shawscove928s

I have tried the search function, but it didn't find any matches. Which is hard to believe knowing this has been discused so many times on this forum. My search failure is most likely due to operater error on my part.

My 86.5 auto is shifting hard so I want to check the vacume lines to it. The work shop manual diagram shows this line and another going down the drivers side just off center of the back of the engine from the vacume manifold. But my lay out seems to be different. I only see one line going over the bell housing in that location and I think that one is the one connecting to the EZF control. Can one of you please ( Hoefully Roger will chime in too) help me locate the line that goes to the transmission. I have the air box etc. removed and it appears that the trans vacume line is routed towards the pasenger side but dosn't seem to pass over the bell housing or go down the back of the engine.
Thanks in advance.
Ray

Jascd

You may not have the original set up for some reason. On my RHD 89S4 the line goes from a splitter at the rear of the engine, over the bell housing and then is attached to a steel line that is secured to the top of the torque tube. It then leaves the steel line and via another flexible hose enters the modulator on the lefthand side of the transmission. I don't think there is another vacuum line that goes over the bell housing (might be different on your model). Search again and check the spelling of vacuum, that may have been your problem , try "vacuum diagram" or similar. Also check the vacuum from the transmission end with the car running, that will tell you if its connected (expect about 17 inches of mercury at idle) and also check that the modulator holds vacuum. Do that first with the car off and before the exhaust heats up!

G Man

I would check for vac at the input of the vac regulator on the side of the trans to see what you have there. Also use a vac testor on the regulator itself to make sure it will hold vac. I had a hard shift/clunk issue with my 84' and it turns the vac regulator would not hold a vac. New regulator solved the issue. Good luck.

JHowell37

Two vacuum lines go down do and disappear into the depths of the engine. On goes down and makes its way to the right side, through the firewall and into the ignition box. The other goes down and over the bell housing into a steel pipe/tube that runs along the top of the torque tube. From there it goes to the rear, where another flexible line is attached. That line goes to the modulator.

Do a visual inspection of the soft/flexible portions of the line. If the hard plastic line fails and collapses it can seal itself, causing your transmission to not get vacuum. But it can go undetected because there's no vacuum leak. This problem would be more likely to happen near the front where there's more heat.

CJs 928

Ray,

I went through the same thing recently on my 87. Here is a thread that might help you:
https://rennlist.com/forums/928-foru...cuum-line.html

If the link above doesn't work, search for my name (CJs 928) for vacuum line.

Chris