what to do...

[Edgefevah]

[/URL][/IMG]


I am getting this sound at idle, I havent been able to pin point it quite yet and was hoping some skilled veterans of the 4.0 could point me in the right direction.

The truck idles at 950rpm and the sound is sporadic. The motor is currently running 5w40 sythetic Chevron oil, at least that is what the previous owner was using and i havent had to change the oil just yet. The idle is rough, shifter stick wobbles more then it should and you can feel it when sitting at a light.

I had an engine in the truck before that had the ticking sound so I am quite certain it isnt rocker arm wear. I just replaced both the LIM gaskets and the upper as well as the valve cover. brand new PCV valve.

ANY opinions would be appreciated.

 

[Edgefevah]

This is a video, click on it to listen any issues let me know. Couldn't load the audio file onto photobucket so I just recorded it off my computer.

 

[RonD]

Couldn't hear anything but if there is a ticking like noise it could be the injectors, they can be noisy.
Get a longer small hose and with engine running put one end at your ear and the other end at each injector, see if they are the source of the ticking.
They aren't broken just noisy

And clean the MAF sensor, it's a common issue that causes rough idles and missing, and easy to clean just to see if that's the issue.
http://www.therangerstation.com/tech_library/CleanMAF.html


Also if you are new to the 4.0l, always use motorcraft spark plugs, the 4.0l eats other brands.

If you have a lot of play in the shifter look here:
http://www.therangerstation.com/Magazine/winter2007/shifterbushings.htm

 

[Edgefevah]

Most of the knocking sound happens in the first 10 seconds of the video. The rest of the video is just showing how it dissipates when I rev the engine up around 1750-2000rpm.

I have cleaned the MAF sensor with the appropriate cleaner, It has new motorcraft plugs. as for the shifter i wasnt aware you could still get parts so ill look into it. thanks

 

[RonD]

I can't see a video or hear it.

Knocking is different than tapping.

Oil pressure is lower at idle and even lower when oil heats up and engine is at idle.

Knocking could be a rod bearing going out, loosening up, so it "knocks" each time the cylinder fires when oil pressure is low.

Old trick to test was to pull the spark plug wire on one cylinder at a time, if knock goes away, or gets real quiet, then you found the cylinder and the problem.

Lifter and rocker tapping/knocking issues will still make noise when oil pressure is low, so if it's not the bottom end it must be the top end.

 

[Edgefevah]

well Ill have to try the spark plug test, cause it doesnt always make the knocking sound. which makes me think it is the lifters/rods/rocker arms.
sucks that the video doesnt work. did you try clicking on it?

 

[shane96ranger]

Cranked up my speakers, and can't hear much. Try recording next to the motor maybe?

 

[Edgefevah]

So you were able to listen to the video Shane96 ranger? Ill re record it and see if it turns out better.

 

[shane96ranger]

Yes, the audio was very faint.

 

[Edgefevah]

well, I don't know how to make the audio work any better. but what I can tell you this is that it seems like a bad bearing knock whether it is a "Rod" or "Main" bearing. I had to replace my engine awhile back and replaced my stock engine with a engine froma 95 explorer with EGR. I deleted the EGR and put the motor in, later on I found out that the 95tm cast heads had heart shaped chambers that tend to burn out and engine real quick if the appropriate ECM is not in the vehicle. So I am basically inquiring as to whether or not putting this engine in my 93 ranger without switching computers would cause this? thanks.

 

[RonD]

A quick look at the "95tm cast head" burnout issue, which I hadn't heard of, was in switching a block that came with 90tm to 95tm, and since it would have higher compression but same fuel/air from PCM, would (90tm)pistons be effected.

In general no, not an issue I wouldn't think since you swapped the whole engine.
The PCM might be running a leaner mix than the 95tm head can take, but if you don't have pinging or a hotter running temp gauge then that shouldn't be a concern.

Make sure EGR blocking plate is still good, exhaust leak can sound just like a knock.

 

[Edgefevah]

I switched manifolds instead of using a block off plate. Going to try sea foam this weekend and see if that changes anything. Maybe there is just some carbon build up

 

[Edgefevah]

well I dont know how it happened but I was working in some wiring under the passenger side of the dash today, and found out why my engine was making a tick/knock. Low and behold somehow my vacuum hose that connect to some sort of canister/solenoid inside the cab by the passenger side kick panel had come off. started the truck up and went for a cruise and no more problem!!!!!!!!!

I spent too much time trying to fix this problem lol.