Maestro won't start

[RobertP]

My latest acquisition, the aptly-named Angina (1.3 1984) is causing me extreme grief. For the first few weeks I had her, no problems. Then gradually it took longer and longer to start. It seemed like a car with manual choke trying to start without using the choke. I have read many threads here about the stepper motor playing up so on Sunday I removed it (quite easily). The o-rings look perfect. I used electrical cleaning spray on the multiplug, and also on the fuel ecu behind the driver's shelf. I put in new plugs and leads, cleaned the rotor arm, and reassembled everything. Started perfectly. This was worrying, as I didn't know what I had cured! Since then, though, the problem has re-occurred. Flooring the accelerator and just turning the engine over will eventually work, but only with a fully charged battery. There is supposed (according to Haynes) to be an ambient air temperature sensor but I can't see it. Is it likely to be the stepper motor, the ecu, the wiring/plugs, the air sensor, or perhaps something else entirely? I am seriously contemplating replacing the carb with one from my manual choke 1993 Maestro, but that will never really tell me whatwas wrong. Can anyone tell me what should happen to the stepper motor when it is cold and the ignition is turned on? There is a rubber grommet with a little peg sticking out. Is this the clue? What should happen to that, and how can I test it?
After the RAC started me yesterday (just with jump leads) I didn't dare turn it off, and left it ticking over for an hour. Lovely heater! But fuel consumption must be in single figures.
I have tried a couple of local garages, choosing those where the mechanics are middle-aged, but they don't want to know.

[MaestroTurbo]

You should have replaced the seals as you may have damaged them again by refitting. If they sit flush with the brass emulsion tube they will leak fuel. The rubber grommet with a rod sticking out is the fast idle advance, it must move when cold and ignition activated otherwise the car will stall and flood.

[G Force]

Hi Robert, Im fairly sure we should be able to sort out the problem without resorting to the manual choke route.

You ask what should happen with the stepper motor when cold, Quite simply when you turn on the ignition from cold you should see the stepper motor pin extend from the boot about 4 to 5 mm and if things are adjusted correctly you should see the throttle linkage move as a result of the pin moving.

You mention high fuel consumption, not too sure if you meant because of having to leave it running for long periods, but first thing to check with bad starting and high fuel consumption would be the the vacuum switch, the small unit connected on the side of the carb by two small pipes and with a vacuum pipe connected. Remove the vacuum switch and suck on the vacuum port, if you can suck through it then it is faulty and needs renewing.

Dont worry about the ambient temp sensor it only plays a very minor role in the auto choke, it definitely wont be that. It is in the loom behind the n/s headlamp on the inner wing.

For testing the stepper motor other than when cold It would be easier to explain a method if you can say whether the fuel ecu is part no. ADU 6553 or ADU 8494 as the method is slightly different for each.

[RobertP]

Thanks for the replies. I shan't be able to do much till Saturday (it's not only freezing, it's also covered in snow). I'll check the ecu type then. If the stepper motor isn't sending its little prod out, is it likely to be faulty, or is it more likely to be that power isn't reaching it? My electrical expertise is very basic, I'm afraid.

[G Force]

If the stepper motor isn't sending its little prod out, is it likely to be faulty, or is it more likely to be that power isn't reaching it? My electrical expertise is very basic, I'm afraid.

Hi Robert I would say that if the stepper motor does not move then 9 times out of 10 it will be wiring, then the coolant sensor or ECU. Dont forget to check the vacuum switch and check the ORFCO is not stuck open check in FAQs for info on how to check these.

Regards Gary :)

[ChrisM]

Hi Robert. Sorry to hear you're having problems... :o

I remember when I first got the car, I had similar problems. In the end, it took a new ECU. This was brand new, so I doubt it is at fault here. What I would recommend, though, is taking the ECU out from behind the dash and cleaning up the contacts on it, I bet this is where the electrical fault is, probably due to that leaky grommet that caused the water intake!

Hope you get it sorted soon. At least your heater works well, mine broke yesterday!

Regards,
Chris

[RobertP]

Hi Chris, good to hear from you.
When I got home yesterday (very cold, getting dark) I checked the action of the stepper motor, and, lo, the little arm did come out as it should. When I switched the ignition off, it stayed out. Is that supposed to happen?
Anyway, I thought I'd do a bit of fine tuning, and screwed the little bolt that the rod pushes against out a little further (about one turn). The logic was that whatever should have been happening would now happen more so. I also made sure the battery was topped well up. The car started as it should, and restarted a couple of times during the evening. I hesitate to say it's ok now, as it could be an intermittent fault, but so far so good.
I have thought of replacing the coil as it looks original. Everything else should be in good condition now.
Wish me luck over the weekend! (There's no icon for crossed fingers.)
(By the way, do you still want those Monty doors?)
RobP

[mgdavid]

sounds to me like you have a tired battery, on the way out?

[RobertP]

Well you could be right at that. One of the things I have now done is to exchange the battery for a fully-charged one from my previous Maestro. I have also carefully set all the clearances on the stepper motor and the throttle to those specified in the Haynes book. Oh, and I also have swapped the coil from the other car, after giving it a good clean. She started ok about 5 times over the weekend, but I seem to have a rather fast tickover till the engine warms up, when it settles down. I can live with that. I'm very grateful to all those of you who have made suggestions; it's such a help not to have to struggle alone.
(It's odd, but whereas the Haynes manual seemed very unhelpful when I first looked at this problem, now that I know where all the bits are, it seems much better. Only one thing. On my other Maestro, also a 1.3, but 1993, there is a round black canister on the inside of the f/o/s wing, with the vacuum pipes from the top of the engine connected to it. It's about 9" high and 3 or 4" across. This is not in the manual, and not on Angina (1984 model). Does anyone know what it is?)

[G Force]

Hi, That will be the charcoal cannister for the fuel tank venting system, it was fitted to the very last petrol maestros that had catalitic converters.;)

[RobertP]

Well, I finally gave up. Having spent every Saturday on the car, checking and adjusting, I got the auto choke as good as it was going to get. In the very cold weather it worked ok, but then the weather changed, and I still couldn't trust it to start. I made the decision to try swapping the manual carburettor from the other Maestro, and, after a bit of a fiddle getting the choke cable through the bulkhead, I now have a car which starts when I want it to, not when it feels like it.
Many thanks to all who contributed to this thread.
Watch out for the next problem - a water pump which sometimes leaks, but mostly doesn't!

[ChrisM]

I now have a car which starts when I want it to, not when it feels like it.
Excellent! :D


Watch out for the next problem - a water pump which sometimes leaks, but mostly doesn't!That would be the leaky water pump I told you about... ;) I think it was actually the gasket which went, but don't quote me on that...

[RobertP]

I have bought a new water pump, complete with gasket, and also a tube of hermetite. Now all I need is to grow new hands with fingers 18" long, and several extra joints, so I can get at it!!!
It looks as if there is an access panel in the wing, which I assume I shall have to remove, as the water pump is almost invisible within the enormous r.h. engine mount.
The odd thing was that there has been no sign of a leak in the month I have been driving it, till that one eruption. It actually lost no more than a pint or so, and has gone dormant again. A bit like one of those volcanoes waiting to explode. I shall drive for now with a gallon of antifreeze mixture in the boot, and watch for puddles.
(Note to regulators - can we have a smilie with fingers crossed? It seems the most appropriate for my motoring career.):spanner: