Car trouble, won't start, goes tick-tick-tick-tick instead.

tick-tick is *usually* the starter solonoid failing to engage.

On old cars, the solonoid operated relay contacts and the starter was engaged to the flywheel with a drive cog on a splined shaft that threw itself in when the motor ran.

On "modern" (70's onwards probably), the solonoid actually engages the starter cog and when that's happened, the contacts make.

Failure to do this can be stickiness on the shaft, something worn or lost grease.

Most people at this point swap the starter for a recon which is around

If it's better after a run, it may be that heat has softened what little lubrication is left - or you got luckier the next time with how the flywheel teeth ended up more aligned with the starter cog.

In message , Justin C writes

Could be a duff battery, or battery connection, when you use the electric start and the solenoid connects the supply to the starter motor the volts drop enough that the solenoid releases, then as there is less current being drawn it pulls back in, releases again etc. Does it sound like a sharp, rapid mechanical tick? If you have your lights on when you try to start it do they drop out too? (No I don't mean laterally fall out)

Tim - 5 times a second is a hell of a fast for a sticky starter solenoid, they really do have too much mass to go at that speed; my experience is a couple of times per second at the very most. If it really is as fast as the OP says, then that is a small relay chatter.

At that point I will bail out as I haven't a clue what it could be. I would make the suggestion that the OP tries to identify if the chatter is in the engine bay or the electrical panel.

rob

Take it to a garage.

Or a dodgy earth strap (to battery or chassis engine) - anything which won't carry the heavy current needed to turn the engine over.

My Ford Cmax diesel will do this when the weather is very cold and the car has not been used for days. The engine will turn over reasonably but it seems the battery voltage is low enough for certain relays to drop out on the compression strokes and thing wont start. When it does fire it comes up with a power steering fault message but there is no fault and it will behave for the rest of the day thereafter. It has got a smart charge system on it (waste of time!) and silver calcium battery which really needs a good long run to get the battery to recover from lots short journeys. It is 7.5 years old and possibly needs a new battery but I find that regular charging through the cold weather avoids the problem.

Bob

I guess. I had it once and it was quite rapid and was a failing starter unit. But I didn't actually try to time it :-0

This is a good idea.

Another thought - if it does it again, engaging gear and moving the car a few inches by hand can allow the cog to engage on the next attempt so if that proves true, it points more to the starter - something for the OP to try.

Sounds like a near flat battery or poor connection to it. Have you had the battery and charge rate checked?

As others have said, it's the starter solenoid going into spasm due to insufficient urge from the battery.

My wife's Puma has done this several times when it hasn't been used for a bit in cold weather. Connecting a battery charger and giving the battery a boost for a couple of hours usually cures it.

This is the voltage dropping very low causing the relays both inside & outside the car to oscillate.

Classic sign of a bad negative connection to the battery terminal and often the gearbox, together with a failing battery which can be aggravated by the former. You may find there is one cable from the negative terminal to the body of the car nearby, but this continues on to a negative terminal on the engine or gearbox itself. This is to ensure a low impedance return for the starter - as well as most engine sensors which have their grounds typically attached to a common grounding plate. This grounding plate is often removed during clutch or other maintenance and the connection for both high current ground AND plate retention is via the same nut passing over a cable stud. Once this works loose you get a poor ground connection at the starter

- the physical movement of the gearbox/engine will cause a good connection then bad connection alternately. The engine runs better in wet than dry weather. Starting is intermittent "two goes", and the starter acts as though the battery is weak (which it may be, but this compounds the problem).

Car battery voltage may well be high enough to operate everything as normal, but the starter draws 90-150A+ which causes the voltage to drop as soon as the starter solenoid engages - so causing the battery voltage to drop out releasing the relays and solenoid.

If the solenoid is going bad you usually get a click... (nothing) which is heard only once with each turn of the key. That is quite different. The clack-clack-clack-clack is classic battery voltage dropping out - usually a bad battery but really check BOTH ends of the negative cable re battery, bodywork AND engine (starter) ground. Warning, the starter has an always "hot" positive, connecting that to ground will result in a lot of sparks and worse so remove everything metallic re watch and ensure goggles are worn anyway when working with a suspect dead battery. They can freeze at about -18oC and they can explode throwing acid around, particularly if abused.

Bosch do a good range of known good batteries, Exide and similar "Kwik Fit" batteries are a bit weak (2yrs if your car has a high current drain). If the battery regularly fails at about 18-24 months check the battery discharge. Some alarms as they age can cause higher draw some time AFTER the car is left, they can trigger the power locks or leak into the power lock circuit. This will drain the battery (sometimes obvious re door locks keep operating, other times a silent battery killer). Likewise some interior light switches (boot/trunk, bonnet/ hood, door, glovebox) can get stuck on and cause a drain.

The engine negative ground on FWD is often in a difficult to access place, such as low down on the gearbox, and the bolt can get cross- threaded so it appears tight but in fact all the grounds are intermittently floating. Well worth checking after a clutch change, it will produce rough running and random error codes, poor battery life and is rarely checked.

Perhaps they're inside next doors car?

The battery is knackered.

MBQ

Heh-heh...

- Relays Inside the passenger compartment

- Relays outside the passenger compartment, under the bonnet (fuel, ECU & main relay, solenoid relays).

Oh indeed, but please check the grounds on Battery + Car-Body + Engine.

The circa 16mm^2 Engine ground often requires removal of fresh air duct, air filter, air mass/volume meter, various ducts & hoses, even fuel filter & other metalwork hence it gets missed. Engine & exhaust mounts are an insulator, the small grounds across the mounts are trivial as far as Starter Ground and Alternator Ground are concerned.

Any aftermarket negative battery terminal should be treated with suspicion - anything non-factory needs to be a good stud with ratchet crimped terminal. The Duratec V6 has a reduction drive starter of about 1.4kW and is quite heavy on the battery during cold starts.

Stuffed battery, check those grounds otherwise the replacement isn't going to last long either.

Not just the earths, but the +ve connections (or -ve if it's a very old car!).

My previous Honda 2.2 diseasel made a fast chattering noise when it was time for a new battery ...

high resistnce battery or battery lead or flat battery.

try tightening battery contacts and connections to the starter motor - the BIG cable from the battery.

If that don't work replace the battery.

Following on with the general concensus that the chattering is probably caused by insufficient power from the electrical system, either a bad earth or a bad battery (or both). You could try using a jump lead as an additional connection from the earth terminal of the battery to bare metal on the engine somewhere. If this helps, suspect the earth strap between engine and chassis.

It could still be the starter motor - I know on my Volvo the starter still engages with a very low battery - just refuses to turn the engine.

Time to look over all the charge and starter circuit connections and leads. Corrosion of the wires may be internal and loaded testing looking at volt-drops or direct close examination (cutting back a little insulation looking for oxidation) is the only way of checking. As a quick treatment, clean any grease from the battery terminal clamps and additional tagged on wires. I believe this was causing the majority of the problem I had recently. Also the chassis connecting wire was internally corroded. If you do make a replacement to a battery wire, use a tinned and sleeved braided wire for reliability.

Probably dirty/corroded battery connections.

Clean the battery posts and the battery lead connectors on them, and then the other ends of the battery leads and whatever they are connected to.