Cutting out when hot - Advice on where to go next
Discussion
Hi All
Just hoping for a bit of advice on where you would go next to solve a cut out problem. A few weeks ago my (almost completely reliable in my 9 years ownership..) cut out suddenly just a few miles from home. It re-started after a while cooling down whilst I looked under bonnet for anything obviously. Anyway, I've since started up and noticed that it will cut out when hot. This isn't a splutter and cough, but a total on/off switch die. I have managed to work out that it's the ignition failing using an inline spark tester and have checked wiring and inside dizzy etc and can't see anything obvious. I've also had all wiring loom down in footwell and tried looking for loose wires, waggling, etc and nothing down there will cut it out. Tried the yellow connector in steering column and it seems OK.
So after some reading I think it's time to swap out coil and/or ignition amp, and for about £80 for the pair I'm happy do this. But the question is, is there anything else to reliably check before I do this? I have read about the Hall effect sensor on dizzy also causing these symptoms but think it'd rather try coil & amp first before taking that to bits. Maybe I'm wrong about that?
I followed this video which was pretty helpful but as the guy says, it's more for complete non-starters rather than cut out. https://www.youtube.com/watch?v=RWIH4WS6RAw&li... I think it'd be pretty tricky waiting for cut out and then diving to set this up before it cooled down to the point its all working again.
Thanks for any suggestions
Just hoping for a bit of advice on where you would go next to solve a cut out problem. A few weeks ago my (almost completely reliable in my 9 years ownership..) cut out suddenly just a few miles from home. It re-started after a while cooling down whilst I looked under bonnet for anything obviously. Anyway, I've since started up and noticed that it will cut out when hot. This isn't a splutter and cough, but a total on/off switch die. I have managed to work out that it's the ignition failing using an inline spark tester and have checked wiring and inside dizzy etc and can't see anything obvious. I've also had all wiring loom down in footwell and tried looking for loose wires, waggling, etc and nothing down there will cut it out. Tried the yellow connector in steering column and it seems OK.
So after some reading I think it's time to swap out coil and/or ignition amp, and for about £80 for the pair I'm happy do this. But the question is, is there anything else to reliably check before I do this? I have read about the Hall effect sensor on dizzy also causing these symptoms but think it'd rather try coil & amp first before taking that to bits. Maybe I'm wrong about that?
I followed this video which was pretty helpful but as the guy says, it's more for complete non-starters rather than cut out. https://www.youtube.com/watch?v=RWIH4WS6RAw&li... I think it'd be pretty tricky waiting for cut out and then diving to set this up before it cooled down to the point its all working again.
Thanks for any suggestions
Thanks, I've already ordered a coil though from TVR Parts so can't switch now.
Take it you had exact same symptoms then? I really hope it's the coil (or amp if not). Apart from failing loom wiring I can't see there's much left in the ignition system to cause total loss of spark seemingly caused by heat or perhaps duration of use.
Take it you had exact same symptoms then? I really hope it's the coil (or amp if not). Apart from failing loom wiring I can't see there's much left in the ignition system to cause total loss of spark seemingly caused by heat or perhaps duration of use.
Hi Stopit
That's some good advice right there. Well at this stage I've already ordered the new coil before your post so I'll just fit that anyway. If problems persist I'll definitely rig up that test. If the bulb does go out does that indicate a bad earth or bad +ve feed or either/both?
That's some good advice right there. Well at this stage I've already ordered the new coil before your post so I'll just fit that anyway. If problems persist I'll definitely rig up that test. If the bulb does go out does that indicate a bad earth or bad +ve feed or either/both?
Hi
I fitted my new coil last weekend and still cut out. Boo.
So I am about to try the method described by Mr Stopit above but since my car cuts out just sitting on drive idling after 10 mins or so and then won't start for about 20mins or so, do I need to connect a bulb? This is just for a visual whilst driving I guess, but if I can test the +ve coil supply right away when it cuts out, could I just stick a multimeter on it and turn the car over so the dizzy is spinning and observe the supply that way?
I fitted my new coil last weekend and still cut out. Boo.
So I am about to try the method described by Mr Stopit above but since my car cuts out just sitting on drive idling after 10 mins or so and then won't start for about 20mins or so, do I need to connect a bulb? This is just for a visual whilst driving I guess, but if I can test the +ve coil supply right away when it cuts out, could I just stick a multimeter on it and turn the car over so the dizzy is spinning and observe the supply that way?
I'm really not sure about the earth situation there. I can't trace the wiring so well as a lot of it is combined with other wiring in heat shrink. Any ideas where I'd start looking for the earth for this amplifier module?
I did try this time again with my spark detector installed on the king lead and when it cut out after 10mins there was no spark there so I think I can rule out the dizzy itself. When there was no spark, I checked the power supply on the +ve and -ve coil connections and both were 12.8V dropping down to about 9V during the time when it was turning over which I guess is just down to the load being pulled during turnover on starter motor etc?
So no spark from coil but power supply seemingly there to both +ve and -ve so does that point to amplifier module now? Either the module itself or the earth connection to it?
I did try this time again with my spark detector installed on the king lead and when it cut out after 10mins there was no spark there so I think I can rule out the dizzy itself. When there was no spark, I checked the power supply on the +ve and -ve coil connections and both were 12.8V dropping down to about 9V during the time when it was turning over which I guess is just down to the load being pulled during turnover on starter motor etc?
So no spark from coil but power supply seemingly there to both +ve and -ve so does that point to amplifier module now? Either the module itself or the earth connection to it?
OK I'm going to do the measurements as suggested.
Only thing I'm confused about though is when the car is functioning properly when cold, if I measure the coil with -ve disconnected and linked back to battery or good earth, this could show that all is well in terms of the supply. Which it probably would. So I would need to wait until the car has stopped running when warm (when something is breaking down electrically) and then rig up this arrangement?
Only thing I'm confused about though is when the car is functioning properly when cold, if I measure the coil with -ve disconnected and linked back to battery or good earth, this could show that all is well in terms of the supply. Which it probably would. So I would need to wait until the car has stopped running when warm (when something is breaking down electrically) and then rig up this arrangement?
A little update here. So I've tested everything as advised as Stopit recommended and it came back in normal range in those conditions. I also have been reading this section from the Range Rover Classic manual.
I have followed these steps too and apart from one check which I can't understand how it could be correct in the manual, all checks lead to amplifier module. I bought new and replaced and I ran it for half hour without cutting out. Previously it cut after 5-10mins. I'm going to take it for a drive to test it out more but that's where I'm up to now.![](https://thumbsnap.com/t/FxHh6H6L.jpg[/img]</a> <a href="https://thumbsnap.com/Qz4c3E5S" Target="_blank" rel="nofollow">[img]https://thumbsnap.com/sc/Qz4c3E5S.jpg)
I have followed these steps too and apart from one check which I can't understand how it could be correct in the manual, all checks lead to amplifier module. I bought new and replaced and I ran it for half hour without cutting out. Previously it cut after 5-10mins. I'm going to take it for a drive to test it out more but that's where I'm up to now.
Yep that has to be what's happening on that test.
One more thing, I bought my amp module from Race tech and the guy said I should buy the 3 pin one even though mines a 2 pin originally cos he's had so many 2 pin versions fail due to poor quality. The 3 pin ones they sell are decent apparently.
I had to cut the 2wires and create new connector plug. You just don't use the centre pin. I think that must be an earth for when the module is mounted remote from dizzy as it earths through the mounting plate screw on the dizzy in my case
One more thing, I bought my amp module from Race tech and the guy said I should buy the 3 pin one even though mines a 2 pin originally cos he's had so many 2 pin versions fail due to poor quality. The 3 pin ones they sell are decent apparently.
I had to cut the 2wires and create new connector plug. You just don't use the centre pin. I think that must be an earth for when the module is mounted remote from dizzy as it earths through the mounting plate screw on the dizzy in my case
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