88 S4 in first wont rev past 4100 rpm...?
 

My 88, S4 when in first with the pedal to the floor will not go beyond 4100rpm, it shifts to second. Second and Third gear got beyond 5500RPM with no issue...?

Also sometimes or most of the time I dont feel like I am getting 100% out of the throttle, I checked the idle click and that seems ok but have not done the WOT test...is there an easy way to do this...? It just seems to pull slow at times, it revs in 2-4 gear just slowly at times...?

any thoughts...? One issue is one of my oil breather hoses has ruptured...could this be a possible culprit...?

thanks...

I had something similar on an '85; at speed (65) it had no accel, flooring it in 4th or 5th would do nothing. Turned out to be corrosion on a coil wire.

You can test out your throttle switch by disconnecting the LH & EZK plugs. Check this thread for details. It has tons of info!

https://rennlist.com/forums/928-foru...LH+diagnostics


I too would also recommend checking for corrosion on the coil wires and inspect the distributor caps & rotors.


EDIT: After seeing Jim's post, this may be the more reasonable cause of your problems. Also, is your kickdown cable slacked?

The auto trans has no brains so must rely on mechanical inputs to determine how it shifts. Vacuum is one input and the pressure cable from the side of the intake is another. If your throttle cable has stretched or missadjusted and you are not getting full movement then the pressure cable is not telling the transmission that you have the pedal floored. Not knowing what you want to do the trans will shift early and smoothly since you are not in any hurry.....

First, check the adjustment of the cable from the throttle pedal to the quadrant. You are aiming for somewhere between almost zero slack but zero pre-load.

Next, check the adjustment on the cable from the quadrant to the throttle body. Again, just a tiny bit of slack. Check for the throttle switch click that should happen as soon as you move the throttle pedal. Check for wide-open throttle. Check the closing of the WOT switch at about two-thirds throttle. No click - you have to check at the ECU connector. You can check the idle switch at the same time.

The cruise control cable should always have some slack.

Under the car on the driver's side of the transmission, find the vacuum modulator. Check for full manifold vacuum - measure the vacuum at the manifold (make sure that you are measuring raw manifold vacuum - no check valves or boosters), then measure the vacuum at the hose at the modulator. The readings should be the same. If not, fix the leak.

With the car in a quiet place, turn the ignition switch on and roll down the widows. Push the throttle to the floor and listen for the click from under the car at full throttle. This is the kick-down solenoid. The kick-down solenoid activation makes the transmission more reluctant to upshift, more anxious to downshift.

When these are correct, start adjusting the transmission cable. Tighten a little, drive for a couple of days. Repeat until you like the speeds at which the transmission shifts.

If necessary, adjust the modulator to soften or firm up the shifts. The cable adjusts shift speed, the modulator adjusts shift firmness.