What is this Thing?

Thargor

Sorry i dont have a pic but under the battery on our Mondeo theres this black cylinder secured by 2 bolts with wires coming out of it and its started making an incredibly loud and annoying screeching noise when the engine is on whether the car is moving or not, anyone know what it is?

Plug

What year? Petrol or diesel? What size engine?

Thargor

98 Diesel, not sure about engine size, I dont drive it, the cylinder is directly under the battery, its about the size of a can of coke with 2 or 3 wires coming out of it, the wires go into the engine somewhere, cant see where, any clues? Sorry for the crappy description, cars are not my thing.

Fozzie Bear

A bit obvious maybe.... is it the car alarm?

Thargor

No no no, Im not that bad, its a mechanical screeching noise like something rubber rotating and rubbing off some metal as it goes round, and its not the brakes because it does it while the car isnt moving. Its a fast, high pitched yeep-yeep-yeep-yeep-yeep-yeep kind of noise, totally head-wrecking.

Thargor

Is there any site that will give you the engine diagram so I can find out the name of the cylinder?

Plug

Thargor wrote: »

98 Diesel

I haven't a clue then sir. I never really worked on the older Mondeo.

peasant

No idea about Mondeos ...but it could potentially be the relay for the pre-glow pluggery.

These draw a pretty high current and are switched with a relay ...stuck relays tend to screech/squeal.

just a guess

Thargor

That sounds like it judging by a quick Google alright, thanks peasant. My father has has another old mondeo that he keeps for parts, do you think that would be easy to switch or is it a job for a mechanic? Thanks for the help anyway everybody.

peasant

If it is indeed a relay it should be possible to just swap them out.

Make sure to disconnect the battery before going near it


EDIT:
Can of coke sounds a bit big for a realy ...there's possibly some other components in there too.

Anan1

Would it be the starter motor failing to disengage?

Plug

Anan1 wrote: »

Would it be the starter motor failing to disengage?

Im not playing a with a full deck of cards today, spot on sir:D

Anan1

Plug wrote: »

Im not playing a with a full deck of cards today, spot on sir:D

* bows graciously in acknowledgement *

peasant

Starter motor under the battery?

Plug

peasant wrote: »

Starter motor under the battery?

It would be down that general area.
OP is the back cylinder bolted on to the engine/gearbox.

Thargor

I cant check now but I will, thanks Plug.