[gaz1250]

Long story but here goes....got a focus 1.6 it was runnin perfect until the other week when it started to misfire new coil but no diff so turned out to be water in the spark plugs (a think that came from the engine bay being cleaned) changed the plugs and leads and got rid of all water. 2 days later the car struggled to start when cold and then temp sensor went...so after replacing the sensor the cold start problem went and no water returned sorted but now the car vibrates when idle (sat at lights etc) and gets worse when you use your lights, wipers etc. Ive tested the battery and voltage is ok so assuming alternator is fine. Help this car is drivin me mad!!! Thanks in advance

 

[whynotthinkwhynot]

Did you check the voltage across the battery terminals with the engine idling? This will give you an indication of what the alternator is putting out. For example, testing the battery with the engine off: 11.5v, engine on: 13.5v. That's a good alternator. Now if the reading is lower, but still more than 12v then you might have an old alternator. I'd remove the part, take it to a parts store, and have them test it's load capability. You might be able to see what 's going on yourself by turning on the lights, wipers, and anything else electrical you can think of, and compare that to the voltage readings with less load on the alternator.

Before you go all the way with testing or with purchasing a part- check all the things that are free first. Any time you have electrical problems you should check the battery terminals, and the battery cable connections to make sure corrosion or looseness is not causing your problem.

 

[gaz1250]

The voltage is comin out at about 14.8 when idle. Could a damaged cat cause vibration etc as if was quite a bad misfire when the water got in?

 

[Grumpy]

The alternator output looks OK. I would still check the battery connections for being clean/dry and tight. It sounds like this thing still has a slight miss at idle at least. Are you sure that "everything" has been dried out. Coil connections, crank pos. sensor, MAF connector, etc. and all other associated fuel delivery system connectors. I can't see how the cat could get water in it?

 

[gaz1250]

I will check other connections for water but Im pretty sure everything is dry. As for the Cat Ive read that a misfire can cause damage to the cat due to fuel burning in it? (Sorry not water that was badly written in earlier post)

 

[djmontara]

check for vacuum leaks.. vibration at idle is the main telltale of a vacuum leak.. check the pcv hose and other small hoses on the intake manifold. theres one small one on the back of the throttle body thats notorious for cracking...

 

[nilskje]

Seems like the car is running on 3 at idle, it sounds like the coilpack is about to go bad, every time i cleaned the engine bay I had to cover the coilpack (unless it was less than a year old). And they are so known to go bad on 1,6l.. Also replace the plug wires...