Sometimes starts then dies instantly then takes 2 secs to start. Why?

[_Alex_D_]

I have a Mk2 ph1 172. I don't drive it much. 50% of time in a garage.

I always give it a second to tick over and never thrash it cold. The oil is clean enough but about to change filter and oil to full synth since I don't know what the poor garage used for the service that they apparently did (but I don't believe.)

I've changed the air and pollen filter after recent aircon fixing (new condenser and dryer) and will do oil soon.


Anyway it has a sigma cat1 alarm imobiliser. Sometimes when I go to start it fires up and dies instantly after. Then when I try again (without touching immobilser button) it will start after two seconds. Had plugs changed at 69k and is on 100k now. Should I be looking at changing the plugs or is something else causing the problem. I mean is only happen 1 time out of 10 but it worries me.

Could it just be the amount of time it's sat. I don't think so because it always starts first time when sat and more so happens when I have drove it and then started it two hours later. I does sit for days though often.

Thanks for any help!

 

[_Alex_D_]

Brought some Bosch Super4s. Waited for them to come. Hope that will help.

No one got any comments?

 

[DaveLiquid182]

I think that is fairly common. My Mk2 ph2 172 did it, & my 182 does it sometimes.