Hello all,

I have a 1997 Avenger ES 2.5 that just started running rough when the engine get hot. When I first start the car it runs fine with no miss. The engine light has been on for quite a while. When I took the car over to have the codes read I was told it was an oxygen sensor which I replaced and the light went off for a while. Now the light is back on and like I said the engine is running rough. The tach is steady but when you go to accelerate the engine has no power at all. The car has over 138,000 easy miles on it and being a former mechanic on gas engines, not fuel injection, I know a little bit about cars but cannot figure this one out. I replaced the front 3 spark plugs and they looked good.

I took the car back over to have the codes read again and was told this time that the code reader would not communicate with my computer as there was a bad fuse. I have never heard of this and have no idea where this fuse would be or how to fix it. Also, what possibly could be the problem with the engine running rough when it gets warm. Could it possibly be a coil when it gets warm and if so where would that be located?

Thanks for any help.

 

I forgot to mention that when the engine is running rough the engine light starts to flash and is not solid like it normally is if this helps.

Also, I just saw online that this car has 2 computer plugs, a 16 pin and a 12 pin plug. If the parts person at Auto Zone hooked up there computer reader to the wrong plug would that cause the "bad fuse" code to show up and not be able to read the codes.

Thanks again,

Glenn

 

I just got back from O'Reilly's and had them pull the codes for me and was told that #4 cylinder was misfiring. Is that the cylinder on the front head or the one next to the firewall? Also, I pulled the plugs on the front head and replaced them even though they looked fine. If #4 cylinder is up front what else could the problem be?

 

Injector, plug wire, distributer cap, rotor, burnt valve, or worn cam. From my research, it's the center plug on the front head near the radiator. I am having the same code and my plug wire was laying on a hose clamp and may have been shorting. Check wire and see if it is shorting on some metal..

 

could it be a temperature sensor? bad thermostat? blocked radiator? water pump working? Is water circulating? Turn heater on to help release some of the heat from engine but be sure to open windows so you don't get over heated yourself. No white smoke right?