Hi Everyone,
I have a 1996 "N" registed VW Golf 1.8SE with the ADZ engine and single-point Bosch Monotronic fuel injection. Yesterday, I took it to my local independent garage for its annual service, and I mentioned to the proprietor that it was pinking on acceleration (and I don't use supermarket petrol).
I got a call from him a couple of hours later, stating that the timing was out, which had caused the pinking. Apparently, when the engine is at Top Dead Centre, the rotor arm should line up with a groove in the top of the distributor, and on my car it didn't.
Anyway, when I collected the car and drove it home, it felt somewhat funny. The pinking was gone, but the idle speed was up from 800rpm to 1000 rpm (not adjustable on Mono-tronic), and the engine seems louder. On checking with my Haynes manual, it states that the timing is set for the life of the vehicle at the factory, and it shouldn't be altered, in fact it warns that there are no timing marks on the crankshaft pulley to do this with. So I had a thought. The car had its cambelt changed at the same garage last year, so I'm wondering if during that time, with the belt off, the auxiliary shaft which drives the distributor from the timing belt moved, hence this time around the rotor arm isn't pointing at the TDC mark anymore. Having now moved my distributor (which the mechanic states was seized in place - factory anti-tamper seal possibly), does this now mean that my engine is correctly timed, or are there other parts in my distributor which is confusing my ECU even more?
The guy who does my servicing is very honest and reasonable, and has always made a very good job of my cars before. But like everyone, he is human and humans do make mistakes. If I went back to him with some feedback that what he'd done was wrong, he'd be happy to put it right I'm sure.
Any suggestions?
Steve
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Well, for starters you don't set the ignition timing by aligning a rotor arm with a mark!
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Well DL is right as the dist/shaft is indirect the timing can be adjusted but not by lining up the rotor arm to distributer.could and may well cause more problems.what should have been done is the camshaft/aligned /crank/aligned/then aux/shaft then fit the cambelt only a slight alteration needed then for correct ignition timing.if any.I did one a few months ago but an earlier model no marks at all.works fine.
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Thanks guys. I'm still a bit confused...
I can see the bit in the workshop manual where it says to line up the middle of the rotor arm with a mark on the distributor. If the camshaft and crankshaft sprockets were both aligned correctly, but the auxilary shaft was out hence the need to rotate the distributor to line up the rotor arm with the scribed mark, would the system be timed correctly? Put it another way, if the car had a conventional Hall effect distributor, it wouldn't matter a fig about the position of the auxilary shaft, because you could then time up the engine dynamically using a timing strobe on No 1 HT lead and pointing it at a mark on the crankshaft pulley, while rotating the distributor. My Golf has got engine management to control ignition advance/retard - hence no handy markings on the crankshaft pulley.
Thanks again,
Steve
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Just throw my sixpen'orth in here. There is always a bit of a grey area here but I think youll find that there is still a hall effect trigger in the dis but the advance is controlled by the map in the ECU. However base timing is critical but as Mr Haynes says it is factory set and the dis is tamperproofed. The pinking should be contained by the knock sensor. Sounds like your man has unwittingly changed the base idle setting by beating off the metal antitamper fitting on the dis to "correct" the timing. No matter because there will always be the timing marks on the flywheel which Mr Haynes has forgotten about or you could move the dis back to its original position as there will be a 'witness' on the dis clamp from its original position.Also I'd get someone with the knowledge to check the knock sensor output.
Andrew
Simplicate and add lightness!!
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Thanks Andrew. My car doesn't have a knock sensor - I think that was only fitted to multi-point fuel injection models. Can you tell me a bit more about these timing marks on the flywheel? How do I access them and can I then time up the engine dynamically using a strobe light?
Thanks,
Steve
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I would strip the covers off and check the belt tension and the cam to crank alignment. The aux sheft is not driven by the cam belt but driven from the crank If all is well and I suspect it is not then back to garage. Regards Peter
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If you look on the top of the gearbox adjacent to the engine block you will see a plastic plug covering a hole. Pop out this plug and also unscrew the large hexagonal plastic bit as well (for better access and with a bit of imagination you will see a sort of pointer which you use as a timing mark cut into the upper edge of the aperture.I am going to check up the procedure for resetting base timing.
Andrew.
Simplicate and add lightness!!
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