Engine cutting out at 70/75 degrees.....
Discussion
Have posted before and tried a few things but the problem remains!
Basically I start the engine, let it run and it simply dies at around 70 degrees-ish. It doesnt matter wether the car is stationary (which I do so it doesnt cut out when moving) and as soon as this temp is reached, after i restart, it runs fine.......am I missing something simple?
Would appreciate your comments please, chaps!!!
Dave.
Basically I start the engine, let it run and it simply dies at around 70 degrees-ish. It doesnt matter wether the car is stationary (which I do so it doesnt cut out when moving) and as soon as this temp is reached, after i restart, it runs fine.......am I missing something simple?
Would appreciate your comments please, chaps!!!
Dave.
I had a similar issue on my Wedge.
Changed the coil, still did it.
Changed the ignition amp, still did it.
In the end, I bypassed the LT ignition circuit to the coil and it ran OK.
Finally traced the fault back to a dodgy fuse holder. Snipped the wires and transferred them to new single fuse holder. This fixed the problem.
The next time yours cuts out try a couple of things.
A bag of frozen peas wrapped around the coil, and bypass the ignition circuit.
Changed the coil, still did it.
Changed the ignition amp, still did it.
In the end, I bypassed the LT ignition circuit to the coil and it ran OK.
Finally traced the fault back to a dodgy fuse holder. Snipped the wires and transferred them to new single fuse holder. This fixed the problem.
The next time yours cuts out try a couple of things.
A bag of frozen peas wrapped around the coil, and bypass the ignition circuit.
You mention that once 75c has been reached and the fault occurs on restart the car runs normally. Components like coils and ignition amps generally once hot and faulty remain faulty until they cool. So very unlikely to be the problem. Could the problem be time related? The stepper motor in the bypass air valve operates once the engine is up to temperature to alter the mixture and reduce idling speed, perhaps the problem lies there? The stepper motors are notoriously unreliable and do need cleaning, as they tend to stick. Suggest this is given a good clean. Lots of info on here and elsewhere as a guide.
Watch exactly what happens on the rev counter as it dies...
Sudden cut is probably lost signal from coil to tacho + ecu, winding down ign is OK (but could still be wire from coil to ecu or those diodes near the AFM pipe)...
.. with no tach signal the ecu shuts down as it thinks the engine has stopped (even though it may still be spinning...).
Sudden cut is probably lost signal from coil to tacho + ecu, winding down ign is OK (but could still be wire from coil to ecu or those diodes near the AFM pipe)...
.. with no tach signal the ecu shuts down as it thinks the engine has stopped (even though it may still be spinning...).
Some top replies, fellas and thanks. Gut feeling now is AFM.......think it has seen some better days (bit like myself at moment, arent domestic issues just great?) however, will check all hopefully on Tuesday and obviously let you know !
Apologies for no reply sooner, like I said, domestic issues (read women!) and being away in Scotland (work).
Thanks all...
Dave
Apologies for no reply sooner, like I said, domestic issues (read women!) and being away in Scotland (work).
Thanks all...
Dave
blitzracing said:
As the man says about the AFM, they get pretty hot near the manifold, and if they become faulty the can make the car run rich, and it will then die at idle.
Mmmm, only problem is here is that, as it did on a run on Tuesday, it cuts out once the temp gets below 78c whilst doing 70 on the M6!!!! It did restart but you see my worry!!!!Cleaned up some connectors only on Tues, didnt really have an awful lot of time so still need to look at things......
Dave.
Don't forget the live feed to the coil is one of three things that goes through the immobiliser.
1) Live to coil
2) Live to starter solenoid
3) Live to fuel pump
The relays inside the immobiliser were wired back to front by TVR and consequently their contacts become pitted over time.
It's a common problem, usually its the relay that controls the feed to the starter solenoid that goes first as it carries more amps, but it could easily be the one that sends the live to coil in your case.
I would be tempted to run a new temporary live feed to the coil thus bypassing the immobiliser completely.
It's a 10 minute job to do, all you need is a solid 12v at the coil to energise it.
Once done, drive it and see if the problem disappears, if it does you can do a permanent job of bypassing the immobiliser or better still get Carl Baker to fit a new one.
Worth a go.
1) Live to coil
2) Live to starter solenoid
3) Live to fuel pump
The relays inside the immobiliser were wired back to front by TVR and consequently their contacts become pitted over time.
It's a common problem, usually its the relay that controls the feed to the starter solenoid that goes first as it carries more amps, but it could easily be the one that sends the live to coil in your case.
I would be tempted to run a new temporary live feed to the coil thus bypassing the immobiliser completely.
It's a 10 minute job to do, all you need is a solid 12v at the coil to energise it.
Once done, drive it and see if the problem disappears, if it does you can do a permanent job of bypassing the immobiliser or better still get Carl Baker to fit a new one.
Worth a go.
Edited by Chimpafrolic on Thursday 6th October 20:11
I know the ECU has been mentioned, but below 70 degrees the ECU is running a cold start enrichment mode and once 70 degrees is reached the ECU adapts to run at normal temps. When cruising and the temp drops back to 70 degrees the ECU can be fooled and it retuns to 'cold' mode. This adaption by the ECU could be causing the engine to cut out around 70 degrees. Normally the engine would just run rich and use more than normal fuel levels.
Chimpafrolic said:
........
The relays inside the immobiliser were wired back to front by TVR and consequently their contacts become pitted over time.
How can the relays be wired back to front?The relays inside the immobiliser were wired back to front by TVR and consequently their contacts become pitted over time.
Each relay in the immobiliser presents a set of normally open contacts that close when the immobiliser is deactivated.
relay contacts are not polarity sensitive so not sure what you mean here? Perhaps you can explain?
It is well known that the starter relay contacts in the immobiliser fail due to excess current passing through them are there other reasons?
Edited by Loubaruch on Thursday 6th October 22:13
Loubaruch said:
Chimpafrolic said:
........
The relays inside the immobiliser were wired back to front by TVR and consequently their contacts become pitted over time.
How can the relays be wired back to front?The relays inside the immobiliser were wired back to front by TVR and consequently their contacts become pitted over time.
Each relay in the immobiliser presents a set of normally open contacts that close when the immobiliser is deactivated.
relay contacts are not polarity sensitive so not sure what you mean here? Perhaps you can explain?
It is well known that the starter relay contacts in the immobiliser fail due to excess current passing through them are there other reasons?
Edited by Loubaruch on Thursday 6th October 22:13
After all you are just energising a coil.
But I am not referring to the low current control circuit, it's all about the flow of electrons through the contact tips on the high current side of the relay.
All contact tips on the high current circuit of a relay are subject to arcing when they make & break.
Load current flowing through this constricted area generates heat which causes the contact material to melt, then boil / vaporise.
The liquified metal tends to collect on the cathode contact because that contact is cooler than the anode contact.
The relay manufacturer will compensate for this transfer by increasing the volume of material on anode contact; they may also choose a slightly different alloy for the cathode & anode contacts.
All this is carefully designed to extend the life of the high current contacts.
However start moving the electrons in the opposite direction, and the very feature designed to extent the life of contacts will actually significantly shorten it.
In fact it was Carl Baker that told me there is a right and wrong way to wire the relays, & TVR definitely got it wrong.
According to Carl the training given by Meta is very clear about the importance of the correctly wiring of components supplied by the relays inside their product.
This was the very same training Carl Baker received but TVR skipped.
I have no reason to doubt what Carl told me and what the manufacturer is teaching their agents.
Sam.
I had similar problems. Not sure the 70 degree was an issue for me, a red herring?. Had my META bridged since it was cutting out the ignition and fuel pump. B....y dangerous and lethal when it once cut out on a big busy fast roundabout. Lucky we survived. It still locks the doors ok and I dont need the nuisance of the alarm. No more worries over the past two years.
Did your motor restart on the emergency tab, after a short rest, like mine did before I had the META bridged?
I had similar problems. Not sure the 70 degree was an issue for me, a red herring?. Had my META bridged since it was cutting out the ignition and fuel pump. B....y dangerous and lethal when it once cut out on a big busy fast roundabout. Lucky we survived. It still locks the doors ok and I dont need the nuisance of the alarm. No more worries over the past two years.
Did your motor restart on the emergency tab, after a short rest, like mine did before I had the META bridged?
If its cutting out at 70 mph on the motorway I doubt for one minuite its AFM / ECU fuel related (unless the fuel pump is stopping- ie the fuel pump relay is faulty) As Spend says what does the rev counter do when it dies? If it drops to zero when the engine is still turning, its going to be ignition amp, or trigger to the amp.
Chimpafrolic said:
I totally understand what you are saying Loubaruch, ........But I am not referring to the low current control circuit, it's all about the flow of electrons through the contact tips on the high current side of the relay.
All contact tips on the high current circuit of a relay are subject to arcing when they make & break.
Load current flowing through this constricted area generates heat which causes the contact material to melt, then boil / vaporise.
The liquified metal tends to collect on the cathode contact because that contact is cooler than the anode contact.
The relay manufacturer will compensate for this transfer by increasing the volume of material on anode contact; they may also choose a slightly different alloy for the cathode & anode contacts.
...........According to Carl the training given by Meta is very clear about the importance of the correctly wiring of components supplied by the relays inside their product.
This was the very same training Carl Baker received but TVR skipped.
I have no reason to doubt what Carl told me and what the manufacturer is teaching their agents.
Chimpa frolic, many thanks for your detailed reply, and like you I have a great respect for Carl Baker the reasons stated are most interesting and quite plausible but I am afraid are in my opinon a fairy tale.All contact tips on the high current circuit of a relay are subject to arcing when they make & break.
Load current flowing through this constricted area generates heat which causes the contact material to melt, then boil / vaporise.
The liquified metal tends to collect on the cathode contact because that contact is cooler than the anode contact.
The relay manufacturer will compensate for this transfer by increasing the volume of material on anode contact; they may also choose a slightly different alloy for the cathode & anode contacts.
...........According to Carl the training given by Meta is very clear about the importance of the correctly wiring of components supplied by the relays inside their product.
This was the very same training Carl Baker received but TVR skipped.
I have no reason to doubt what Carl told me and what the manufacturer is teaching their agents.
If this was the case relay manufacturers would specify polarity for their contacts. RS components a major supplier lists relays from many manufacturers, some handling several hundred Amps, they list over 7000 relays and none state polarity for the contacts. I would doubt very much that Meta or any other alarm/immobiliser manufacturer would make their own relays, its so speciaised just not worth the effort, so they depend on what the market has to offer. TVR may have taken a few short cuts in their history but I fail to see that this is one of them. Perhaps they overloaded the relay contacts (especially) the starter solonoid ones) but that is nothing to do with reversed polarity.
I am quite happy to be proved wrong, but with facts not techno babble!
EGB said:
Sam.
I had similar problems. Not sure the 70 degree was an issue for me, a red herring?. Had my META bridged since it was cutting out the ignition and fuel pump. B....y dangerous and lethal when it once cut out on a big busy fast roundabout. Lucky we survived. It still locks the doors ok and I dont need the nuisance of the alarm. No more worries over the past two years.
Did your motor restart on the emergency tab, after a short rest, like mine did before I had the META bridged?
+ 1 Sam, techno babble and relay polarity asisde, your experience supports exactly what I'm suggesting could be source of the OP's cutting out problem.I had similar problems. Not sure the 70 degree was an issue for me, a red herring?. Had my META bridged since it was cutting out the ignition and fuel pump. B....y dangerous and lethal when it once cut out on a big busy fast roundabout. Lucky we survived. It still locks the doors ok and I dont need the nuisance of the alarm. No more worries over the past two years.
Did your motor restart on the emergency tab, after a short rest, like mine did before I had the META bridged?
I also had the Meta issue (starter circuit) so I simply bypassed it on that circuit.
Just like you I have not had a single problem since.
Given that faults with the Meta system are extremely common, and the fact it controls the fuel and spark, it has to be one of the potential suspects.
Lets hope our experiences help the OP solve his problem.
Have you access to a Land Rover V8 code reader?
It could be worth plugging one in to see if a fault code is registering.
If you feel like chancing a drive to Cumbria I have one and a spare AFM you could try.
Chimpaholics advice to bypass the Immobiliser is a good idea if you are unsure how to do this send me a PM
best of luck!
It could be worth plugging one in to see if a fault code is registering.
If you feel like chancing a drive to Cumbria I have one and a spare AFM you could try.
Chimpaholics advice to bypass the Immobiliser is a good idea if you are unsure how to do this send me a PM
best of luck!
Gassing Station | Griffith | Top of Page | What's New | My Stuff