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Interestingly the Throttle Switch claims to be made in Germany, but the Knock Sensors are made in Romania
Prices seemed very reasonable, at £52 and £22 x 2, p&p inc
Hopefully this will regain me some lost power, as the car is currently struggling to get over 150
I haven't put a JDS tester on the car to check for faulty sensors, so it could still be a faulty Hall Sensor
However at those prices it seemed the right thing to do, as the last time I changed a knock sensor was about 15 years ago
Fuel injectors have all been cleaned, so I'm struggling to think of another possible cause of the power loss, not that the car feels slow, but objectively it is
Interestingly the Throttle Switch claims to be made in Germany, but the Knock Sensors are made in Romania
Prices seemed very reasonable, at £52 and £22 x 2, p&p inc
Hopefully this will regain me some lost power, as the car is currently struggling to get over 150
I haven't put a JDS tester on the car to check for faulty sensors, so it could still be a faulty Hall Sensor
However at those prices it seemed the right thing to do, as the last time I changed a knock sensor was about 15 years ago
Fuel injectors have all been cleaned, so I'm struggling to think of another possible cause of the power loss, not that the car feels slow, but objectively it is
The throttle switch full open contact tells the LH brain to go full enrichment for power and the max power ignition advance maps. If that contact is not working you will lose some top end but checking that contact for function is very easy. You clearly understand the function of the sensors and the Hall trigger and changing those elements out pre-emptively is never a bad thing. Thus if you are going to pull the inlet manifold might as well do the things captive to that operation. The Hall trigger is a separate activity.
Having a tool to check the operation of these things is a bit of a must have- I use my ST2 in that regard.
The throttle switch full open contact tells the LH brain to go full enrichment for power and the max power ignition advance maps. If that contact is not working you will lose some top end but checking that contact for function is very easy.
Yes but I don't trust components to work the same when you test them, as under real world conditions with high under bonnet temps
I am hoping that the switch is at fault, as I was foolish enough (and money was tight) to fit a used switch just 12 months ago
Yes but I don't trust components to work the same when you test them, as under real world conditions with high under bonnet temps
I am hoping that the switch is at fault, as I was foolish enough (and money was tight) to fit a used switch just 12 months ago
Another reason why ST2 is very useful as one can monitor in real time what is working [or not] on the engine. I have always opined that the flappy should have an indication whether it is working. For a while I ran with a vac gauge on the HVAC vac system to test whether the vacuum was holding up over a run [it was]. If the vacuum holds then it is a fair bet the flappy will be operational. Still some kind of position indication to give positive feedback of the thing would be a useful addition over and above the buttometer that has been known to let me down.
Another reason why ST2 is very useful as one can monitor in real time what is working [or not] on the engine. I have always opined that the flappy should have an indication whether it is working. For a while I ran with a vac gauge on the HVAC vac system to test whether the vacuum was holding up over a run [it was]. If the vacuum holds then it is a fair bet the flappy will be operational. Still some kind of position indication to give positive feedback of the thing would be a useful addition over and above the buttometer that has been known to let me down.
The flappy does have such an indication. It runs a test cycle every time the engine is started. If you remove the rubber cover it’s easy to see whether it’s working, and only slightly more difficult if you leave the cover on, but stick a piece of tape on it. This will test both integrity of secondary vacuum system, and integrity of flappy vac actuator itself.
The flappy does have such an indication. It runs a test cycle every time the engine is started. If you remove the rubber cover it’s easy to see whether it’s working, and only slightly more difficult if you leave the cover on, but stick a piece of tape on it. This will test both integrity of secondary vacuum system, and integrity of flappy vac actuator itself.
That just tells you it is working when you start up and is a two man operation type of thing.
What I feel might have been warranted in the original build is some kind of real time direct indication that the vac system is viable and that the flappy operation is in play and responding- something like the PSD lamp but direct feedback from the shaft movement.
That just tells you it is working when you start up and is a two man operation type of thing.
What I feel might have been warranted in the original build is some kind of real time direct indication that the vac system is viable and that the flappy operation is in play and responding- something like the PSD lamp but direct feedback from the shaft movement.
Sure it's not a perfect test, but if it works on start-up (and that's quite demanding, as relies on vac reservoir being ok) then I can't think of any likely circumstances which would stop it working at 4000rpm, since the LH will send the same signal at 4000rpm that it sends for the test cycle. You'd convince me if there were some experiences of the system working on test, but failing in 'real world' (but I also take your point Fred that it's hard to be sure it works in real world other than using the seat of the pants test gear!). I have faith that Porsche engineers would not have included that test if they didn't think it would be a reliable test of the system, but this all becomes philosophical.
At least if it fails on test, it's never going to work at the real trigger point, so you'd learn something valuable in that case.
I would also suggest to replace the flappy and throttle shaft bearings,
adding new seals will reduce false air and prevent the new TPS from filling up with oil.
I am doing an intake refresh and i took the TPS off and it had oil in the connector pin area.
I sat it on a table in the sun with the shaft opening down and left it for a few hours,
when I came back a large stream of oil had run out of the TPS unit.
I put the new double sealed shaft bearings in
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Power Loss - Knock Sensors?
