D40 won't start after washing engine bay

[willym]

hi, Have a prob with my 2012 D40 auto. Just hosed out engine bay with hose, no pressure washer. Started OK, then spluttered and stopped. Restarted after a bit, seemed OK and decided to take it for a run to dry the engine bay out. Ran OK for about 10 minutes, then seemed to lose power, no engine lights or anything. Got it home and stopped it and now it won't start. Just cranks over. Checked the air filter, dry , no ingress. Did an ECU reset, no help. Any suggestions would be much appreciated. Thanks

 

[Old.Tony]

It's possible that the ECU earth was marginal (some of them haven't been very good at all) and that's causing the problem. ECU is high on the far right-hand side of the engine bay (my garage has a pic showing the location).

It might just be a poor connection on the battery itself. Clean the terminals and then measure the voltage before trying to start it again - you want to see 12.4V or higher.

 

[Bad Juju]

Pull the connector for as many sensors as you can and see if any are wet.

 

[happy john]

As above, I would pull all the connectors and spray with wd40. "If" you have a chip fitted the connectors can be a real issue with water.

 

[willym]

Thanks for the suggestions, I do have a chip fitted, so will give that a good look at.

 

[justbruce]

There is a connector for the wiring loom up behind the right hand mudflap. I've had water drip into this.
Disconnect shake and re-connect.

 

[shaunus88]

You didnt specify if it was diesel or petrol...

If petrol, pull out all the coil packs. That is usually the culprit for petrol engine faults after washing.

If diesel, I pressure wash mine all the time. It would no doubt be something simple. As above, i would be starting with the battery.

 

[LLadnar]

Any electrical connection can be coated in petroleum jelly or vaso. This will help keep water out of them. You can buy a proper sealant but vaso works fine just doesn't last forever.
Also a good trick for petrol motors for crossing rivers, but doesn't last long after out of the river due to heat.

 

[willym]

Just an update. Apparently, the hosing out the engine bay did not have anything to do with the limp mode. Next morning, the car started first turn of the key , but was still in limp mode but with the check engine light now on. RACQ put his decoder on and P1275 error came up - fuel pump. Towed to Nissan and the replaced the Suction control valve - seems OK now.