Lately my 1994 Hatchbox with the stock D15B8 has been lagging on the freeway a little bit and will require some extra gas pedal to get it to "break free" and drive like a normal car. I guess it hesitates and doesn't seem to take any throttle input, like it's stuck.

The interesting thing is occasionally the check engine light will come on and the car will drive perfectly fine immediately once the light comes on. Now, when I go to check what code its throwing me, I'll turn the car off, jump between the 2 wires in the passenger kick panel, turn the key to ACC but not all the way on, and the CEL is gone. I tested this before and turning the car off turns the CEL off until the car starts hesitating pretty bad when I'm driving it again and the CEL turns back on, then it will drive fine.

How can I find out what that code is?? It's not there when I go to start the car or read the CEL!

 

try keeping the plug jumped while you drive and when the CEL does come back on, the light will flash a certain amount of times to read the code.

do you know how to read the CEL? if not: long flash = 10 and short flash = 1. so two long flashes and one short would be a code 21 (just an example).

 

or you can go to your local auto parts place, autozone or advance auto and thy'll read your codes for free.

 

Or simply do not turn off the car while the CEL is lit. Pull the codes then. Even easier.

 

Alright was finally able to read the code and its pulling up Code 43 which is fuel supply system. After some careful googling, it seems my O2 sensor went bad. I guess out of the 3 different possibilities for that CEL, 2 of them head towards a bad O2 sensor.

 

Not true for OBD1.

 

Generally, there is a fuel system problem when you have a performance problem with code 43. Have you replaced the fuel filter and checked for clogged fuel injectors?

 

43 can be caused by a fuel system problem (usually the filter) but it's also (and more commonly, from what I've read) caused by a slightly malfunctioning O2 sensor.

Regardless, I'd replace the filter first. Chances are it needs to be replaced anyway, and they're a hell of a lot cheaper than an O2 sensor.

 

My thought is if it were the fuel filter or fuel injectors, the problem would be prevalent ALL the time, not just sometimes. Also, the fact that it runs perfectly fine after it stumbles then throws a check engine light tells me its an electrical problem (O2 sensor). I'll check the fuel filter but I'm leaning towards the O2.

 

Not sure what leads you to these^ flawed conclusions.

 

Please explain. To me, it doesn't make sense that once the CEL comes on, the car runs perfect. It's like a light switch with how good it runs after the CEL comes on. Does the car somehow bypass the fuel filter or anything fuel related when the CEL turns on? I doubt it.

 

You view problems simplistically in black or white whereas in reality they exist in a variety of shades of gray. This is often true for both mechanical and electrical problems. All symptoms you claim to point to an electrical problem can also apply to mechanical problems. Furthermore, both types of problems can also be intermittent. To think otherwise may lead you down the wrong path.

 

id say its o2 sensor i had this same problem when i first got my 98 civic converted to obd1 turned out the wires to the o2 sensor had somehow gotten stripped and was shorting out on one another id did all kinds of crazy **** like not wanting to take fuel poor idling running rich and then supper lean
more than likely whats happening is its going from closed loop to open loop when the light comes on ud be better off to just unplug the o2 sensor and suffer a few less mpgs till u get a new o2 sensor.....

 

if u get an after market one just remember this connect the 2 black wires to the white ones those are heater circuit tie the gray to the green wire and the last is the ground

 

Just as an update to this thread, I bought a new Honda O2 sensor and it cured ALL of my problems. MPG is back, no CEL, no hesitating. I'm 100% sure the one in there got melted because it was a $40 Kragen special.

 

Funny how this was never mentioned. Would explain why you were so stuck on the O2 sensor.

 

I had no idea what a stock O2 sensor looked like to be honest. I wanted to wait until I got the OEM one to compare the 2 and when I got it, it was obvious.