Hot Start Issue
Discussion
Hi,
Don't know if anyone here can point me in the right direction please? I did have a quick search but nothing turned up.
My 2000 NB 1.8 has developed an annoying problem (typically, 1 month after I bought it)
Normal short journeys are fine, but if I go any distance it will refuse to start for about 30 minutes after I stop. It's ok for the first 5 minutes or so after I stop, so I suspect there is some sort of heat-soak issue going on. Problem is worse in hot weather and the car is black, so that doesn't help either. I've just been to Cornwall and the only way to manage it when I stopped was to open the bonnet for 10 minutes to let some of the heat radiate out. Obviously, this is sub-optimal. Other than that, it seems fine. No hesitation, mis-fires etc, even when it does start after cranking for 30 seconds!
So I suspect this may be either;
1) Temp sensor somewhere
2) Crank position sensor
3) Coil packs
4) Anything else?
Does anybody have any advice on how to deduce failure of the above? I don't really want to go replacing parts that might not work - cost, time etc.
Don't know if anyone here can point me in the right direction please? I did have a quick search but nothing turned up.
My 2000 NB 1.8 has developed an annoying problem (typically, 1 month after I bought it)
Normal short journeys are fine, but if I go any distance it will refuse to start for about 30 minutes after I stop. It's ok for the first 5 minutes or so after I stop, so I suspect there is some sort of heat-soak issue going on. Problem is worse in hot weather and the car is black, so that doesn't help either. I've just been to Cornwall and the only way to manage it when I stopped was to open the bonnet for 10 minutes to let some of the heat radiate out. Obviously, this is sub-optimal. Other than that, it seems fine. No hesitation, mis-fires etc, even when it does start after cranking for 30 seconds!
So I suspect this may be either;
1) Temp sensor somewhere
2) Crank position sensor
3) Coil packs
4) Anything else?
Does anybody have any advice on how to deduce failure of the above? I don't really want to go replacing parts that might not work - cost, time etc.
Not sure where to find the values, but I'd be checking the resistance of the coolant temperature sensor. If it's knackered, it could be telling the ECU that the engine is cold and not giving it the right fuel mixture/ignition timing to start the engine.
Or it could be the residual heat when parked causing the ignition coil to fail.
Or it could be the residual heat when parked causing the ignition coil to fail.
Unlikely to be the coolant thermister at fault.
It's relatively common for the cam sensor to fail on these year cars, typically when they've heatsoaked, which sounds like conditions your car won't start in.
It's a relatively expensive genuine part, but available much cheaper as a pattern part. It's only a 2 minute job to change too.
http://www.mx5parts.co.uk/camshaft-position-sensor...
EDIT: just to add the MK2 & MK2.5 sensors are identical, in case you thought I linked the wrong part.
It's relatively common for the cam sensor to fail on these year cars, typically when they've heatsoaked, which sounds like conditions your car won't start in.
It's a relatively expensive genuine part, but available much cheaper as a pattern part. It's only a 2 minute job to change too.
http://www.mx5parts.co.uk/camshaft-position-sensor...
EDIT: just to add the MK2 & MK2.5 sensors are identical, in case you thought I linked the wrong part.
Edited by Richyvrlimited on Friday 10th July 08:46
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