98 Grand Marquis Hard Starting and low idle speed

Pinging is likely due to a dirty MAF.

It's not inconceivable that a cheap version of the Idle Speed Control would hang up.. bad luck, sure but not real rare, I'd think. Where did you get it?

Thanks for your reply. I'm no sure what the MAF is. Is it the air filter? The idel speed control was replaced by my mechaninic and I assume it came from a decent auto parts distributor.

It's located between the airfilter and throttle body. It measures air mass into the engine for mixture tuning purposes. If it's dirty it will give a false low reading, which will result in less fuel to actual air, thus lean, thus ping. USUALLY dirty MAF has little to no effect on idle speed, but may cause stumble on acceleration from idle under load, like at a light.

Idle speed control only controls the engine speed by adjusting air admitted till speed is correct.

The MAF (Mass Air Flow) is located right behind the air filter. On my

Yours should be in the same location.it's a plastic pipe going to the engine's intake, and has a connector on it.

also....look at the throttle bore, if its dirty-clean it.