[Solved]Driver side bank sounds like a plunger/thumping

This morning I started the truck, drove to the gas station and all was well. As soon as I put it in park at the pump it started making a low pitched thumping noise that almost sounded like a plunger going up and down at rpm speed (on the driver side bank). I left it running when I went inside to get my sandwich and it was still doing it. I drove the remaining 14 miles to work and it did it all the way there. When I was coming down hill off the gas coasting it got much quieter. When I got to work I parked it and turned it off while I waited for the boss to arrive and open the gate. After letting it sit for a minute and restarting the noise was gone, but it slowly got back to its original volume as I drove around back. It really almost sounds like a plunger moving up and down at rpm speed, not metal to metal, and it’s definitely different than the high pitch tick cam noise that’s always present. Gonna post the video after this because it’s too big to attach. Please help I have no idea.

 

Zachary, on my end after download, it appears to be a picture only not audio/video ?

 

https://youtube.com/shorts/r5DsHr27jR0?si=KyTg672GADZWZH9h
here you go
You can hear it better if you put your ear up to the speaker

 

Loose vacuum hose. I don't see it at this very moment but that's absolutely what it is.

 

Update: Started truck to go home from work and it sounded normal as usual. Got about halfway down the road and a CEL popped up. So I stopped at the next gas station and checked it with my scanner I keep in the toolbox. P0155 bank 2 sensor 1, the noise also started again about this time as I was cruising 60mph. I’ve had the code for this sensor before and I replaced it but there was no noise and the light went away right after. I kinda checked the vacuum hoses like shifty said and they all seem ok, I don’t feel any exhaust leak putting my hand around the manifold. After sitting at the gas station and checking it I started back up and the noise was gone but came back within a minute of idling. I also cleared the code and it came back as soon as I pulled out of the lot. It changes with rpm but not exactly like an exhaust leak would. Coasting and medium throttle seem to quiet it down. Still not a metal to metal sound.

 

It sounds like a sucking noise to me. Like, loose spark plug, vacuum leak, hose to the intake manifold detached, hose between booster and manifold. Maybe the camera is distorting the sound.

If you choose to replace the O2 sensor, replace both sensors on that bank. Only use Denso sensors for the replacement, and DO NOT buy them on scAmazon/fleaBay.

 

In fact, it sounds almost identical to this sound diagnosed a couple weeks ago: https://www.tundras.com/threads/weird-engine-noise.127280/#post-3249737

 

https://youtube.com/shorts/JWvG-MVCins?si=j7FKPoaPo_FxnfDX
here’s another video i took at the gas station

 

It's literally the same f'n connector from the other thread I just linked, dude.

And your hose is dry/cracked, you need to cut it back.

 

This is the connector that's off. And I circled the crack. And this may be what's causing your P0155, so run for another 40-50 miles after disconnecting the neg batt cable for 10 minutes to clear out everything. This hose is disconnected but you don't see it until you're standing over it.

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It almost looks like the bib is cracked off?

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And here's another shot from the last second of your 1st video. Just in case you're not convinced

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I had several dry and cracked engine hoses. The stealership sells most of them but one of the hoses was like $70. Can’t really find them elsewhere. Would be nice if someone figured out OEM supplier and part numbers

 

You guys are awesome, thanks a bunch. Cut the dry end off, re-hooked up the hose and put a zip tie on it temporarily until I can go get some new hose tomorrow. Started up and both CEL and noise went away immediately. I don’t know how I didn’t see it dangling before. It was a hell of a noise to hear at 5:30 on Monday morning!

 

I had that same hose pop off a few months back. Put back on with a zip tie as you did and good to go. I heard that it had fallen off before I got any codes though.

 

Then it was the same as mine did, fell off on the way to work but the code didn’t pop until the way home.

 

New problem: All the vac leaks and dry rotted hoses were replaced. Replaced o2 sensor per P0155, have cleared the code 3-4 times and drove to work but it keeps coming back. Any suggestions?

 

Which exact O2 sensor(s) did you replace, please list all locations?
What brand of sensor did you buy?
Where did you buy that sensor?

 

Replaced upstream driver side sensor with denso brand I bought at advance

 

Weird, I couldn’t find Denso at Advance when I looked last but glad they got you one. Hopefully they keep carrying them, I’m sure I’ll lose another before too long!

I see two mistakes though.

p0155 is bank 2 sensor 1 (passenger upstream)

its recommended (realistically) to replace upstream and downstream on the bank with a failure to avoid weird discrepancies with having one new and one old sensor.

If www.densoautoparts.com parts finder shows the upstream sensor parts for your truck are the same, you could just swap the sensor you pulled into the passenger upstream. Some years used different parts between upstream or downstream depending on the bank, so you need to confirm.

 

P0155 for an 02 is passenger side (bank 2) upstream.

 

Seeing Bubba’s reply just reminded me also: What Denso part number did you get? Just want to confirm; I know they make a universal sensor, and an exact fit sensor for our trucks. I don’t know (without looking) if both are heated or not, and that code is referencing heat circuit failure. We should check your part number to confirm!

 

Here you go
234-4169

 

Good news is, Upstream are identical on the '02 Limited 4.7L and downstream for your 4WD are the same downstream on both banks also, it's the same part number except the last 4 digits are "-4162". I feel bad for the 2WD guys who have different downstream sensors bank-to-bank on your year/engine/trim!

Hopefully you still have the old sensor, you didn't toss it or mangle it pulling it out? If so, slap it in the passenger side upstream slot and see if your code disappears.

 

Yep, y’all were right. Replaced the passenger side upstream after fighting the old one out for an hour. No codes after a 30 min drive.

 

Sometimes readiness takes a couple of trips, so don’t count your chickens yet.

and if the code changes to (p013x, I think?) or to cat efficiency, holler back. There’s a reason why, and it’ll make sense when explained. (It won’t actually be your cats)