I Have a rough idle and have been checking over the car.

These are my symptoms..

Using a timing light.

Cylinder 1 is firing normally, but the timing mark can vary 10mm at idle.

Cylinders 2 &3 are normal not sure of the amount they vary

Cylinders 4, 5, & 6 all seem to be firing at about 1/3 of the speed of 1, 2 and 3.

Checked the codes, I only get a cam angle sensor code, but I dont think this could cause 1,2 and 3 to be normal while 4,5,6 are not, suggestions?

thanks

Cory

this has been covered a few times before. maybe not your exact problem with the timing light but ef rough idle.

Take of your crank angle sensor (2 bolts its behind the harmonic balancer) and give it a clean with some degreaser. Usually they are covered with gunk/grease.

If you haven't replaced the spark plugs within the last 10,000km change them. Also if the leads are more than 1 year old replace them too. This is just the usual stuff.

I have an ef fairmont, when i bought it, it had a rough idle now it idles perfectly. Usually the idle isn't so perfect when in PARK but in DRIVE they usually all idle better.

I also fitted a plastic spacer under the ISC, my car is on gas but it may help you as well. It re-routes the pickup for the PCV valve so it is in a central spot. The factory pcv connection on the manifold makes cylinders 2&3 run a bit leaner than the rest. The plastic spacer smoothes out the idle.
The part number from ford if you need it is AUC 9B571 A - KIT IDLE SPACER.
I had to drill 2 holes into my spacer as the ISC bolts are different between the AU & EF.

Before I converted to straight gas my EF had a faulty cam sensor too.
I never ever fixed it, i just left it disconnected when i switched to gas.
I would say that you will have to replace it if you want the idle 100%.
Good luck finding one from the wreckers that isnt stuffed. I think they are probably all dead by now. It seems to be a very common problem.

On that note, Ford claim not to sell them any more (discontinued), and I rang Bosch to see if they made them - they said they don't, yet guess what name is cast in the original part?