Dodge Ram. A bottle of Lucas Transfix and a few weeks of driving and it was back to proper operation.

 

Hmmm, sounds like snake oil, but I've got nothing to lose. I'll try it and post a message if there's any change to the way things are operating. Thanks again for your advice!