acmeotally

I have searched and searched i thought i found the problem but then it came back.

i have a 97 civic lx 1.6non vtec. When i first start it up and accel in usually first second and third it bogs down unless i put it wot then it revs up. after it does it one time it doesnt do it again until i shut it off and let it sit.

I replaced the distributor and fuel filter. I dont have a cel on. The thing i dont understand is it only does it when i first run it. I was thinking maybe a tps but im sick of parts changing.
any help would be great thanks.

rick_rabies

i would say tps or speed sensor. do you have a obd2 to 1 conversion with an obd1 ecu? jus wondering. your car being googy without cel is tuff to fix but 1 part at a time...or get a new motor

acmeotally

haha I have a obd2 motor I would get a new obd1 motor but I live in mass and it would not pass emissions. The cel not coming on annoys me because it would definitely help point me in a direction. But i never thought of the vss thanks.

acmeotally

I changed the plugs and wires and its still doing it. Could the iacv make it drive differently? I thought it usually only effected it when idling.

rick_rabies

yes. did you ever bleed the coolant? take off the iacv and clean it with brake cleaner and some cutips

ej8ster96

check o2 sensors, still take the car to advanced and see if the computer threw a code and the cel didnt come on, but it sounds like 2 sensor, i had that problem for a while, well right now i still am, but my car doesnt shut off

acmeotally

I checked the codes still none. I cleaned the iacv and replaced the pcv valve. It still does it.

Is it possible to have a bad o2 sensor without have a cel on? I still havent tried bleeding the coolant.

Also I have a small leak in the exhaust in front of the second o2 sensor could that give the sensor a false reading?

ej8ster96

yes, it is the second o2 sensor, im havin that problem with my civic and my ranger, try replacing it

acmeotally

ok i havent tried replacing the o2 sensor yet because it was only happening at start up and i thought the ecu doesnt read o2 at start up.

recently i got a p0113 iat sensor high. the car also runs rough now and hardly idles sometimes stalls. I replaced the sensor and it still does it but the cel hasnt turned back on. any suggestions?

rick_rabies

..did you bleed the coolant

acmeotally

i just blead the coolant and i unhooked the battery for a little to see if maybe if the ecu reset it would do something but nothing.

I unhooked the tps and it didnt really change the idle. Does cleaning the iacv usually always work or could i just need a new one.

rick_rabies

that could be it. how old is it? this should be about where Ronj@ht comes in and gives the magic answer you need

acmeotally

idk how old probably original. I noticed when i unplugged the map sensor and started it is idle good when i plug it in it idles like ****. My friend has an extra civic so im going to try another map sensor if that doesnt work ill try the iacv and let you guys know

Former User

Sorry, I don't have any magic answers, but I would also do the unplug test for the primary O2 sensor and the 2-wire ECT sensor under the distributor to see if you have the same outcome as unplugging the MAP sensor.

acmeotally

I swapped a throttle body from a honda my friend had with his tps iacv and map and it ran the same.

I let the car sit for the day and took the fuel line off the rail to see if it was holding pressure and a little gas just dribbled out didnt really spray or seem to have much pressure is this normal?

Former User

This is probably normal. Turn the key to ON(II) to let the fuel pump prime and then repeat your test.

acmeotally

I did it with the key on it sprayed a little the dribble, which i expect is normal.

ronj@ht: If it does it when i first start it and drive it could it be an o2 sensor because I always thought it doent look at them at all until it is warmed up. Also I will try another ect sensor and see what happens

Former User

Your fuel pressure may be low, so it might be worth hooking up a gauge to measure the pressure.

You are right about the O2 sensor not kicking in until the engine reaches operating temperature. As you said, checking whether unplugging the ECT improves the condition is worthwhile.

Have you pulled off the distributor cap to inspect the cap and rotor contact points and the general condition of the distributor internals?

acmeotally

yes I have replaced the whole distributor what should avg fuel pressure be under normal accel

Former User

acmeotally

Thanks for the fuel diag info. i took your advice and unplugged the ect sensor and it ran fine didnt bog once. But im worried it might come back. Is it ok to drive it for a whole day with unplugged to make sure it doesnt do it?

94_DC

Are you sure the plugs are connected to the right thing? Try "mismatching" them and see what happens, same thing happened to someone I know.

Former User

With the engine (off) cold versus hot, what resistance do you measure across the two terminals of the disconnected ECT sensor? This test of course requires a multimeter.

acmeotally

about 1 kilo ohm

Former User

It's important to know whether the engine was hot, warm, or stone cold for this measurement. The reading you posted would be normal when the coolant temperature is about 104F. A completely hot engine should be about 200F. A stone cold engine should be less than 104F, depending on the outside temperature and whether the car is in the sun or shade.