engine turns over but wont start
 

my 1990 mustang lx (4 banger) will turn over but wont start. it ran fine before i parked it for about 20 min then it wouldnt start again. it has brand new wires, plugs (gapped correctly), gets fuel in the cylinders, gets spark, fire order is correct, distributor has no visible cracks or excessive wear, and it has a brand new battery..someone please help..i cant think of anything (primarily cuz im not a mech)

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krashkool

If you are sure that it is getting fuel, has spark (a visible spark may be present but still have a bad ignition module), I would check the static timing to see if the cam drive belt has slipped or broken. It needs to be changed every 60,000mi.

Is this throttle body or port injection? I cannot remember the cutoff now. If is TBI, there was a problem with the injector hanging open dumping fuel. It would act just like a bad ignition module.

Sorry folks, 4 cylinders only came in MFI; TBI was for the 6 cylinders. The static timing issue holds pressure, but the engine ran before the problem occurred. I'd say timing is ok. A quick check to see if the belt broke would be to DISABLE IGNITION SYSTEM BY REMOVING THE COIL WIRE FIRST, then remove a spark plug and put your finger over the hole. Have an assistant turn over the engine. The engine should blow your finger off the hole (not hard-- you'll feel the pressure build first). This suggests the valves are moving with the crank; there's only one way that happens-- timing belt. I'd check the ignition module first, and the fuel pressure. It's getting fuel, but is it pressurized? Is the system staying pressurized when the car is off, or is there a leak down. Check this by opening the fuel filler door and have an assistant turn the ignition to the ON position (DO NOT START!!) listen for a high whirr sound. if there is none, you could have a fuel pump or fuel solenoid problem. If the whirr lasts more than a second, you may have a pressure problem. The correct sound should last a second and end sounding a lower tone like pressure is building against the pump. If this is not the case, you may have a problem with one or more injectors, or the fuel pressure regulator. Pull the spark plugs and see if they are wet. If they are, you've got too much fuel going into the cylinders -- injectors or pressure regulator. Also, if you smell rich fuel from the exhaust when you try to start the car, (strong enough to burn your eyes) I'd be willing to bet you have an injector or regulator problem. I ran into that with my '88 a while back when the two inside injectors decided to go. Car ran fine one day then never started ok again. I got it to run like crap at 3k rpm after changing the fuel pressure regulator, pump, and solenoid (located under the driver's seat), but the fuel smell drove me to my neighbor's house. Hope this helps.

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Pony Express 66
God Speed and keep it between the lines!