neon engine problems
stuntman19832000
07-06-2010, 07:15 PM
my mom has a 2000 neon and it has real bad miss. and it looses power when it misses, and the check engine light comes on. after it gets up to speed the miss stops and the check engine light goes off. Also it keeps fouling just one spark plug on the far right side of the engine, i think it's the number 4 plug. Any suggestions?
denisond3
07-06-2010, 07:48 PM
The plug is fouling because the compression is either too low (from a bad valve among other things, or from bad piston rings, or a damaged piston, or a head gasket leaking), or even because you have a fuel injector that is stuck open & making it run too rich. So trying a new plug and a new plug wire would be my first move. If it still happens, do a compression check. If that doesnt show up anything wrong, I think my next step would be to swap the fuel injector from the bad cylinder with another one -- and see if the plug fouling moves with the injector. If the oil control rings on the piston are bad, there could be a lot of motor oil coming up into the combustion chamber, and that would contribute to the plug fouling.
While the fuel regulator should hold fuel pressure for hours, even overnight, its not too bad if it no longer does; as long as it holds it okay while the engine is running. An injector jammed open would let the fuel pressure bleed off by peeing fuel into that cylinder.
If the problem is due to a head gasket going bad, it will get worse presently, and you may see scummy muck when you take off the radiator cap, or scummy muck showing up on the dipstick.
The 95-99 Neons were known for having feeble headgaskets as they came from the factory. Most of them have long since been replaced, a lot of them being done when the car was still under warranty. Its possible to tell if the headgasket was replaced, by finding the tiny round tab sticking out between the head and the block. You have to look behind the intake manifold tubes to find it. The replacement head gaskets were much much better - though even they might fail eventually (if some overheating had occurred). Im pretty sure they had fixed the headgasket situation before the 2000's came out.
While the fuel regulator should hold fuel pressure for hours, even overnight, its not too bad if it no longer does; as long as it holds it okay while the engine is running. An injector jammed open would let the fuel pressure bleed off by peeing fuel into that cylinder.
If the problem is due to a head gasket going bad, it will get worse presently, and you may see scummy muck when you take off the radiator cap, or scummy muck showing up on the dipstick.
The 95-99 Neons were known for having feeble headgaskets as they came from the factory. Most of them have long since been replaced, a lot of them being done when the car was still under warranty. Its possible to tell if the headgasket was replaced, by finding the tiny round tab sticking out between the head and the block. You have to look behind the intake manifold tubes to find it. The replacement head gaskets were much much better - though even they might fail eventually (if some overheating had occurred). Im pretty sure they had fixed the headgasket situation before the 2000's came out.
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