Hot start issue - help needed
Discussion
I have a 94 plate Chimaera that I have owned for just over a week. On 3 occasions now it has failed to start when hot. Once when the car had been locked and left, and twice when it had just been left unlocked. It has started every other time, hot and cold without any issues. I know from reading previous posts that the hot start issue has been well discussed, but I am not convinced that my problem fits the previously discussed Meta Alarm issues or not.
When I purchased the car I was relatively confident I would not have the host start problem given it appeared to be running a Scorpion rather than Meta alarm.
When it fails the fuel pump is running (fairly sure about that - but questioning my recollection as I write this), but the engine does not turn over at all and the bottom red LED between the speedo and rev counter stays lit. Arming and disarming the alarm makes no difference and it appears to arm and disarm ok. There is a blue LED next to the ignition key that flashes when the key fob lock and unlock is pressed and that appears to work as normal and the doors lock and unlock but the car will not start.
The alarm key fobs say Scopion on the back, and have 4 buttons - boot release, unlock, lock and siren (flash lights) the main key appears to be just a key and nothing special. The boot release works about 75% of the time - not sure if that is me or the system. The door unlocking works every time.
The car has a megasquirt ECU - not sure if that has any bearing on this problem.
Each time it has failed I have not been in a position to start doing any fault finding while it is faulty, and after a few (no more than 10) minutes the car starts as normal.
Over the last two days, armed with loads of useful advice from the forums I have started trying to work out what is wrong, which is difficult when then car starts every time while I am trying to find the issue.
I cannot find any sign of a previously fitted hot start kit relay. Based on what I have read, there may well be other issues that need resolving anyway, but I accept this may be a solution.
What is slightly more odd, is that I cannot find any sign of an alarm box or siren. I tried starting the car with the doors locked using the key fob, and it does not start and no siren either. I know therefore that an immobiliser is hidden somewhere. I have lifted the left side of the top dash and found the door control box, various relays but no alarm box as expected. Also lifted the centre console and found a small alarm sensor box but not sure if that is part of the current system or not. There were two in my S3 and neither were live. Finally I remove the stereo and had a look behind that, and nothing. It is entirely possible that the alarm box is very well disguised and I have just missed it or mistaken it for something else.
What I did find behind the passenger side footwell end panel was that somebody had zip tied the wiring loom to the heating pipes, which is surely asking for trouble, or is that normal?
I also found that several fuses were not pushed all the way in, and were partly out. Not enough not to work, but I have pushed everything in tightly.
Any advice on what to try next would be appreciated? I am reluctant to start throwing money at buying replacement start motor, alarms, etc without really knowing where the fault is.
Does anyone have a circuit diagram for the hot start fix - it might be worth giving that a try.
Although I like the central locking and key fob door unlock, I am less bothered about retaining the immobiliser especially if it is going to cause problems. The car does not appear to have a siren anyway. How easy/practical is to remove the immobiliser feature but retain the door locking?
Annoyingly I will not know if it is fixed or not until it fails again.
When I purchased the car I was relatively confident I would not have the host start problem given it appeared to be running a Scorpion rather than Meta alarm.
When it fails the fuel pump is running (fairly sure about that - but questioning my recollection as I write this), but the engine does not turn over at all and the bottom red LED between the speedo and rev counter stays lit. Arming and disarming the alarm makes no difference and it appears to arm and disarm ok. There is a blue LED next to the ignition key that flashes when the key fob lock and unlock is pressed and that appears to work as normal and the doors lock and unlock but the car will not start.
The alarm key fobs say Scopion on the back, and have 4 buttons - boot release, unlock, lock and siren (flash lights) the main key appears to be just a key and nothing special. The boot release works about 75% of the time - not sure if that is me or the system. The door unlocking works every time.
The car has a megasquirt ECU - not sure if that has any bearing on this problem.
Each time it has failed I have not been in a position to start doing any fault finding while it is faulty, and after a few (no more than 10) minutes the car starts as normal.
Over the last two days, armed with loads of useful advice from the forums I have started trying to work out what is wrong, which is difficult when then car starts every time while I am trying to find the issue.
I cannot find any sign of a previously fitted hot start kit relay. Based on what I have read, there may well be other issues that need resolving anyway, but I accept this may be a solution.
What is slightly more odd, is that I cannot find any sign of an alarm box or siren. I tried starting the car with the doors locked using the key fob, and it does not start and no siren either. I know therefore that an immobiliser is hidden somewhere. I have lifted the left side of the top dash and found the door control box, various relays but no alarm box as expected. Also lifted the centre console and found a small alarm sensor box but not sure if that is part of the current system or not. There were two in my S3 and neither were live. Finally I remove the stereo and had a look behind that, and nothing. It is entirely possible that the alarm box is very well disguised and I have just missed it or mistaken it for something else.
What I did find behind the passenger side footwell end panel was that somebody had zip tied the wiring loom to the heating pipes, which is surely asking for trouble, or is that normal?
I also found that several fuses were not pushed all the way in, and were partly out. Not enough not to work, but I have pushed everything in tightly.
Any advice on what to try next would be appreciated? I am reluctant to start throwing money at buying replacement start motor, alarms, etc without really knowing where the fault is.
Does anyone have a circuit diagram for the hot start fix - it might be worth giving that a try.
Although I like the central locking and key fob door unlock, I am less bothered about retaining the immobiliser especially if it is going to cause problems. The car does not appear to have a siren anyway. How easy/practical is to remove the immobiliser feature but retain the door locking?
Annoyingly I will not know if it is fixed or not until it fails again.
Pretty sure your car would have originally had the foxguard alarm system, someone may have changed it to the scorpion to modernise and have the boot opening feature.
You could test at the starter solenoid when cranking for 12 volts then at least you would have a direction to go in, tracing the cables back from the dash mounted led may help with the control module location.
You could test at the starter solenoid when cranking for 12 volts then at least you would have a direction to go in, tracing the cables back from the dash mounted led may help with the control module location.
If it's not the immobiliser (and it does sound like classic hot start immobiliser issue), the next likely culprit is the cable from battery to starter. It passes over the gearbox/back of engine and gets fried and crispy with the passage of time and all that heat. Resistance is increased by distance and temperature, hence not enough juice is getting to the starter for it to start when hot.
The starter solenoid can also break down with heat and time.
I have a hot start mod that I fitted to my car - my first hot start incident was one hour after buying the car - but it was removed by Carl Baker when he fitted me a complete new alarm immobiliser. No problems since then. It's sitting on the shelf in my man cave, looking lonely. You are welcome to have it for free.....I don't have the wiring instructions, but i am sure that you can get those from someone who has fitted the kit recently by appealing on here. Dave Beer, who makes them, might also email you a copy - he's a decent guy.
Just PM me your address and it's on its way to you (or call in and see me for a cuppa at Newark).
The starter solenoid can also break down with heat and time.
I have a hot start mod that I fitted to my car - my first hot start incident was one hour after buying the car - but it was removed by Carl Baker when he fitted me a complete new alarm immobiliser. No problems since then. It's sitting on the shelf in my man cave, looking lonely. You are welcome to have it for free.....I don't have the wiring instructions, but i am sure that you can get those from someone who has fitted the kit recently by appealing on here. Dave Beer, who makes them, might also email you a copy - he's a decent guy.
Just PM me your address and it's on its way to you (or call in and see me for a cuppa at Newark).
cp81 said:
Anyone got a picture of this kit installed?
I think its installed on my car but not too sure. Yesterday it would start, after a drive to country pub. Fuel pump primed fine but nothing from starter motor.
In three years its never done this.
Not got a pic, sorry. It's a relay and a fuse that sits in the rats nest near the battery.I think its installed on my car but not too sure. Yesterday it would start, after a drive to country pub. Fuel pump primed fine but nothing from starter motor.
In three years its never done this.
You sure you haven't got one of those breathalyser thingies installed that won't let you start the car until you have blown into it??
this might help with identification http://www.chimaerapages.com/install-hot-start-kit...
Should you have another instance of not starting,
Assuming you can hear the fuel pump prime but the starter isnt cranking try putting the car in 3rd gear and rock it back and forth a few times take it out of gear and attempt to start it, if it now turns over it looks like the starter solenoid is sticking rather than immobiliser issues.
Assuming you can hear the fuel pump prime but the starter isnt cranking try putting the car in 3rd gear and rock it back and forth a few times take it out of gear and attempt to start it, if it now turns over it looks like the starter solenoid is sticking rather than immobiliser issues.
As QBee said, it may be the live feed from the battery to starter. However, I would also check your battery output and clean all your accessible earth cables first (battery terminal, off-side wheel arch, transmission tunnel, behind nearside cyclinder head).
A good test to begin with is to get the battery out of the footwell, test the battery and clean the terminals, ensuring they're not corroded and are securely fastened. If this doesn't work, leaving the battery cables attached, try clamping a jump lead to the negative terminal of the battery and the other end to a clean earth on the chassis/ block. If it starts, you know you have an earthing issue. If this doesn't resolve it, try the next step.
If you have a spare battery or very long jump lead, place the car into neutral, remove the leads from the coil packs, jack up the drivers side and connect the jump lead to the live terminal of the battery and then the terminal bolt on the starter. If it turns over, you've pretty much ruled out a starter issue and it could be the live feed.
If it passes both the above tests and you're certain it isn't the alarm, then it is more likely to be a breakdown in the live feed cable from the battery to the starter. If the cable is begining to fail, then there is a higher probability of it doing so when the cable is hot and it's electrical resistance at its highest. ChimpOnGas has done a how-to guide on replacing the live feed. I did this and added two new earths. No issues since.
However, I also understand that the MS has three earthing terminals that should be secured to the bolt on the rear of the nearside cylinder head, between the bulkhead. I would definitely check these too, assuming that the MS install was done correctly.
See below for Dave's guide to the live feed. HTH
http://www.pistonheads.com/Gassing/topic.asp?h=0&a...
HTH.
Cheers
Chuffy
A good test to begin with is to get the battery out of the footwell, test the battery and clean the terminals, ensuring they're not corroded and are securely fastened. If this doesn't work, leaving the battery cables attached, try clamping a jump lead to the negative terminal of the battery and the other end to a clean earth on the chassis/ block. If it starts, you know you have an earthing issue. If this doesn't resolve it, try the next step.
If you have a spare battery or very long jump lead, place the car into neutral, remove the leads from the coil packs, jack up the drivers side and connect the jump lead to the live terminal of the battery and then the terminal bolt on the starter. If it turns over, you've pretty much ruled out a starter issue and it could be the live feed.
If it passes both the above tests and you're certain it isn't the alarm, then it is more likely to be a breakdown in the live feed cable from the battery to the starter. If the cable is begining to fail, then there is a higher probability of it doing so when the cable is hot and it's electrical resistance at its highest. ChimpOnGas has done a how-to guide on replacing the live feed. I did this and added two new earths. No issues since.
However, I also understand that the MS has three earthing terminals that should be secured to the bolt on the rear of the nearside cylinder head, between the bulkhead. I would definitely check these too, assuming that the MS install was done correctly.
See below for Dave's guide to the live feed. HTH
http://www.pistonheads.com/Gassing/topic.asp?h=0&a...
HTH.
Cheers
Chuffy
Edited by Chuffmeister on Tuesday 5th May 10:40
My car failed to start yesterday when hot for the first time in 9 years of ownership 
when I nipped hoke to pick something up. Fortunately this meant it failed on my driveway.
The fuel pump primed healthily (you can usually hear when the current is low by the tone of the pump) but when the key was turned - nothing.
I had bought replacement relays (as a percaution before driving to Italy last year) so swapped them - no joy.
After 20 minutes the car started so I drove it into the garage and onto the ramps.
I moved the batery to the boot last year and used hydraulically crimped larger gauge cable so I think its unlikely to be the problem.
I suspect the solenoid but didn't have time to remove it to test it and probably won't be able to look at it until early next week so will be watching this therad for any other ideas before I pull the starter. I understand its not easy to get at.
when I nipped hoke to pick something up. Fortunately this meant it failed on my driveway.The fuel pump primed healthily (you can usually hear when the current is low by the tone of the pump) but when the key was turned - nothing.
I had bought replacement relays (as a percaution before driving to Italy last year) so swapped them - no joy.
After 20 minutes the car started so I drove it into the garage and onto the ramps.
I moved the batery to the boot last year and used hydraulically crimped larger gauge cable so I think its unlikely to be the problem.
I suspect the solenoid but didn't have time to remove it to test it and probably won't be able to look at it until early next week so will be watching this therad for any other ideas before I pull the starter. I understand its not easy to get at.
Smokey Boyer said:
Can you elaborate a bit on the waterproof relay solution please SiliconeKid. I assume this is to bypass the immobiliser circuit???. If you have a part number and link for the relay and relay holder, that would be very good, as would a circuit diagram (rough sketch will do).
Its not an immobiliser bypass but is the hot start kit fitted in a different location, basically a relay in the starter solenoid circuit that tvr failed to fit.Tyre Tread said:
My car failed to start yesterday when hot for the first time in 9 years of ownership when I nipped hoke to pick something up. Fortunately this meant it failed on my driveway.
The fuel pump primed healthily (you can usually hear when the current is low by the tone of the pump) but when the key was turned - nothing.
I had bought replacement relays (as a percaution before driving to Italy last year) so swapped them - no joy.
After 20 minutes the car started so I drove it into the garage and onto the ramps.
I moved the batery to the boot last year and used hydraulically crimped larger gauge cable so I think its unlikely to be the problem.
I suspect the solenoid but didn't have time to remove it to test it and probably won't be able to look at it until early next week so will be watching this therad for any other ideas before I pull the starter. I understand its not easy to get at.
How old is the battery? Have you checked the voltage, mine failed to start and it was just the battery was slightly down on power, with moving it to the boot with a longer cable it will be more susceptible to problems with voltage drop. when I nipped hoke to pick something up. Fortunately this meant it failed on my driveway.The fuel pump primed healthily (you can usually hear when the current is low by the tone of the pump) but when the key was turned - nothing.
I had bought replacement relays (as a percaution before driving to Italy last year) so swapped them - no joy.
After 20 minutes the car started so I drove it into the garage and onto the ramps.
I moved the batery to the boot last year and used hydraulically crimped larger gauge cable so I think its unlikely to be the problem.
I suspect the solenoid but didn't have time to remove it to test it and probably won't be able to look at it until early next week so will be watching this therad for any other ideas before I pull the starter. I understand its not easy to get at.
Mine is in the boot, but it is a gel battery now. Wired direct to the starter by the guy who did the job, thus avoiding the hot section over the gearbox. Neat job. Starter turns at a hell of a rate.
I still have my 2 year old standard battery if you want to try it at the weekend, in case yours is knackered.
I still have my 2 year old standard battery if you want to try it at the weekend, in case yours is knackered.
PRTVR said:
How old is the battery? Have you checked the voltage, mine failed to start and it was just the battery was slightly down on power, with moving it to the boot with a longer cable it will be more susceptible to problems with voltage drop.
Battery is a couple of years old Odyssey925 so have every faith in it.For those suggesting an additional relay is the answer Abacus alarms says (http://www.abacuscaralarms.co.uk/re-coding-meta-alarms/tvr.html):
The car fails to start when the engine is hot (TVR's)
The M36T2 immobiliser is a two circuit Thatcham approved immobiliser, it is manufactured with very high quality components to a very high standard & as such this is one of the most reliable immobilisers manufactured today, many of these systems are still working perfectly on vehicles which are well over 15 years age.
The problem, relay 1 (circuit 1) of the immobiliser can handle a maximum of 10 Amps, relay 2 (circuit 2) can handle 25 Amps. Here's the rub, TVR have wired these circuits the wrong way around, the TVR fuel pump circuit goes through the higher rated relay 2, while relay 1 (rated 10A) has to handle the starter circuit. All being well there are no problems even though the two relays are wired the wrong way around, as testified in that they've been functioning perfectly for 10 years or more. Problems arise when the starter solenoid begins to wear, in so doing it demands more & more power to function, when the current flow to the starter gets to the 10 Amp limit of relay(1) problems start, this gets exasperated when the engine is hot which in turn makes the solenoid hot which in turn requires even more power, I understand this is known as the hot start problem, this demand for power will eventually burn out the smaller relay. Adding an extra 'hot start' relay to this circuit is not a premanent fix, this circuit will just demand more power which could eventually burn out the ignition switch or associated wiring to eventually the failure of the starter itself. Before this happens we recomend to have the solenoid/starter inspected & have it repaired or replaced if found faulty.
All replacement TVR adapted M36T2 immobiliserw will now be sent out with the immobiliser circuits switched to match the TVR wiring, this will now match the higher rated relay to the starter circuit of the TVR, this should cut down on the hot start issue
Smokey Boyer said:
Can you elaborate a bit on the waterproof relay solution please SiliconeKid. I assume this is to bypass the immobiliser circuit???. If you have a part number and link for the relay and relay holder, that would be very good, as would a circuit diagram (rough sketch will do).
Remove the solenoid cable from the starter motor and fit it in to 86connect a live cable to starter live (cable which comes from the battery)Then connect to 87 ether with an
in line fuse or a connector block with one incorporated .
fit a ground cable from the starter ground or chassis to pin 85
fit cable from solenoid connection on starter to number 30 .
Tie wrap out of the way .
This is what I did when upgrading my fuel pump feed ,same idea .
use heat shrink ,heat resistant sleeve ,what ever you want to make a tidy job .
If you can`t solder buy these
http://www.ebay.co.uk/itm/10-BLUE-HEAT-SHRINK-SOLD...
Edited by SILICONEKID345HP on Tuesday 5th May 22:06
Thanks for all the suggestions, and to QBEE for offering to help out with some bits. I have plenty to go on now for the diagnostics and will keep you all updated on progress when I have some time to work on the car again over the next few evenings (weather permitting as I can only just open the car doors in the garage.)
I think the probelm with diagnosing the issues on the hotstart problem is the fact its intermittent and you never know when or where it will happen. Then, after 20 minutes all is well again.
When people then go poking around to try and find the issue so many things are changed - connections tightened and cleaned etc- that it becomes unlear what solved the issue.
When people then go poking around to try and find the issue so many things are changed - connections tightened and cleaned etc- that it becomes unlear what solved the issue.
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