Might be a red herring? Mine dosent move either during starting. When you think about it, a starter is only going to spin the engine at a few rpms, probably less than a 100, whereas the first main division on most Rev counters is 1000 rpm, so it is hardly surprising the rpm needle dosent move under cranking:spanner:

 

It could be nothing, but mine jumps when you crank the engine - could be a sign of a faulty ecu?

 

I'm having a problem starting my car, I have noticed that the rev counter doesn't move when the starter moter is turning the engine, is this normal? I thought I read something about this on this forum somewhere but I can't find it.

Cheers

it wont; the alternator supplies the source pulse for the rev counter, and it is electrically isolated during starting to prevent it (the alternator) getting knackered.

on some diesels witha rev counter (particularly older ones from certain brands) the rev counter only starts working when the battery light goes out. the battery light is an indicator that the alternator is not charging the battery, and the key thing with it is, that some cars dont extinguish the battery loight (i.e. switch the alternator to active charging mode) until the engine is revved slightly.. so the rev counter would lie on 0 rpm with the engine ticking over, until the engine was revved slightly

 

by the way.. im not sure what you were asking.. if the behaviour of the rev counter is normal, or if it is related to the starting of the car. you might find its something as simple as a weak battery; the colder weather is now hitting us, and batteries are the first thing to give up on a car in weather like this

 

It could be nothing, but mine jumps when you crank the engine - could be a sign of a faulty ecu?

more likely problematic isolation of the alternator.. but it does depend ont he specific car. some cars take their rev counter feed from the current induced in a wire wrapped around an ht lead; the ht current causes pulses in a wire that the rev counter uses to measure the rpm.. one pulse = 1 rev if the sensor is on a plug lead, or 4 pulses = 1 rpm if it is on the coil feed (on a 4 cylinder engine). plug lead is more common.

because this kind of rev counter is electrically isolated from everything else, it does not need protection, and can start working immediately when there are sparks travelling down the ht lead. because sparks are needed to make your engine go, it starts working as soon as you use the starter, and is of no concern. the only time i would be concerned over a rev counter moving while cranking an engine, would be if i knew the rev xcounter was driven by the alternator

 

the only time i would be concerned over a rev counter moving while cranking an engine, would be if i knew the rev xcounter was driven by the alternator

I'll have a bit of a ferret and see if I can discover where its taking its feed from then.

 

We need to know whether the car is petrol or diesel really.....

 

... that some cars dont extinguish the battery loight (i.e. switch the alternator to active charging mode) until the engine is revved slightly.. so the rev counter would lie on 0 rpm with the engine ticking over, until the engine was revved slightly

Yup, my 418 Does that from time to time.

 

We need to know whether the car is petrol or diesel really.....

Mine's 'M' reg 214 SEi. I'm sure the rev counter would flicker, but my non-starting car doesn't.

Cheers

 

Coil is on the way out as this supplies the clocks with a signal
HTH
Steve

 

Does this car have a FIP (fuel injection pump)?

If it does, I reckon (from my own experience) it is bound to be a bad earth connection, leading to the EMU (big relay box), which leads to the fuel cut off solenoid on the FIP, its more likely a bad earth, but PLEASE PLEASE check the fuse in the engine bay! Make sure you check that!

Get back to me on that one!

 

Does this car have a FIP (fuel injection pump)?

If it does, I reckon (from my own experience) it is bound to be a bad earth connection, leading to the EMU (big relay box), which leads to the fuel cut off solenoid on the FIP, its more likely a bad earth, but PLEASE PLEASE check the fuse in the engine bay! Make sure you check that!

Get back to me on that one!

Thanks for your advice I will look at this tomorrow.

Cheers