Stupid jerking @ 1800 again

[talonmike]

I had the 1800 rpm jerking a year ago. I fix it replacing o2 sensor. Before o2 I replaced every thing without any success.

Now it start jerking again

I installed

- 3 new plugs.
- 3 new coils.
- injectors replaced 4 years ago.
- I supect my EGR that is about 1 year old. So I try to install the one jeff repair for me. Same problem.
- I bought a new EGR from honda. Same problem!

I really don't know where to search now. I think that I will try my spare Throttle body.

Could it be the front o2 again?

I am sick of this insight that always jerking now!

[bryankwalton]

Have you cleaned your EGR plate?

[talonmike]

Originally Posted by bryankwalton

Have you cleaned your EGR plate?

Yes, I forgot to mention. 6 months ago. It was already cleaned.

Could it be the map sensor?

[eq1]

I seem to recall a thread where the poster tried various things to get rid of the low rpm jerking and it was the catalytic converter - it may have been suggested that EGR, O2 sensor, and catalytic converter problems are conceptually linked and can cause the same jerking symptoms...

[talonmike]

I have only 100kmiles, you think that it could be the cats?


A clogged cat should not give problems at only 1800rpms?

[eq1]

I don't have any direct experience - just recall reading something here about the low rpm jerking issue and the cat or cats... I doubt you'd be able to find it in a search, as there's so many threads about 'jerking' and 'bucking' and what not. Maybe someone else will chime-in...

My own take on low rpm jerking is that it seems to have something to do with the management of the transition/s between lean burn mode and non-lean burn mode, and electric assist (do CVT cars get the jerking?)... For example: at low rpms, such as between 1000 and maybe 1600, you've got very little gas engine power. If you're light on the throttle you get lean burn, if you need more power the car can either drop out of lean burn and/or give you electric assist. In my experience it seems like, for whatever reason, sometimes the car can't make up its mind - drop out of lean burn, stay in lean burn and add electric assist, drop out of lean burn AND add electric assist, etc... I imagine there's a lot of sensor type stuff that helps the car make its decision, such as the EGR sensor/reading, maybe the O2 sensor/reading, MAP sensor, etc etc. So, if one of these things is off you might get problems like jerking... I don't know, there's a lot of different jerking and bucking issues...

So where does the catalytic converter fit into all this? Not sure. I seem to recall that a faulty cat can affect the O2 sensor readings and/or the EGR behavior, and we know that a dirty EGR valve or worn sensor can cause low rpm jerking/bucking... Whether a 100k mile cat can be bad, I don't know. It would depend in part on what kind of environment it's been subjected to, like a wet salty one, where corrosion might be an issue, or maybe something like bad gas or additives that do something to the special metals in the cat? Maybe there's a quick and easy way to test the cat?

[talonmike]

I also forgot to mention that when the engine is cold, it is working perfectly. So I also change the coolant sensor in case. Like you say, is start jerking only in lean mode.

I will try my other Throttle body, but I doubt it will fix that problem. Maybe the TPS is intermittent.

Thanks for replying eq1

[jime]

Originally Posted by talonmike

I have only 100kmiles, you think that it could be the cats?


A clogged cat should not give problems at only 1800rpms?

I had one replaced by Honda on warranty at only 80,000 miles, so it does happen. I'd tinker a lot before I went to that extreme, assuming you are out of warranty

I think the car usually generates ECL codes when the cat fails. Others may differ. I got codes when my cat failed.

[talonmike]

I have no codes

[spets]

If the cats are clogged, they can cause issues with the jerking.

Does the jerking go away if you unplug the EGR valve?