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Q: What's wrong with my variable timing solenoid?

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took my 08 expedition to pep boys to check a engine light trouble, long story short the mechanic said the code was due to a variable timing solenoid he also noticed the passanger valve cover had a crack and a little oil came out, with no warning just ran a little rough could hardly feel it, engine temp never rose oil pressure never dropped truck only has 124,000 miles all maint up to date and all oil changes done on time, he freaked me out and said the motor was no good without even checking further... please help

My car has 124000 miles.
My car has an automatic transmission.

A: Hi there. I can certainly understand how yo...

Hi there. I can certainly understand how you were freaked out by what was said to you. However, no diagnosis is an exact diagnosis without uncovering the root cause of the failures. The variable timing solenoid could be sticking, failed, broken, have a broken wire, or the engine computer is not sending voltage. These solenoids run on a duty cycle that controls how much it opens/closes and controls the valve timing in this matter. Contaminated oil is probably the most common cause that I have seen in my history for the failure of these valves; contamination buildup causes the valve to stick and can create a rough idle or stumble.

Try a fresh oil change and check the duty cycle of the valve at the connector with a digital volt/ohm meter. As for the cracked valve cover, inspect it for an actual crack as this may simply be a leaking valve cover gasket. If the valve cover is cracked it may simply just need to be replaced. Remove the valve cover and check for impact damage at the source of the crack/leak. If there is no damage, then replace the cover and gasket. YourMechanic has several available technicians who can assist you with a Check Engine Light inspection and oil leak inspection.

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