Vacuum Lines / Routing on the Vario Ram System

[TD2015]

Help needed please.

My Greek based mechanic has ordered a new air flow meter for my below par BHP problem but has also asked for any information / diagrams for the vacuum line routing on the Vario Ram System.

Those who have read my RAT posts will know the engine etc was out - the car stripped to the bone - and the mechanic wants to make sure he's rerouted everything correctly.

He still thinks the problem is with the air flow meter but wants to double check that everything has been replaced as per proper Porsche specs.

Does anyone - Maurice? - have a schematic or can scan in something which will help him check that he's put everything back together correctly? The car runs fine - and to be honest I did not notice a lack of power when test driving it - but then it might always have been down on power which would explain that i.e. the air flow meter apparently loses its effect over time rather than works one day, fails the next.

Any advice, help, schematic etc would be much appreciated.

Cheers,

Jon

 

[A Ward]

Hi

Sorry to hear about your problem - just out of interest when you say you are down on power (quite considerably by all accounts) - has your engine been out at any time in the past? I only say this as I had a problem with being down on power and it was because the throttle had been incorrectly fitted in the past and I was only getting 45 degrees of throttle opening - as opposed to the 84 degrees you should have. This would certainly cause you to not have full power - so might be worth seeing if you can connect to the diagnostic port and monitor the throttle angle and wide open throttle position when you press the accelerator pedal (engine doesn't need to be running for this)

With regards to the varioram - when you nail the accelerator to the floor and the rev limiter gets to approx 5200 rpm you should hear a clearly defined note change from the engine. If you are not getting this you could possibly have a failed actuator ram (the actuator unit is not holding vacuum) rather than a routing issue.

The other popular one is the 4 way connector piece that sits to the left of the Varioram inlet manifold located behind the air blower unit and the multiple pipe connection block (gold in colour). The 4 way vacuum pipe connector sometimes collapses (designed as a weak spot in the system) and this can affect the Varioram system.

New actuators for the varioram are between 50 - 75 pounds each and the 4 way connector is approximately 3 pounds. You can test the actuators by removing one of the hoses into the unit and then manually operating the actuator ram into position - then block off the inlet where you removed the hose -if the ram does not remain in the position that you moved it to then it is not holding vacuum and therefore your varioram will not operate correctly as those rams move flaps in the inlet manifold that alter the length of the inlet tract for the varioram to take effect.

Hope that helps - there are also some detailed schematics of the varioram system in the 993 manual which I believe you can download from carnell website.

Good luck

 

[geolab]

I have read all your posts, and am sorry to hear what happened.
But I needed to tell you honestly that I do not trust your mechanic at all.
Just for the fact that he claimed that the fuel pump was misaligned a couple of millimeters, that is why it was humming.
That is a total lie.
The fuel pump is enclosed in a thick black rubber all around.
The pump mounts on rubber gromets, it could never be aligned or less mis-aligned, zero.
Your bill is going rocket high if your mechanic changes parts to new, wild guessing.

here is the diagram you need, just trying to help, regards

http://www.pcarworkshop.com/images/b/bf/Diagram_vacuum_lines_.pdf

 

[A Ward]

Hi

I would seriously get him to check your throttle actuator which has two butterfly valves - if you connect the throttle to the wrong clip section on this housing (which is easily done) then you will only ever get half throttle opening (45 degrees as opposed to 84 degrees) This means that your car would be seriously down on power - although it will still feel quick.

The problem is that when engine is removed the throttle is not easy to clip back in - and often people put it into the cruise control clip of the throttle body which sits lower down than the proper mounting position. I only found this out after my throttle cable snapped and I had to renew it - my brother car had a similar issue with his being fitted to the cruise control clip of the throttle body.

If your mechanic has had the engine out then he would have had to disconnect the throttle and may have fitted it incorrectly when refitting - would definitely reduce your power as the throttle is only ever half open in this situation.

There is an article on the forum under 96 varioram accelerator cable snapped with pictures of the throttle housing - the throttle cable should also be clipped into the highest point of the throttle assembly and not the lower one which is the cruise control connection point (the problem arises as they are both identical so the throttle cable will clip into either)

http://www.porscheclubgbforum.com/tm.asp?m=532925

I suggest you have a read through as if it has been the case on two cars that have had the engine removed - there is every likelihood that yours could be the same. Far better than spending out huge amounts of cash on items you may not actually need.

Regards

 

[TD2015]

Many thanks for the schematic, I'll take it over to Adonis tomorrow.

As for trusting him; he told me he would return the car to its original pristine state which is what he has done re the wiring, the chewed panels etc. He bought all Porsche parts and explained that whilst he could buy a new loom it would be easier to repair the original. Everything works at this point and it was not until he put the car on his rolling road that we noticed the drop in BHP. He believes the problem is the air flow meter but overnight I contacted the UK based Porsche mechanic who serviced the car for me before I picked it up and he mentioned a 993 he'd serviced rcently which also had a significant drop in BHP. In this case it was a problem with the vacuum lines. I mentioned this to Adonis this morning and he asked if I could get a schematic of the lines just in case his mechanic had done something wrong.

As for the fuel pump. He asked me if it had hummed before he got the car and I told him no. He said they must have done something wrong re hooking it back up. The following day I took the car out again and there was no noise from the fuel pump. He said it had been slightly out of alignment i.e. 2mm. He could have told me anything - I'm no mechanic - but to my mind he was honest re the problem and it cost me nothing. He certainly did not replace the pump over night because all parts have had to come from Germany via Porsche in Athens.

Once back in the UK I will get the car checked over by a specialist but I'm betting it will be perfect - as it will have to be for the 2000 mile drive home.

After 8 weeks you get to know someone and he's looked after my car as if it was his own i.e. all the work has been at night with his best mechanic by his side.

Cheers,

Jon

 

[TD2015]

Great advice re the throttle cable linkage - will print off your email and the url and trot over there tomorrow.

Cheers,

Jon

 

[A Ward]

Hi

Picture of throttle clip mounting point on throttle housing shown below - hope that helps make more sense.

 

[A Ward]

also below is the varioram 4 way connector that collapses - shown with heater blower removed, etc...

 

[geolab]

Good to know, trust is the thing.
There are in fact two tricks concerning the throttle cable. One as mentioned very well above concerning the clip,
and one concerning the routing of the cable to the front i:e;
A lot of mechanics drop down the 993 engine, and disconnect the throttle cable from the pedal in the cabin, and not from the throttle body.
There are two holes in all 993 models in the firewall just behind the engine, that route the accelerator cable to the front.
One hole is for tiptronic (thus shorter cable) and other hole is for manual cars
If you are looking at engine from back of car to front, RIGHT hole is tiptronic, LEFT hole is for manual gearbox cars.
if cable is passed in manual passage, the pedal will open half the throttle body as well, to note, regards

 

[TD2015]

Thanks guys,

I've updated this thread on the earlier Rolling Road thread.

Jon