Originally Posted by Johnny2R (Post 120064)

I bought my Rover 75 CDT in July 2006 and, after some initial problems with injectors, it has been a delight. Three times in that period, though, it has completely failed to start, and the worst and most serious instance was a couple of days ago. When I say failed to start, I mean it turned over OK, but nothing more, not so much as a cough. Normally it starts straight away without a problem.

Now, each time this complete non-starting has occurred, I believe I have, immediately prior to the non-start, done something slightly different from normal as regards unlocking the car - maybe accidentally re-locking it and then immediately unlocking it again, or something like that. Each time, the car has eventually just sprung back into life as if nothing had happened.

The other day, I had been for a short walk, then got back into my car and felt sleepy, so, deciding a short snooze might be in order, I pressed the button to lock all the doors. I then realised I probably wouldn't be able to sleep so decided to head off anyway and attempted to start the car, but no joy. I immediately thought "Ah, it's that old immobiliser mischief again", so did every permutation of locking, unlocking, getting in and out, etc, I could think of, but it still wouldn't start. I thought it must be something different this time, so called out the recovery people. Anyway, the guy couldn't work out what the problem was and could only determine that no power was getting to the under bonnet fuel pump (certainly I wasn't hearing the normal burring noise before starting). I took a look to see if the ECU was wet but the plenum was dry as a bone. Anyway, just after I'd put the ECU back into place, the recovery guy tried the ignition on and off three times in rapid succession, and bingo, it sprang back into life as if nothing had happened.

Now, it strikes me that this is likely some kind of immobiliser quirk, some bug to do with some sequence of actions which causes it to misbehave (unless there is some other explanation which someone can think of). Has anyone else come across such an immobilisation problem? And is there some way of effectively resetting the immobiliser, some sequence of key fob presses perhaps, that tells it to pull itself together and stop being silly?

Originally Posted by David3807 (Post 439511)

Hi Lynne and welcome to the club.

So that a more specific reply can be given can you let us know what model you have ?? Diesel ?? Petrol ??
If Petrol what engine - 1.8 ? 2.00 V6 ?? 2.5 V6.
Automatic or manual ? How old is the car and mileage.

EAch model can have different likely causes of non starting.

However one thing common to all is the battery. If the car is over six years old and is on the original battery then its on borrowed time.

Did you notice if the headlights flashed when you tried to start the car and failed ?? The cars computer (ECU) checks the battery power level every time before starting the car. If there is not enough in the battery the ECU will not allow the starting proceedure to continue and to let you know this will get the headlights to flash at least 3 times.

If this is the case and the battery is over six years old then it could be new battery time. If the battery is fairly new then it could be that you do a lot of short journies which has not given the battery enough time to recharge properly. Think it takes about 5 to 10 miles of running to replace the energy of ONE COLD start. A decent long run (once the car is running) or useing a battery charger every now and again might cure things.

HTH

Originally Posted by David3807 (Post 439511)

The cars computer (ECU) checks the battery power level every time before starting the car. If there is not enough in the battery the ECU will not allow the starting proceedure to continue and to let you know this will get the headlights to flash at least 3 times.

Originally Posted by Lynneth (Post 439798)

Thank you so much for replying

I have a Rover 75 1.8 petrol car.

I did not see any flashing of headlights, although it was daylight on the two occasions it failed, so may not have noticed.

Also, as previously mentioned, on both occasions, the car did start with no problem, then after stopping the engine for a short while (and removing the key from the ignition), it refused the start again because of the immobiliser.

As far as travelling is concerned, I travel long distances (all over the country) as part of my work, so there is no problem with that.

The car is six years old, so not sure if the battery is the same age as the car or not. It certainly does not seem to have been a problem, and has started every single time since I bought it - until recently. The car has done 60,000 miles (it had 33,000 miles when I bought it) and is manual.

Thank you very much
Lynne

Originally Posted by Lynneth (Post 439798)

Thank you so much for replying

I have a Rover 75 1.8 petrol car.

I did not see any flashing of headlights, although it was daylight on the two occasions it failed, so may not have noticed.

Also, as previously mentioned, on both occasions, the car did start with no problem, then after stopping the engine for a short while (and removing the key from the ignition), it refused the start again because of the immobiliser.

As far as travelling is concerned, I travel long distances (all over the country) as part of my work, so there is no problem with that.

The car is six years old, so not sure if the battery is the same age as the car or not. It certainly does not seem to have been a problem, and has started every single time since I bought it - until recently. The car has done 60,000 miles (it had 33,000 miles when I bought it) and is manual.

Thank you very much
Lynne