Check engine light on?

Check for applicable codes. If it cranks good but won't start, have a helper crank it while you visually check for spark at the plugs. If you have spark everywhere, use a gage and check fuel pressure.

My advice is more about your relationship with your garage. You need to be taking it to someone who is trustworthy. Feel free to post as many times as you like to get an understanding of what is going on with your car. There are articles here that can provide good information on the check engine light.

The range is so wide as to what the problem may be. Codes need to be extracted from the computer for a start of the diagnosis process. What ever the problem is I would expect that this will be covered under warranty based on the age and milage of the car. The one exception is if you didn't tighten your gas cap the last time you put gas in.

We need the codes
so we can be able to help
post the codes

[quote="debra7147"]Have replaces the Idle air control Value the coil pack and the air filter. The code is P0507. Thanks Debra[P0507-IDLE SPEED HIGH PERFORMANCE
When Monitored: Engine Running. During an idle condition.
Set Condition: If the engine RPM does not come within a calibratable high limit of the target idle speed, a failure timer will increment. When the appropriate failure timer reaches its maximum threshold without sign of RPM trending towards control, a soft fail is generated. When a calibratable number of the soft fails is reached, a 1 trip fault is set. When two 1 trip faults occur in a row, the DTC is set and the MIL illuminates.
POSSIBLE CAUSES
à   GOOD TRIP EQUAL TO ZERO
à   PCV SYSTEM
à   IAC MOTOR PASSAGES
à   VACUUM LEAKS
à   AIR INDUCTION SYSTEM
à   THROTTLE BODY AND THROTTLE LINKAGE /quote]

The first thing is to have the diagnostic fault codes read and recorded. The people at many auto parts stores will do that for you for free.

Driving with the Check Engine light on is a very bad idea. The Engine Computer detected a problem that could be relatively minor, but it could turn into an expensive one if the cause is ignored. Even when the cause is determined to be not real serious, you would never know if a second, really serious problem develops because the light is already on.

You can get an idea of the severity of the fault code by how the Check Engine light acts. When the problem is intermittent and not serious, the light will go off when the problem stops occurring. If it's a little more serious, the light will stay on, even when the problem goes away, until you stop and restart the engine. When it's more serious, even though it may not be acting up right now, the light will be on anytime the engine is running. Those are the ones that can cause other expensive repairs. The really bad problems cause the Check Engine light to flash. That means stop the engine right away because serious damage is occurring right now.