Alfa Pages

[92P4]

Hi chaps

Great page, came across here about 5 years ago when I had my last P4 and got a bit side tracked by Lancias for a while when the old girl packed up.

Decided today to take on a 73k 1992 OK condition Permanent 4 with an irritating problem!

When I picked up the car the 4wheel drive was working fine - ignition on, 'ping' from the EM coupling, great 4wd there, well happy. Bit later on in the da (Driven 350 miles today having fun!) 4wd decides it doesn't want to work any more!

When switching on the ignition, I hear the 'ping' then a second or so later, a click as the EM coupling disengages again! I would assume the light would come on at this stage, but the bulb appears to have blown (or been taken out!)

When it was working the 4x4 was fine - no knocks from the VC, and great on fast roundabouts

Any ideas of what to look for? The only two suggestions I have come across from reading others misfortunes have been the switch on the brake pedal, and the wiring under the console, neither of which I have checked yet.

The car had a flat battery when I went to pick it up despite the battery being new (My last P4 went flat after 3 days with a new battery too, any suggestions?)

Sorry this post is so long, hope someone can help!

Cheers

Gord

[92P4]

Right, checked the switches on the pedal, the 4x4 one WAS stuck in the 'brakes off' position which is now fixed. However... Its still exactly the same - except when I turn on the ignition with the pedal down, the EMC doesn't engage and disengage - but its still coming on then off when not on the pedal.

Any suggestions of where to look next? Don't have a clue myself

[tvatavuk]

Let put it this way: No bulb no 4x4.
If only one light goes out, 4x4 will not engage, and there are two in series. So question now is, do you have 4x4 warrining light on first few seconds you start ignition?

If you have multimeter check that that both switches are working, and that they click at same time.
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Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

[92P4]

The funny thing is that there WAS 4x4, but now there isn't! The light hasn't come on at all, not even for the second or two when it should at startup. Is there a cutout if the light doesn't work then? Are both the bulbs in the instrument binnacle? I've got a copy of ePer - should be able to source the part codes if thats likely to be what it is

[tvatavuk]

Yes there is cutout, if there is no power (closed circuit) coming from 4x4 warning light, 4x4 computer at back will turn complete 4x4 off.
You might also check all fuses in fuse box and 4x4 just for fun to see if allare ok.
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Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

[92P4]

OK. Is there anything else thats common other than the brake switch and the bulbs? Had exact same symptoms on my last P4. Will get a pair of bulbs at the weekend

G

[tvatavuk]

Somewhat common problem for 4x4 is toothmesh sensor, in and of gearbox el. coupling. But it has nothing to do with bulbs going off permanently.
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Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

[paulhide]

Not totally sure, but I think that there is also a relay with a fuse in it.
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Owner's Club 33 Registrar. Now from P4 & S2 1.7 QV
http://www.alfa-pages.co.uk/viewtopic.php?t=5188

[tvatavuk]

Yes there is, he probably checked fuse on it by now, but it would made 4x4 warning bulbs light up. At least it does so if there is no fuse or no relay.
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Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

[92P4]

Well I know the bulb is defo not working, I will fix that, the fuses are fine. As I said, the el mag coupling can be heard to click on and then off before even starting the engine. It was working fine though, and the bulbs weren't working then either! How would I ge to the toothmesh sensor if that could be what it is if replacing the bulbs doesn't work? Could be a loose wire quite easily I would guess?

[paulhide]

Of course there is the 4WD ECU in the back and you should check the heavy duty black wire coming from in front of the gearstick to the couple which may, as I have seen in one case, come free and be worn to the inner metal.
_________________
Owner's Club 33 Registrar. Now from P4 & S2 1.7 QV
http://www.alfa-pages.co.uk/viewtopic.php?t=5188

[tvatavuk]

If you had 4x4 and warning blubs were off all time, then probably previous owner replaced blusbs with wire or something. As I said 4x4 should disengage completly off if there is even one burned blub.
If placing blubs that light up, and taking care of connectors on intrument panel cluster doesn't help.
First next thing to check up would be those brake switches, that both work and they click at same time.
If that checks ok,
next is checking wiring from underside black wire for tooth mesh sensor, thicker red? wire for el coupling, there was case that prop shaft got hold of that wire and made mess of it, but it resulted in burned out 4x4 fuse under bonnet.
It all wires are ok, check that tooth mesh sensor has short circuit with multimeter or resistance with ohmmeter. tooth mesh sensor is in fact microphone (coil type) so there must not be any breaks. Conectors for tooth mesh and el. coupling are behind ash tray or around gearstick in cabin.
There are also two 4x4 conectors from memory I think one is 4 other is 6 pin type, you can check and maybe clean contacts.
But I suggest you first take care of blubs, and then take it step by step with gudiance one of many 4x4 gurus here
If back of your car is swimming pool, and 4x4 ECU is taking diving leasons that would be good reason for dodgy working.
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Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

[paulhide]

Very neat and concise Tino Yeah red wire not black underneath.
_________________
Owner's Club 33 Registrar. Now from P4 & S2 1.7 QV
http://www.alfa-pages.co.uk/viewtopic.php?t=5188