kkswow12

is there a way to clean the inside/moving parts? my previous post where i discovered the cleaning of the Idle Control Valve makes a big difference in performance, or just general efficiency of the engine makes me think the intake would benefit from being cleaned...does anyone have experience with this, and is there something short of dropping the motor that can be done?....AND if you don't know, clean that ICV with just good ol' brake cleaner and, wow, it is magic, least-wise it was to me...

nk993

last time i cleaned the ICV I used more brake cleaner than the cost of a brand new one. never cleaning it again...buying is easier...and will always work better than a cleaned one.

fatmike

This is a good question.

It's probably worth checking to make sure the varioram is working properly. This one might be more about the function (vacuum lines, actuators, etc) vs. just cleaning like the ICV:

https://rennlist.com/forums/993-foru...s-working.html

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pp000830

Hi KKS,
If all three actuators on the varioram intake cycle when the ignition is first turned on everything is working. The start up cycling is a test the system conducts. If one of them doesn't cycle it is most probabaly a leak in the actuators internal diaphram. The can be tested individually with a short length of hose attached and drawing a vacuum by mouth on the other end of the hose. Taking the intake manafold out and diassembling it to clean it seems to be a sledge hammer solution to a finishing nail enquiery that may introduce other running issues in the process.
Here is a page discussing poor running issues:
https://993servicerepair.blogspot.co...r-robbing.html
Andy

pp000830

Hi NK,
The idle control valve for a 964/993 costs between $400 and $500 and seldom needs to be replaced.
Testing it is easy once it is clean.
The internal butterfly should freely rock/wobble back and forth when the unit is rotated in one's hand
If a 9V transistor battery is attached to the common pin and one of the other pins it will rock in one direction. If attached to the common and the other pin it will rock in the opposite direction.
When installed in the car with the ignition on it should vibrate or make a buzzing sound indicating the Motronic ECU is attached to it.
Andy

kkswow12

i thought i saw from rose passion it was over 600€,,, thats one big box of brake cleaner cans...or? am i looking at the wrong part...

kkswow12

ok i will clean it...worth the hassle removing, well, more's the hassle reinstalling, but still worth it, but seems if that is so gunkerd/carboned up, some of that same !!!! isgetting in the vario tubes, don##t know though having never seen the inner workings...

Cogito_Ergo_Zoom

I'm basically troubleshooting and fixing a lot of vacuum leaks and probably about to remove, clean and rebuild the VarioRam system myself. I found a collapsed rubber vacuum fitting, a bad change-over valve solenoid, cracked intake runner rubber sleeve, and a bad vacuum actuator/capsule on mine and I'm still going. You may find my thread helpful: New 993: VarioRam, Vacuum & other Woes - Rennlist - Porsche Discussion Forums

The ISV can easily be cleaned and tested for proper functionality.

Aardvark123

https://maf-shop.com/shop/iac/porsch...00-0280140543/

Cheaper option. Works fine for me.

Tom

nk993

Yup, that’s the one. Cheaper than brake cleaner more or less

Heuerman

Yes, I bought one from MAF Shop and it works perfectly. I tried cleaning the original and thought it would be OK as a spare but comparing it to the new one (rotate it quickly in your hand) revealed a big difference. After 70,000 miles the bearings are shot.

kkswow12

cleaned it and...!
new car, again..!
i think i will get the replacement from MAF service shop, seems there is a little room for further improvement and they are just up the street, relatively speaking...

boomboomthump

MSRP from Porsche for the Bosch made valve is $800+ but yes, you can get it from Delaware Porsche for about $610 in a Porsche box.

You can also get it in a Bosch box for $200-300. FCP Euro sells it for $205. https://www.fcpeuro.com/products/por...140543#fitment

Overdraft

I remember when I bought my 1997 C4S new in 1997. I had a brochure at the time from the dealer for 1996 model year where they were featuring the new Varioram for 1996 and the salesguy was really fired up about it as well as I recall. Anyway fast forward, I recently bought a 1996 993 which I thought had Varioram in it but the "Varioram" script is not on top of the motor. Is there a difference between years?...any story there or her car doesn't have it :! ?

boomboomthump

The earlier varioram castings did not have the script but there's no difference.

There isn't an exact date it switched over. The later cars had them but there was a transition period in the middle where one car would have it and the next one might not and vice versa. Just whatever was grabbed off the shelf to build your motor.