ezone

I'd expect a loose belt to make a loud screech noise upon start up.

Is the belt original length, still turning the compressor pulley? Pulley bearing going bad? (I'd expect to hear rumble noises)

contevo

yea does screeching noise I guess I didn't tighten it enough when I was putting everything back when I did timing belt. I'm going work on this tomorrow to fix it. I just drove back home from work which is 17miles at 70mph @ 3k rpm no stuttering this really has me puzzle, and also forgot to mention I have crack on manifold which I read is very common on this car is not big crack but you hear like fart when you accelerating at low speed all this crap happen last week right after I did my inspection like I mention before, got lucky lol I do have plan buying cat but not right this second those damn thing are expensive.

contevo

So I have change air filter and recheck coil,and plugs and added some fuel injector cleaner, and today I check the transmission fluid this is the result



No new engine code beside p0420
So hardfigure out wtf is it cause does it randomly like other night me and my girl went out I was doing 70+ and did the jerking even my girl was like wtf was that, and did it again on our way back home I was doing 80, and didn't do it today while I was doing 60mph

ezone

Got a scanner that will let you see live operating data?

contevo

I bought a obd11 Bluetooth dongle so I can use the on my phone with torque didn't work for me I sent it back. I'm going check fuel pump it self or replace but the symptoms I read doesn't really match mines

ezone

No scanner huh.......
I can't feel it myself so I'll take a few guesses

Unplug both O2 sensors and give it a drive. See if the symptom changes.


ATF looks a bit on the dark side too.

contevo

OK.
The atf like said before idk when was last time previous owners changed it. so when I do change it I'll do another check on it if still looks like that I'm screwed, this car was given to me by a friend when I first move down to Texas, I can't be picky when is free lol and also he didn't know much about the car either. all we know from the vin is, the car had 4 owners.

ezone

The fluid will still be darkish after you change the fluid.
The trans holds about 8 quarts, but you can only drain out about 2.5 quarts so when you pour 2.5 new quarts in it will mix with 5.5 quarts of older dark looking fluid.


Color of the trans fluid does not automatically mean the trans is bad or has problems.

It should do unexpected and obviously wrong things if there's a real problem.

contevo

Ahh.. I was going to empty it and replace with Honda fluid who know what they use on this car, I hope Hondas fluid and services manual i download it from here didn't mention it. So I unplugged both o2 sensor and drove the car like mad man on the parking lot than i got on road by my apt the speed limt is 45 I did 50 on it up an down the car felt different faster or just messing with my head, didn't jerk/stutter she idling normal and no roughness which she does with sensor on anyways but like said I felt a different

ezone

Hondas ATF is now called DW-1.

Hmmm. If unplugging the sensors makes the symptom go away, that's a clue they (or at least one of them) may be a problem.

If you think it helped, drive it to work or whatever your normal routine is and see if it really does get rid of the symptom.

Then reconnect the lower or secondary sensor and repeat the same drive routine test.

Then reconnect the primary sensor and see if the symptom returns

contevo

OK, running without this sensor would it damage my engine?

ezone

After disconnecting the sensors I should have added: disconnect the battery for several minutes so the computer can forget its learned fuel trim values.
Then drive it.

Disabling the sensor and letting it "dump memory" will cause the computer to revert back to its basic fuel injection quantity table and operate without any correction factor from O2 sensor input.

No, it won't hurt the engine.
Yes it will set more codes, you can ignore for the moment.


-----

If you had a scanner that can display the sensor values in real time, you could watch and see if the front O2 sensor reading gets stuck at the same time your engine is bucking, along with the fuel trim value maxxing out.


--------

There could be other causes for your symptom, but I thought of this one first so I'm running with it LOL

contevo

OK ill do this test tomorrow. I have feeling is downstream sensor cause my engine light would stay off for long time than come on with p0420 and randomly turn off and sometimes goes weeks or months without coming on that why I was able pass my inspection this time around lol , than 3 days later after inspection I was driving I got the jerk light came on as been on since.

ezone

I think the front sensor would cause the problems.

contevo

So here the update, I reset the ecu and left the o2 sensors unplugged drove the car about 60 miles in total today, different speed ranging from 60 to 90mph and it was bit hot day around 7pm, no jerking and honestly my car feel a lot different and more responsive than before.
but I'm going to drive it again without the sensors for another day just to make sure than I'll plug in one the sensors on my way back from tomorrow.

alex_nyc

This is good stuff guys!!

contevo

OK here another update so I was accelerating above 60 today, I got the jerk and is hot day today this is first time since I unpluggled the sensor, and I'm assuming the low rpm coming to a stop at red light because the sensor? And doesn't do it when I put the car on park.

contevo

Oops double post

ezone

IDK. Are both sensors unplugged right now?

Got a working scanner yet?
Again, IDK. Might need to do an idle learn since the battery was disconnected, but that might be pointless to do right now because of unplugged O2 sensors.

contevo

yea the sensors are unplugged
I'm really thinking im going have to replace cat along with sensors because
has to be the problem, I also read when cat is dying or already gone can cause random jerking etc... and also the crack on on the manifold might have gotten bigger too letting air in, if I buy new sensors and cat is crapped out is going mess up the sensor again...
I'm hopping I get my bonus soon so I can buy all this at once.

but like being saying before the car performance different on hot days than cooler days.

ezone

No clue on the temperature difference.
Is the difference very minor?
Running the AC will put a big load on the engine, you can definitely feel the compressor cycle on and off as you drive..

alex_nyc

IMO -dont change them unless you can prove they are bad!! thats a lot of $$$ to spend and you still have the problems!

fix the crack first! -maybe put some RTV over the crack as a quick fix to test??

ezone

^yes this. (this thread is so darn long I didn't remember a crack being mentioned until his last post.)
A crack can let air leak in and screw with the accuracy of the sensor(s), therefore screw with fuel injection calculations by the computer.

but I'd think ordinary RTV would burn away as soon as the manifold heats up the first time. The manifold can reach 1000+ degrees.
Braze it?
Where exactly is the crack or leak? (in the middle right at the sensor hole?)

contevo

sorry for late respond I have been busy with work.
the crack looks like this:
"BLUE MAGIC 18022K Crack Repair Kit,High Temp,Dark Gray"
I try to patch it up with this few months ago but I probably didn't do it right...

contevo

so here an update. My alternator when out on me I can't complain lasted 14 years, and i replace o2 sensor upstream and jerking has stop hasn't done it yet since i replace both of this parts, I still have CEL light on and is for p0421 so my cat is next im going to replace, and along with ignition coil and I want to do the ATF change but i'm actually bit scare of doing it i read few post people change their ATF fluild has been long time between changes sometimes open pandora box sort of speak lol.

mikey1

its just as simple as doing an oil change really,

just drain and fill and make sure you use honda OEM fluid only,

before you drain make sure you have a long enough funnel to reach the tranny dip stick/fill point,

fill slowly and keep checking.....DO NOT OVERFILL !!

contevo

So been a while lol. here is an update
So last month i bought new cat-converter and two ngk o2 sensor, and the car hasnt jerk since. I also clean the throttle body following a guide on here. So recently im experiencing next day cold start up rpm start up normally than few seconds later goes to close to 2k rpm than goes back to where left off than idle normals after few mins than yesterday a cold start up rpm goes up to close 2k rpm than drop almost turning off than goes back to idling than idle normal after warms up, and did it to me today again so right now im doing relearm idle... So what's going on?

mac25

Check your throttle body for loose connections (throttle position sensor and what not) and loose vac lines.