Slow to Fire Merc A150

[del mar]

Morning,

Battery has been ordered but not sure it is at fault.

135k on the clock, a little tired but regularly serviced.
New Coils and Plugs last year.

When you first start the car, the starter motor spins but it wont fire.

If you leave the car for with the ignition on for 10 secs, and then try again it will cough, leave it another 10 seconds and it will then start.

Almost like glow plugs warming up, but it is a petrol !

The starter motor never seems to lose any urgency, which makes me think it might not be the battery ?

Could the battery be strong enough to spin the starter but not supply a spark ?

Thanks

del

Young Mar used one of my car washing buckets to collect road salt !!!!!

[HustleRussell]

Possibly fuel supply? What is the fuel level? Perhaps the fuel filter is partially blocked or contaminated with water which has frozen?

[paintman]

Sounds more like fuel draining back to the tank when the car's left standing.
If it doesn't do it for the rest of the day when left for short periods then that would tend to confirm it.

Appreciate it's a diesel but I had exactly this with my Sprinter van a couple of years ago which turned out to be the small plastic valve on top of the fuel filter. Left overnight facing up a slightly sloping drive it took a fair bit of cranking but when restarted during the day - up to 7 hours - it would start as normal.

[E-bmw]

paintman said:

Sounds more like fuel draining back to the tank when the car's left standing.
If it doesn't do it for the rest of the day when left for short periods then that would tend to confirm it.

^^^^Wot 'e said.

Most likely fuel drain back, does the car have an electric fuel pump & if so can you hear it running with the door open & the ignition turned on but not starting the car?

If it does & you can hear it, leave it for a minute before trying to start & see if that helps.