FYI An insidious potential power robbing vacuum leak you may have and are unaware of.
11-02-2015, 03:39 PM
#1
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FYI An insidious potential power robbing vacuum leak you may have and are unaware of.
Last edited by pp000830; 01-24-2021 at 02:01 PM.
11-02-2015, 06:02 PM
#3
There are 5 of those suckers on a vram 993, 4 if you have the RS(3c) heat/freshair mod.
I had a vacuum leak at #32, heater flap under the dash. It cost an actual measured on a dyno 50hp loss.
The best way to find the leaks is to smoke the intake tract
Any of those little rubber conectors can also add to the vacuum loss
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max911 (06-21-2022)
11-02-2015, 09:33 PM
#4
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[QUOTE=Bill Verburg;12723769]
There are 5 of those suckers on a vram 993, /QUOTE]
Where is actuator 3b?, can I see it in plain sight?
Thanks,
Andy
There are 5 of those suckers on a vram 993, /QUOTE]
Where is actuator 3b?, can I see it in plain sight?
Thanks,
Andy
11-02-2015, 09:46 PM
#5
Banned
I Have replaced a few in the past.
My car through codes 80 / 208 resulting in Pinging = Power Loss
Stage 2 V ram became inoperable in my case.
If memory serves I believe the original part went through a re-design.
Result is that the New Part is potentially stronger. I am sure others will chime in.
Keep me in the Loop. Thanks for sharing!
Good Info about the dash Loss of 50 HP
TJ
My car through codes 80 / 208 resulting in Pinging = Power Loss
Stage 2 V ram became inoperable in my case.
If memory serves I believe the original part went through a re-design.
Result is that the New Part is potentially stronger. I am sure others will chime in.
Keep me in the Loop. Thanks for sharing!
Good Info about the dash Loss of 50 HP
TJ
11-03-2015, 12:08 AM
#6
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[QUOTE=pp000830;12724466]Can't miss it, there are three on the varioram manifold, two are topside, and that one is toward the bottom and offset to the left / driver's side - roughly at the center of the pic below.
Last edited by bcameron59; 11-03-2015 at 12:14 AM. Reason: Add pic
11-03-2015, 12:24 AM
#7
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Great markups on the diagram btw, wish I had this when I was reassembling vacuum lines after doing my top end rebuild last year.
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11-03-2015, 03:45 AM
#8
Drifting
I can confirm that at 120kmi, I had 2 of these vacuum actuator's that were leaking (heater/fan box and left side bottom VarioRam actuator). Those were relatively quick/easy to fix. I still need to replace the 3rd one on the back top right of the engine and the other type/partNumber top left....oh, and possibly the one Bill V had issues with under the dash as well. Add it to the list... 
If things look like in bcameron59's pic, the varioRam flap oil leak is obvious. One would want to do the replacement on the 2 VarioRam seals:
https://rennlist.com/forums/993-foru...-manifold.html
If things look like in bcameron59's pic, the varioRam flap oil leak is obvious. One would want to do the replacement on the 2 VarioRam seals:
https://rennlist.com/forums/993-foru...-manifold.html
11-03-2015, 04:07 AM
#9
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Yeah, that pic was taken before I fixed the gasket and shaft seal - it's a TCM 8x12x3vc lip seal.
No oil leaks from the vram now. Also helps if you don't overfill the oil so it doesn't get sucked into the intake...
No oil leaks from the vram now. Also helps if you don't overfill the oil so it doesn't get sucked into the intake...
11-03-2015, 08:45 AM
#10
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11-03-2015, 10:32 AM
#11
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If I recall rightly, you'll have to pull off the resonator flap assembly before you can detach the vacuum valve, which is unbolted from the bottom of the varioram. It is a tight fit but do-able, see the thread that kjr914 linked to for some tips on how to this.
It helps to undo the short rubber connectors between the varioram and the intake manifolds (where the fuel injectors plug in). Might also help to loosen off the engine mounts and lower the engine a couple of inches (supported by a jack of course). These steps will allow you raise the vram to improve access.
It helps to undo the short rubber connectors between the varioram and the intake manifolds (where the fuel injectors plug in). Might also help to loosen off the engine mounts and lower the engine a couple of inches (supported by a jack of course). These steps will allow you raise the vram to improve access.
11-03-2015, 11:29 AM
#12
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Need help in finding the heater flap under dash
Here is a vacuum actuator part of a Flap Assembly part number 993.572.077.00 part of the HVAC system behind/under the dash, I think it is called out as #32 in Bill Verburg's illustration. Does anyone know where to look under the dash for this thing exactly?
11-03-2015, 12:31 PM
#13
Three Wheelin'
I have an obvious question. Did you notice the power drop right away and is that what tipped you off?
Maybe that is why my car is so slow.
--Michael
Maybe that is why my car is so slow.
--Michael
The two 993.110.462.02 vacuum actuators on the intake if purchase under the Porsche number are very expensive even on-line. When they fail (leak) it looks like they must cause a manifold leak, no good can come from this.
I checked the actuators by disconnecting them and sucking on the air line that feeds them, lots of air draw, no movement.
Turns out that Pierberg, the supplier also supplies the same part to BMW under part number 11617786961 or 7786961. I ordered two at the BMW dealer for $40.80 each, who would think the dealer would be the best buy!
The third actuator on the intake manifold for the Verioram 993.110.462.02 seems to be of a different design that is more robust.
I checked that actuator by putting a piece of tape on the actuator's arm in such a way that it would be pulled off if the actuator's arm moves. I revved the engine and checked the tape and it did pull off. My assumption is that if the diaphragm in the actuator was torn even a little it would not actuate so it seems to be good-to-go as is.
Andy
I checked the actuators by disconnecting them and sucking on the air line that feeds them, lots of air draw, no movement.
Turns out that Pierberg, the supplier also supplies the same part to BMW under part number 11617786961 or 7786961. I ordered two at the BMW dealer for $40.80 each, who would think the dealer would be the best buy!
The third actuator on the intake manifold for the Verioram 993.110.462.02 seems to be of a different design that is more robust.
I checked that actuator by putting a piece of tape on the actuator's arm in such a way that it would be pulled off if the actuator's arm moves. I revved the engine and checked the tape and it did pull off. My assumption is that if the diaphragm in the actuator was torn even a little it would not actuate so it seems to be good-to-go as is.
Andy
11-03-2015, 01:16 PM
#14
The latest actuators appear to use silicone diaphragms (vs. rubber in the originals), easy to tell as they are whitish vs. the black originals. I think the actuator arms are molded in a single piece vs. the threaded adjustable arms in the originals too. No difference to function except that you can't swap them around anymore as the arms are different lengths on a couple of them.
The one on the heater blower is the same as one of the engine mounted actuators, I'd replace those (especially the one under the intake manifold) if they're original and you have the engine out for any reason. Save the good ones for the eventual heater blower &/or recirc door replacement.
Should also test the check valves (#8 in diagram) near the 'vacuum tree' behind the engine mounted blower fan.
11-03-2015, 01:39 PM
#15
Three Wheelin'
Has anyone ever done a smoke test on a VRAM 993, ideally with a DIY smoke source? Would love to know any best practices on how to seal up the intake, where best to introduce the smoke, and where all to check.
I'm sure one of us could do some trial and error here, but curious if anyone has been down this road before.
I'm sure one of us could do some trial and error here, but curious if anyone has been down this road before.