Troubleshooting

I know very little about engines. When my car won't start, I haven't a clue what to do, where to look or what to try. It's depressing and you feel helpless

This is hopefully going to be a reference for things to try when your car is broken or won't start. It should provide a valuable starting place when you get that sinking feeling in your stomach and the search function is not helping.

It will no doubt become full of anecdotal advice, some of which may be contradictory or may not be relevant to your particular model. If you want to add to it, please keep to SOLUTIONS THAT HAVE WORKED rather than conjecture. That way it should cut down on arguments or deletions.

I'll start with a couple of my own soon but i'm not yet sure how to create subcategories. Feel free to edit, but consider it work in progress. If you know how to create subcategories under the main category of "Troubleshooting", please do it and save time. Thanks :-)

Car Won't Start

Absolutley nothing happens when key is turned (if you know solution, please edit this paragraph and supply an answer) Battery flat, I expect.

Clicking noise when ignition is turned - Some charge in the battery, but not enough. Charge battery or maybe jumpstart. Don't do what I did and try to jumpstart it from a 1.2l Diesel Corsa. It won't work.

Dash lights up but that's it did you hear the whirr of the fuel pump? if not, it could be one of the following reasons:

Fuel pump knackered - Apparently this is relatively uncommon but can happen. (can anyone who's had this happen edit this and explain how it was solved please). Fuel pump not working can also be caused by a wire that has rubbed sufficently that the plastic sheath has worn through and the wires have corroded and eventually snapped causing no power to the fuel pump.

Fuel pump fuse has blown (located in the boot on S1s) - Look in the passenger side of the boot and you'll find a black plastic circle. remove this and fiddle around inside until you can grab fuse. pliers are handy. 20A yellow fuse.

Problem with wiring - By the passenger seat (S1) is a small, metal, circular inspection cover. Remove this and someone handy with a multimeter can check if the fuel pump is drawing any current when ignition is turned. May help eliminate a problem, if not identify it.

Inertia switch has triggered - this is in the engine compartment (S1) and triggers in the case of an accident so that the fuel is cut off and reduces the risk of fire. it can be pressed to reset. It's like a big rubber button facing skywards, near the MFRU box.

MFRU (Multifunction Relay Unit) - this is a plastic box toward the rear of the engine compartment. It has a couple of big square plastic connectors and lots of wire going into it. I got water in mine after a particularly wet weekend. Had the symptoms described above. Drying the box helped restart the car but it went again due to corroded contacts on the connectors. Replacing the box (circa £40) solved the problem.

Starter Motor turns but the engine won't catch

You have put fuel in it, haven't you? - Oh how i laughed when both my brother and Mr AA man couldn't get his Vauxhall Nova to start. Tank was empty. Brother is a mechanic. Fools.

Has it rained heavily recently? Due to the engine cover having vents/holes in it (thereby making it unsuitable as a 'cover'), water can get to various places quite easily.

Is there a spark getting to the sparkplugs? - Someone confident in their electrical (and earthing) knowledge can check by taking off the main lead to the Distributor cap and 'sparking' it against an earthed part of the engine block. a mall spark should be seen. Haven't done this myself, so feel free to edit or even remove this suggestion if it is unsafe

Dry the Distributor Cap - This can be removed and dried quite easily in about 5-10 mins. Remember which lead attaches where.

Check the Distributor Rotor Arm - Despite my car producing a spark, it was misfiring on acceleration. Mr AA man diagnosed it as a small crack in the contacts of the Rotor Arm. Replaced for £7 quid, everything has worked fine since.

Check the Sparkplugs - Despite there being a cover over them, they can get water ingress. Remove the cover and pull the plastic tab. The rubber plug covers look like this: which one do you think was faulty? [[Image:[img]http://gallery.seloc.org/albums/userpics/28610/Photo-0047.jpg[/img]|thumb|caption text]].

See the Sparkplug Wiki page for replacement info. Can be bought from Halfrauds, nothing special. They even listed Lotus in the flipchart thing, which i was surprised about.

Is fuel getting to the engine? - Fuel pump problem?

Noises whilst Driving

Grinding Noises

Stones - could be stones caught between the brake disc and the brake pad. Do you have unexpected circular grooves ground out of the disc? Since the wheel is moving forwards, sometimes a quick reverse can dislodge the stone. Failing that, remove the wheel and take out the brake pad

Wheel Bearings - When mine went, I got a grinding, whirring noise that was related to car speed, not engine speed. It was there even when I depressed the clutch and the noise 'wound down' in pitch as the car coasted to a halt. Can also manifest itself when turning either left or right, indicated a problem side.

Dash has died (S2)

Car works, some lights come on but needles don't move - Could perhaps be caused by a bad earth. Disconnecting from the battery and reconnecting may 'reboot' the Stack Unit and sort out the problem (anecdotal advice)