Rep Power: 182

As few of you may know, I had a rod bearing knock in my old engine and I decided that swapping the engine with another used engine was the most
cost effective way of solving the problem.

And it has been done.

After many days of hard work, it is completed.
However, there's really something weird about it, the problem itself.
Now the there is no more obvious-easy-to-notice knocking that occurs
between 2k-3k rpm when blipping/feather the throttle.

But the engine itself isn't 100% quiet and smooth as I would have expected.
This may sound really weird, but I feel that, as I drive it more and more,
the engine is beginning to act like the old engine more and more.
How is that possible? It isn't rebuild, it is a totally different engine.

The only thing that are the same are the sensors, I've transferred most of them from the old engine to the "new" one since all of them seemed to have been working in good order.
Here's the list of sensors transferred: TDC, CKS (Crank Position Sensor), Knock sensor, EGR sensor, the throttle body along with all the sensors on it such as TPS, EVAP purge and IACV.

When I first started the engine, there was some noise, a slight knock when I rev a lil bit the engine (2k rpm). But it warmed up and the engine was correctly lubricated, no more noise. Even now on cold start, it's almost silent.

The engine itself seems to be running okay, no loud knocking, running with lil' bit more power. However, when I push it a little bit harder (3k rpm), the same way I would with the old engine, the engine seems to be struggling and working really hard, there's lots of engine noise and vibration at the exact same RPMs like the old engine.

Even when free revving (no load), it vibrates the same way and at the same rpm. It's like the engine or the ECU is duplicating the old engine behavior on the new engine O_O.
I also feel like it's getting worse: more noisy and more vibration and little bit of knocking starting to be more obvious, less responsive and less powerful than at the beginning.

I've been suspecting the knock sensor, but there's no Check Engine Light or code stored related to that. I know KS are supposed to control the ignition timing and it could be responsible for knocking and power issue.

I still have the sensors from the engine bought though, could swap them if I wanted to.

Any advice, experience or opinion on this guys?

Thanks

 
Rep Power: 186

See below thread. It may or may not pertain to your issue you're hearing.

https://www.civicforums.com/forums/3...rod-knock.html

 
Rep Power: 182

Yeah, well the old engine did that, but much louder and noticeable.

The one I swapped does a little little bit, almost not noticeable.
But it's noisy in other ways

Here's how my old engine sounded:

 
Rep Power: 517

A knock sensor cannot cause a knock.

What's the new used engine sound like?

 
Rep Power: 182

What about a defective knock sensor?

Video might be coming soon for the new engine sound.

Feels like the problem is independent from the engine itself
Knock was indeed there in the old engine.
New engine isn't great either.

 
Rep Power: 517

Again:

Nor can it prevent a knock.

Maybe I don't understand what you are trying to ask?

 
Rep Power: 192

These engines aren't exactly known for being quiet.

 
Rep Power: 182

Well, my understanding of a knock sensor function and purpose was that it is supposed to detect knock in the combustion chambers due to low-octane fuel and send a signal to the ECU in order to retard or advance the timing to prevent knock from occurring in the engine.

My point of view is that if a knock sensor isn't working properly but not necessarily broken was that it would not knock prevent knock from occurring by sending wrong information to the ECU.

Perhaps I'm thinking a bit too far since I don't have any CEL related to that and that the engine seems to be running correctly.

To sum up the new engine behaviour, it doesn't knock anymore, at least not as loud as the other one, but still takes a lot of time to rev even in 2nd and 3rd gear.
Also, I still can hear some kind of knock at high rpm, although I don't know what part of the engine is causing that noise.

One more thing, I've transferred my old sensors from the old engine such as the CPS (Crank Position Sensor) to the new engine.
I've read about CPS relearn procedure. do I need to do that?
It's still the same sensor and the same ECU.
If I were to put the sensor from the new engine when it came with it, do I actually need to do that relearn procedure, or does it only apply to brand knew unused CPS ?

 
Rep Power: 517

Only for combustion related conditions. That would be within the combustion chambers and the only control possible is to retard ignition timing until the knock subsides.

Maybe I wasn't clear in that earlier post:
Mechanical and physical problems cannot be controlled by any PCM.
It may detect noise and attempt to retard ignition timing as it was designed to do though, but without any effect upon the actual problem because it is not a combustion problem.

Make any sense yet?

Probably. Knock sensors on Hondas seem to be pretty dang reliable.


It's CKP. CranKshaft Position sensor. OBD2 standardized terminology.
No learning required on that engine. 7th gens are plug and play. (8th gen and newer need a learning procedure.)

Can't really help from here. Sounds like back to basics.
If you THINK it could be caused by the knocking, unplug the knock sensor so it can't retard timing and see how it runs.

 
Rep Power: 182

Mechanical and physical problems cannot be controlled by any PCM.
I'm well aware of that.
Maybe I'm being too superstitious, I thought that by putting a sensor from a defective engine, that same sensor itself, that has been exposed and in interaction with a defective engine, it would try to duplicate the same behaviour from the old engine because it has been used to it.

I guess I'm being too irrational about this.

It's CKP
Oh yeah, sorry about that
I thought I saw this somewhere:
CPS for Crank Position Sensor
I used to use the old acronym.

About the engine power itself.
Maybe I'm expecting too much from a used 1.7L 4 cylinder engine.
When I test drove some of them, power didn't seem to differ much from my engine. One thing I can be sure of is that the power output and noise is much smoother and quieter, as opposed to mine.

That same roughness and irregularity at specific RPM from the old engine is present in the new engine at the same RPM in the same way. That's why I'm bugged LOL

 
Rep Power: 517

Um, no.
It is nothing but a microphone, a listening device.
It cannot learn, it cannot think on its own.
It does not care what it is attached to, all it can do is listen.

More like overthinking.

I get that way when I have to fill out a form or take a test. It's horrible for me, and my GF just doesn't get it.
And I thought tax forms looked simple. How wrong I was.

These engines aren't like a hand-built hot rod. They are mass produced and should all be damn similar in performance as long as nothing has been butchered.

Restricted exhaust or intake?
You never posted a new video?

 
Rep Power: 182

Um, no.
It is nothing but a microphone, a listening device.
It cannot learn, it cannot think on its own.
It does not care what it is attached to, all it can do is listen.
Yeah.
A sensor it just that.
But, how about an ECU?
Being a more sophisticated device.
Does it have keep trace of some data in its memory even after you reset it?

Restricted exhaust or intake?
I know exhaust flow can be restricted due to the catalytic converter.
But an intake can be too?
How?

You never posted a new video?
I know, sorry for my laziness
It's kinda of a hassle too since I need to install my tri-pod,
record, load it in the computer, convert it and upload it.

 
Rep Power: 517

No.
It only has a basic ignition timing map modified by KS input, no memory or adaptive technology for timing controls.
I once had a turbo car with a complaint of "can't rev up" wouldn't go past 2000 RPM.......Air breather box was completely loaded full with dog food. Mice.

Just an example.

ANY restriction on either end, intake or exhaust, would cause a loss of performance. Right?