only 3 cylinders when warm....any ideas??

[f7r cw]

my williams 3 runs fine when started from cold, but when warm engine is only running on 3 cylinders. changed leads plugs dizzy ignition coil etc, still only 3 cylinders.

When on 3 cylinders i remove ignition leads one by one all make engine drop power as expected exept for number 2 which stays the same. i suspect low compression getting test done on wednesday. Any ideas??

thanks

[16v_paddy]

Dodgy plug on the injector perhaps?

[diditno]

Maybe the cold start injector is compensating for a non working injector, ie when the cold start shuts off, only 3 work. Not sure what temp the cold start will work at, but may be worth a go.

[16v_paddy]

iirc the cold start injector doesn't do anything unless it's well into double figures below freezing outside

[f7r cw]

ill check out the injector, hopefully its this otherwise might be looking at valves and getting head reskimmed

[Wobba]

Check the most simple things first before going mad. Comp test, oil in plug wells, earths, clean crank sensor, try spare ECU if you have one too.

I've had my fill of misfires...

[dhay14]

could be the headgasket too... as when metal gets warm it sets out.

[f7r cw]

ok will check the simples first, no spare ecu though. getting comp test wednesday eve let you know how it goes. thanks

[f7r cw]

Problem solved!! i hope. Compression test was good 180 across all 4, on closer inspection the connector that goes into the injector from ecu had a loose earth, pushed earth in plugged it in and all 4 cylinders kicked in. drove it on and off for few hours and seems ok.