I have a 2008 Roomster 1.2 Diesel. 150,000 miles. Its just passed an MOT and been serviced! It is getting older and over the past months and years more trouble starting. Its not left us stuck in a car park but that day is coming.

 

The battery is very strong and fairly new if I remember. I've cranked the ignition many times. Good strong response. Sounds like it might start but then it dies as I release the pressure on the ignition key.

However, if I am a little more insistent, I keep the key turned and feather the throttle (I tend to feel its just a little bit of pressure on the pedal, not flat to the floor) it starts and then runs like a beauty. I can usually do this on the second try to start. I can go for a ride, acceleration is as normal. Give it a bit of a rev and release and it returns to idle.

I've bought a simple OBD reader. No codes are ever generated. No engine warning light. When its running its MAP (kPa) is 99, RPM at idle 900, SparkAdv 63, ETC 58, ODB_Power 14.4v MAF between 6.5 and 8.5

 

I've looked under the hood and it was a little dirty, so I've cleaned it by brushing with a paint brush and vacumming and blowing with a domestic cleaner. No sign of wire damage. A few clips are broken but no sign of wear.

 

I think the clue is in the success when 'feathering' the throttle but what am I actually causing to happen when I do that? More fuel, less fuel, more fuel pressure, less... It used to be that a wire connected the peddle to the carburettor and change the air mix, but those days are long gone 🙂

 

Regards

Nick

Welcome.

 

How new is the battery if you can not remember?  It can not be that new. 

 

I hope someone can help. 

Sorry but i have no idea, other than you should not need to be touching the accelerator to have your diesel engine fire up.

Hi

Thanks for the response. As many of us have, I've lost track of entire years over the COVID period. The battery is about 4 years old. I've just used one of these clever battery charger/testers on it and it says the battery is fully charged and fine.

One extra thing that has happened is that will it was idling on the driveway, it simply stopped running. My wife tells me this has happened a couple of times before. I've had a suspicion this might be something to do with fuel supply and a bit of searching shows someone with an engine cutting out being caused by a temperamental fuel relay. A relay (there might be 2) is less than £20 so I think that’s my next shot.

Anyway, once again, thanks for your input.