Electrical connection on distributor vacuum hose

Hello, I have a 84 rabbit 1,8 GTI thats not running as good as it is supposed to do. I have checked the cam and ignition timing and found it to be ok (my initial thoughts was that it was one tooth off) the ignition was not pointing directly towards the small groove in the distributor body so I adjusted it to be right in the centre of the "keyway" for the rotor in the shaft. When doing this I found that it was a small vacuum thingy with electrical connection on the vacuum line from the inlet manifold to the vacuum clock on the distributor. Does anyone know what this is? Could a faulty "thingy" cause the car to be powerless? The car pulls strong up to about 4000rpm, then it feels like it wont rev anymore, you could got more rpms but it does feel like it had enough if you know what i mean. See picture.
Next on my list is the famous wur valve and check system pressure from fuel pump.

That is a vacuum operated switch that controls the 'gear change' indicator that will be middle top of your instrument cluster. It plays no part in the running of the engine. I don't know what the internal constuction of it is, but I imagine there is a diaphragm in there that could leak which would stop the vacuum advance from operating as it should. You could try removing it and connecting the pipe direct to the vac advance canister on the distributor.
Once the engine is warm you can disconnect and plug the vac advnace hose and you should hear a diiference in the running of the engine. If there is no difference it could suggest a faulty vac advance canister.
Ideally you want a timing light to set up the ignition timing, this is set with the vac hose disconnected and plugged.

paceman said

That is a vacuum operated switch that controls the 'gear change' indicator that will be middle top of your instrument cluster. It plays no part in the running of the engine. I don't know what the internal constuction of it is, but I imagine there is a diaphragm in there that could leak which would stop the vacuum advance from operating as it should. You could try removing it and connecting the pipe direct to the vac advance canister on the distributor.
Once the engine is warm you can disconnect and plug the vac advnace hose and you should hear a diiference in the running of the engine. If there is no difference it could suggest a faulty vac advance canister.
Ideally you want a timing light to set up the ignition timing, this is set with the vac hose disconnected and plugged.

Hello, and thank you for the info, my car does not have a operational light in the dash anyway so I will try to disconnect it. I have checked the timing advance yesterday by sucking on the hose for the distributor and the internal mechanism moves in the distributor so the diaphragm is working correctly it seems. After setting the ignition to center of the distributor axle to the small groove in the distributor body it was running awful, loads of backfire due to low ignition. I have turned towards more advance and it runs better but need to retard a little more as I hear detonation while on load. my hunt continues

Doing what you are with the timing was the old way of setting it, find a hill that the car has to labour up in third and adjust the timing so you get very very slight detonation, but as paceman says use a timing light, it's the only way.

cedar said

Doing what you are with the timing was the old way of setting it, find a hill that the car has to labour up in third and adjust the timing so you get very very slight detonation, but as paceman says use a timing light, it's the only way.

Hello, I agree, but when not having timing light availible i had to "old school" it. I will check it tonight. Old man, old car here