QuestionCAN YOU TELL ME WHERE THE VACCUMN HOSE IS LOCATED ON THE POWER BOOSTER?? WHERE IS FUEL FILTER AT? IS THIS SOMETHING I CAN DO?? FLUID LEVEL IS FINE AND NICE COLOR, NO DARKNESS OR AIR BUBBLES, DOESN'T SMELL BURNT. IS THERE A FILTER IN TRANSMISSION THAT MAY BE PLUGGED OR A LINE?? ITS LIKE I HAVE TO GIVE HIGH RPMS TO GET IT TO MOVE, LIKE ITS NOT PICKING UP FLUID, BUT ONCE IT STARTS TO GO, I AM OKAY, TO YOU, DOES THIS SOUND LIKE TRANSMISSION IS DAMAGED OR JUST NEEDS EMPTIED AND NEW FLUID?? THANK YOU FOR ALL YOUR HELP.
hugecatfish@yahoo.com
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The text above is a follow-up to ...
-----Question-----
JUST STARTED DOING. WHEN I START IT UP AND PUT IN GEAR TO MOVE, I HAVE TO EITHER BACK UP AND GO FOREWORD TO GET TRANSMISSION TO PICK UP. ONCE I AM GOING, IT SHIFTS AT ALL STAGES CORRECTLY. NOW, SOMETIMES AT A LIGHT, I HAVE TO GIVE MORE R.P.M.S., TO MOVE, MORE OFTEN THASN NOT I DON'T.
IT SEEMS LIKE ITS NOT PICKING UP FLUID AT THE START?? DO THESE VANS HAVE A MODULATION VALVE, MODULATOR??
ALSO. SOME TIMES IT WILL HIT HARD AT A SHIFT, SO, I STOP VAN AND SHUT OFF, WAIT A MINTUE OR TWO, START UP AND GO AND IT SHIFTS OKAY AGAIN??? I HAVE A POWER BOOSTER THAT NEEDS CHANGED OUT AND YOU CAN HEAR AIR WHEN PUCH ON PEDAL, WOULD THIS(IF IT IS) VACCUMN LINE INTERRUP TRANSMISSON OPERATION?? I AM AT A LOSS. I WOULD GREATLY APPRECIATE ANY AND ALL HELP WITH THIS. I AM A CANCER PATIENT AND HAVE LIMITED FUNDS, BUT I NEED TO GET BACK AND FORTH TO HOSPITAL FOR TREATMENTS. THANK YOU
ALSO, DOES THIS POST ON THIS WEB SITE OR CAN YOU SEND ME ANY IDEAS TO MY E-MAIL: hugecatfish@yahoo.com
-----Answer-----
On a 99, to the best of my knowledge, there is no vacuum modulator.
But a vacuum leak could have an effect on the shifting due to ECM readings.
I assume fluid level and condition is fine.
I would repair the vacuum leak.
But you could unplug the hose to the vacuum booster, and plug the end of the hose, just to see if the low vacuum is the culprit, keeping in mind all the time that you will have non power brakes during that period.
But if it stops the problem with the shifting, you know that replacing the booster will fix it.
That same type symptoms can happen with a dirty fuel filter, but it isn't the fuel causing the problem, it is the lack of power. The vacuum leak could do the same, and since it is often right when the brakes are applied, sure would make me lean that direction.
Van
AnswerHello Jim,
There is a filter in the transmission, but if the fluid looks clean, I would doubt it is plugged up.
There is also a tube from the filter to the housing, and a seal where that tube pushes into the housing usually.
On an older vehicle, I would say there is a possibility that seal had hardened and is allowing air to pass, which would act like yours does, but on a 99 I wouldn't expect that.
Still, a fluid and filter change would not hurt it, and might just correct the problem.
I would always do that myself, rather than have one of those quick change oil change shops do it.
A dealership would be ok though. But make sure you insist on them dropping the pan and changing it. Don't let them talk you into the "suck it out" method. That does NOT get all the fluid, it does NOT get the filter changed, and it does NOT get a leaky seal replaced.
Also, when you drop the pan yourself, you can look in it to see what kind of stuff might be laying in the bottom.
The power booster....
It is the large round thing the brake master cylinder is mounted to, and there is a large hose connected to it, usually with a elbow that pushes into a large grommet.
The elbow is also a check valve to keep the vacuum in the booster when engine vacuum drops, such as when the engine is shut off, or dies, or when going up a steep hill.
Vacuum booster were replaced on some light trucks with a Hydrovac unit, which uses power steering pressure for brake assist, rather than vacuum, but I don't think your van would have that.
Van
