carlton start problems - wavyframe
I have a 92 carlton diplomat which has an intermitant starting problem normally she starts fine from cold but after driving 10-12 miles i stop and then attempt to restart with no luck, the engine cranks ok but will not fire, the car has a switchable auto box and the "sport mode light" flashes when the engine wont start.
If i leave it for 20-30 minutes and try again she starts right away, i have checked all the usual stuff ht leads battery connections & so on.

Everything seems to suggest a problem with the E C U

I would be extremly gratefull for any suggestions thanks and a merry christmas.
carlton start problems - Phil G
Try the Senator Yahoo group, a lot of these problems have been solved:
carlton start problems - Dynamic Dave
Separate ECU's for the engine & gearbox, IIRC.
Usually the main cause of the "sport mode light" flashing is that moisture has got into the gearbox selector switch on the gearbox and is triggering false signals to the ECU. With the light flashing you can usually still drive the car, but you have to treat the gearbox as if it were a manual box and do all the gear shifting manually.
Can't see how that is stopping the engine from running though.
Does the engine ECU light come on at all?
Again, IIRC, the Engine ECU stores faults for up to 20 ignition key turns, but the gearbox ECU doesn't store faults. That was what I was told when my Auto Cavalier played up.
carlton start problems - wavyframe
Thanks for your reply, i have heard the same story re the gearbox selector switch and all the evidence seems to point in that direction, however the sport mode light only flashes when the engine will not start (cranks over but will not fire) as soon as the engine starts the light goes out (or is it the other way round ??)after this the gearbox works fine.

The ECU light does not come on apart from the usual check when the ignition is first turned on.

Once again many thanks for your help.
carlton start problems - wavyframe

Just tried to start it from cold & guess what ??? yep now its the same starting problem as above, again go away for half an hour have a cup of tea come back turn the key and off she goes i have a feeling i have a can of worms here !!!!!!!

Tried looking at the Senator yahoo group thingy and their was one guy who had a similar problem with a carlton but no solution found there...

O well wheres my toolkit..
carlton start problems - Tony
Had similar problem on my Carlton, turned out to be the fuel pump relay, this has auxillary contacts that can burn out, located either in engine bay under plastic cover over near side wheelarch or in drivers foot well next to ECU, remove carpet by right foot below bonnet catch. Try another relay for 20 quid first if not other dodgy connection.
carlton start problems - wavyframe

Thanks for your advice i will check this out as it certainly seems one of the cheaper options and is something i can fix myself.

Did you have the similar problem with the flashing gearbox light as well?.

Thanks again.
carlton start problems - Tony
Yes, and it finally started but I had to manually select first then nudge it up the gears, still with the flashing light.
The auxillary contacts can be found on the wiring diagram but its not obvious what they do apart from stopping the engine from firing up.
I had this on a 90 model & it was in 93 that I was told that that relay had been superseded by a newer version & should have been changed at service for free, mine was not. If your relay is grey in colour, change it, later ones black.
carlton start problems - wavyframe
Cracked It !!!!!!!!!!!

Thanks to Tony following his advice i checked the relays that live under a plastic cover in the engine bay, sure enough when i started checking them i found one had almost melted where it plugs in and the connections had become covered in gooey melted plastic, when the engine got hot a little bit more melted and prevented contact.
This would not stop it running but if you stopped the engine it would not start again.
As a temp solution i have just wiped the contacts but will need to get a new relay.

Many thanks to everyone for all your help & suggestions
carlton start problems - pete. t
Carlton's do tend to have this starting problem, having personally tried all sorts with these, even to the extent of pulling the E.C.U,fuel pump relay & fuel injection system to pieces nothing seems to work. What does normally work is as follows: Press accelerator pedal about half way and hold it there, start the engine and when it fires up and revs go high i.e at least over 2,000 r.p.m, then pull your foot of the accelerator quickly and let the car find it's idle speed itself,
N.B if you let the pedal up slowly, it will cut out, so it is important to let your foot off the gas pedal as quickly as you can. Hope this works for you.
carlton start problems - wavyframe
Thanks for your advice i will check out this solution as soon as i have tried the other replies, i want to try one solution at a time so i can be sure i got the right one.
Interestingly enough the problem has not happened for a few weeks now (why do i get the feeling i shouldnt have said that) BIG thanks to everyone for your help and advice i will keep you posted


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