As you probably remember I replaced my alternator a while back, in the end I used a Denso unit, out of a Doblo, with matching part number to my one.

Now recently it's not behaving as it should and I'm suspecting it's this alternator, the car judders and shakes, the dash lights and headlights flicker ever so slightly and since yesterday the oil level goes up and down

The stereo is dead too but that might be coincidental as I've not had much luck with audio equipment in this car ever... :bang: or cars for that matter

Sounds like a bad earth

boilermansab said:

Sounds like a bad earth

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does that explain the car shaking though?

No..but bad earth can cause all sorts of problems...
Car shaking worse case could be dmf faliure..but won't go down that road!

hastingsmum said:

does that explain the car shaking though?

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Could do, if the injector circuit is being affected.

Didn't you have an issue with the key barrel a while back, or was that someone else?

Perhaps a cable come loose on alternator? Check battery terminals are tight? Or may be the earth cable to the gearbox is corroded?

BikeDoc said:

Could do, if the injector circuit is being affected.

Didn't you have an issue with the key barrel a while back, or was that someone else?

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Yes I did but that's not an issue atm

widemouthfrog said:

Perhaps a cable come loose on alternator? Check battery terminals are tight? Or may be the earth cable to the gearbox is corroded?

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Battery terminals are tight, though the positive one is bodged slightly it should still work.

widemouthfrog said:

Perhaps a cable come loose on alternator? Check battery terminals are tight? Or may be the earth cable to the gearbox is corroded?

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I'm thinking it must be something that doesn't have a back-up, so to speak.
E.g., if the Alternator (or a connection) was duff, the Battery would still supply power.
And vice-versa, it must be something that affects both Alternator and Battery, or something unconnected to them, but that affects the injector circuit, such as the 'ignition' switch.

hastingsmum said:

Yes I did, but that's not an issue atm

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Are you sure?
You may have cured the original fault, but it could still be playing up in another way, say with a dodgy connection, affecting the injector's power supply . . . maybe.

BikeDoc said:

I'm thinking it must be something that doesn't have a back-up, so to speak.
E.g., if the Alternator (or a connection) was duff, the Battery would still supply power.
And vice-versa, it must be something that affects both Alternator and Battery, or something unconnected to them, but that affects the injector circuit, such as the 'ignition' switch.




Are you sure?
You may have cured the original fault, but it could still be playing up in another way, say with a dodgy connection, affecting the injector's power supply . . . maybe.

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Well yes I'm pretty sure, with a new key cut it starts like it used to, so ignition barrell is prbably worn yes but the key was more worn.

When I had just fitted the alternator one of the leads at the back of it was slightly loose and then the lights flickered a bit too but I got the alternator faulty light on as well, which I don't have right now (fingers crossed lol), but I will have a thorough look at them all tomorrow in the rain

and I realise my reply is just ignoring everything you just said... sorry, so where do I look then if it's not the alternator or battery?

The earth cable from the battery to the gearbox can fail, or just become a bad connection onto the gearbox. So check it is secure and not broken, especially where the cable fits into the connector tag. The cable usually then carries on to the car body, so using one cable rather than two. So check this too.

Then check any earths that connect to the engine. Some of the smaller petrol engines have a connection to the cam cover that is known to corrode. There may be something similar on yours. See if the manual can give any clue to ECU earth points/locations.

PS: Love the thread title. Had to look, just to see if it was the car or the owner misbehaving.

hastingsmum said:

. . . so ignition barrel is probably worn . . .

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That's what I'm getting at.
In the base of the unit there are several fixed Copper strips that the electrical circuits are connected to.
When the key is turned, it rotates another set of strips that make/break the electrical circuits, if any of these are worn, dirty, corroded etc, then you can get problems.
This is an example of the fixed contacts, not a Multi, but it will be similar . . .

Another example. The upper part is the fixed section, with the connector spades, the lower part is turned by the key, the Copper segments make/break the electrical circuits through those connectors . . .


Not an easy thing to check however, as it's just about impossible to strip down without destroying the unit.
Did you try the switch cleaner spray I suggested before (in the original thread about it)?

portland_bill said:

PS: Love the thread title. Had to look, just to see if it was the car or the owner misbehaving.

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BikeDoc said:

Did you try the switch cleaner spray I suggested before (in the original thread about it)?

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Don't think I saw that no, just everyone saying I needed an expensive autolocksmith ... will check back

Thank you for all the advise, fingers crossed it's not as complicated as it sounds.

There are dozens of switch cleaner sprays available, if you have a Halfrauds or Maplins near you, try them.
If not, search ebay for 'Switch Cleaner Spray' or 'Electrical Contact Cleaner'.
You want one that's labelled as 'residue free'.

BikeDoc said:

There are dozens of switch cleaner sprays available, if you have a Halfrauds or Maplins near you, try them.
If not, search ebay for 'Switch Cleaner Spray' or 'Electrical Contact Cleaner'.
You want one that's labelled as 'residue free'.

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Now that you mention it I have electrical contact cleaner already

I started the car this evening to see if the problem had miraculously disappeared.... but the only thing I noticed was that the flickering only started when I revved the engine.

The dashlights got stronger when I took my foot off the clutch and even stronger when i pressed the accelerator but flickering at the same time.

This might be all perfectly normal or as expected but just thought I should mention it before I start looking for solutions to this issue.

Seems very likely to be a dicky contact. As the engine vibrates, the contact is moving, so the earth wire to the engine seems the first place to look. If it is covered, it might have become brittle inside, and is making/breaking as the engine moves. Also need to check the power cable from battery to alternator to ensure tight. If this is fixed to the alternator with a nut, ensure the post in the alternator is also tight.

Stick the meter across the battery and check the voltage output of the alternator. It might be a duff one. If its output is erratic, check the brushes are free to move before condemning it. If it has been stored for a while they may just be a bit sticky.