2001 Megane sometimes not starting

[Deleted User]

My 2001 petrol Megane has recently developed a fault where it sometimes struggles to start first, second, or even third time. It has always eventually started though. It is completely random when it does it, car could be parked up and not used for 2 days and it will start fine, but then it will fail to start first time a few hours later.

Don't think it is the battery as it is trying to turn over, not just nothing like what you get with a flat battery? Possible starter motor?

Marktheshark

Relays !
Fuel injection solenoid relay sticking.
made many a garage a small fortune for a £3 part.
Google it.

[Deleted User]

Thanks, wonder what the going rate is to have this sorted at back street inde garage.

forgotmyname

If its cranking over at normal speed it wont be the battery or starter.

Coil pack or is it single coils on each cylinder on yours? Either way they are a weak item and fail quite often.

Fuel consumption increased? Slight judder or misfire or doesnt feel as nippy as it used to?

mcjordi

any dash lights on?

quite possible crank posistion sensor gone/going..
check for spark take out coil 4 (irc the french did it backwards so coil 4 is coil 1 ) and rest it with plug on some bare metal and check for spark as some one turns the car

[Deleted User]

forgotmyname wrote: »

If its cranking over at normal speed it wont be the battery or starter.

Coil pack or is it single coils on each cylinder on yours? Either way they are a weak item and fail quite often.

Fuel consumption increased? Slight judder or misfire or doesnt feel as nippy as it used to?

Cranks over at normal speed so that rules out the starter motor then.

There is no judder or misfire, car still runs smoothly and nippy when engine is running. I know all about judders and misfires from my old 206.

mcjordi wrote: »

any dash lights on?

quite possible crank posistion sensor gone/going..
check for spark take out coil 4 (irc the french did it backwards so coil 4 is coil 1 ) and rest it with plug on some bare metal and check for spark as some one turns the car

No lights are on on the dash. I'll check coil 4 but it doesn't do it all the time. E.g it has started first time twice already this morning.

Marktheshark

Google the relays and swap them over, they have 4 or more the same, if the problem solves itself, buy a new relay.
"A back street garage" will rub their hands if its the relay and start swapping parts tooth sucking and a huge bill usually, was this that and the other mate.

Strider590

Marktheshark wrote: »

Google the relays and swap them over, they have 4 or more the same, if the problem solves itself, buy a new relay.
"A back street garage" will rub their hands if its the relay and start swapping parts tooth sucking and a huge bill usually, was this that and the other mate.

I don't know why you point the finger at "back street garage"s, dealerships and "rapidfit" centres are the biggest culprits for ripping people off.

arcon5

I don't know why garages in general are taking a beating here... yes, the part may be £3, doesn't though take away from the fact they've probably checked a dozen things, read live data and codes and tested components before they have pinpointed the exact fault and rectified it.

Just be please they've spent an hour and cost you £40 to identify the fault costing you just another £3 to put right. Rather than spent an hour and found a fault costing you £300 to fix.
Damned if they do, damned if they don't.

It's all about what they bring to that hour. If you don't like paying £40+£3 for labour+part then develop the knowledge, buy the tools and diagnose the fault yourself.

[Deleted User]

arcon5 wrote: »

I don't know why garages in general are taking a beating here... yes, the part may be £3, doesn't though take away from the fact they've probably checked a dozen things, read live data and codes and tested components before they have pinpointed the exact fault and rectified it.

Just be please they've spent an hour and cost you £40 to identify the fault costing you just another £3 to put right. Rather than spent an hour and found a fault costing you £300 to fix.
Damned if they do, damned if they don't.

It's all about what they bring to that hour. If you don't like paying £40+£3 for labour+part then develop the knowledge, buy the tools and diagnose the fault yourself.

I never said I didn't want to pay a garage. But I have paid £40 in the past for a garage to fail to diagnose a problem on my old 206 in the past though. And another £12 to another garage for the same result. Don't really want a repeat of that.

rockin_plumber

I had this exact same problem on my 2001 Renault Megane...


Start fine then wouldn't, turned over fine just not firing.


Turned out to be the TDC Sensor.