Hi all

Water pump went out in my 90 accord ex (174k), sent it to the shop and it was fixed in a day. I figured while i was at it that i would give it a little tlc and maybe get the mpg's up. Ended up repacing spark plugs (ngk .044), thermostat, air filter, fuel filter, pcv valve, put fuel injection cleaner in before a full tank of gas, and replaced the battery because i let the other one go dead while she was out of commision[]. Well it runs much smoother now and seems that everything is in tact...until the car warms up. At that point she starts sputtering in the lower rpm range almost as if not getting enough fuel. If i step on the gas then she gets goin and it does'nt seem to happen in the higher rpm range. The check engine light has not come on.The reason i put in some fuel injection cleaner is because im sure that it has'nt been done in some time, if at all. My thought is that maybe the cleaner is working and some gunk is getting in the way, but i don't want to be drivin er if it's gonna mess things up more. I know that there are many people on here that know much more than i, any help or advice wouldbe much appreciated. Thank you!

 

As engine warms, the engine goes into closed loop operation at about 140F coolant temp. At this point, some information to the Engine Control Unit, may be faulty causing the engine to be starved for gas or flooded. Possibilities are 1) coolant or air temp sensor out of tolerance (its' still working but putting out poor info causing fuel mixture to be off, 2) O2 sensor (most likely suspect), or 3) manifold air pressure or atmospheric pressure signal.

I hope you replaced timing belts when water pump was installed, as they are due at 180K miles.

good luck

 

Thank you for your thoughts, ill replace the o2 sensor after work. I did'nt have the timing belt replaced because it was replaced at 150 k.

 

Ok, so after work i decided to rev the S*** out of it before i put any more $ into it. I got it on the freeway and almost red lined it in every gear! I then took it on some back streets and low and behold no more problems. She has been running perfect since then. So for anyone in the future... if you use fuel injection cleaner and your car starts to bog down, clear it the old fashioned way!

 

Sometimes a good ol' hard drive will make the engine give a good cough!