ok so i have put my code reader on my 97 civic ex which is auto, and sometimes it boggs when i am driving it and almost comees to a stall when i come to a complete stop. so the code read fuel trim malfunction (bank 1)
any suggestions on what to do or what it could be?

 

What I would try first is adding some Lucas Injector cleaner to the fuel. put 4 or 5 ozs. in & drive it. I have had good luck using Lucas. If it is a plugged or dirt injector or injectors it will help. The other thing is it could be a leaky injector.

 

so you dont believe it would be an 02 sensor. it feels like there is a lack of fuel to the accelerator which is weird. and i feel like i went thru a tank of gas extremely fast.

 

You were asking for a suggestion and you got it from 90Civic who, probably has not seen or felt your car.

If you believe it is the O2 sensor, go ahead and change it.

Faulty injector(s) make your engine go through fuel fast due to improper/insufficient combustion as well as faulty sensor.

I go with less expensive and easiest one first if I were you.

 

A common issue in 96-00 Civics is that the header will crack right down the middle, where the #1 O2 sensor is. Take your heat shield off first and look at that. A bad crack will leak a lot of exhaust, which leads to faulty readings from the O2 sensor, which might not actually be bad.

 

I think the EX has the different manifold which is not so prone to cracking, but it would be worth checking anyway. Hold a rag over the tailpipe with the engine idling and listen for exhaust leaking out anywhere.

Remove the spark plugs and inspect for one being fouled black, etc. which would indicate a problem related to that cylinder. Buy new plugs to go back in if they haven't been changed in a while.

Also disconnect fuel injectors one at a time with engine idling to check for dead cylinder.

It's simple to remove the injectors from the car and clean them rather than hope for some magic in the tank.

Stalling when coming to a stop is often an unrelated problem of a dirty IACV. Also whenever you lack power driving and get bad gas mileage, the cam and spark timings should be checked.

 

I was skeptical about fuel injector cleaner in tank for a long time. I have been back on this forum for couple of month, I read 90Civic recommending Lucas more than once. So I decided to give it a shot on my Accord since my Civic is still IN-OP. One small bottle divided in two fill-ups later, the engine is idling noticeably smoother than before.

So, I would say it worked for my engine.