It all started with a blinking engine light that turns solid after a couple of minutes or after turning off the van and then restarting. It would reset itself after a couple of restarts. The code always says # 4 misfire. Have changed the sparkplugs and the wires. It now comes on much more often and has even started to idle rough at times. I've taken it to a mechanic who found nothing wrong, the engine light did not come on when he drove it. The EGR valve was taken apart and cleaned and no problems were found with it. He checked all of the cylinders and they checked out okay. I'm afraid to drive it very far from home. Any suggestions please? I hate to put more money into is since it has other problems such as front vents only work on high, rear ac only blows hot air, and my fuel gage no longer works. I hate to put money into something when the problems seem to be escalating but can not really afford a newer vehicle.
It does look like my coolant is going down and have read a little about the fliud may be leaking on the plugs, is there a quick way to check this?
Misfires can be caused by worn or fouled spark plugs, a weak spark (weak coil, bad spark plug wire), loss of compression, vacuum leaks, anything that causes an unusually lean fuel mixture (lean misfire), an EGR valve that is stuck open, dirty fuel injectors, low fuel pressure, or even bad fuel.
A Random Misfire code usually indicates a vacuum leak or bad gas.
If a misfire in a specific cylinder should lead you to check the spark plug, fuel injector and compression.