Engine trouble after timing belt repair

I bought my brothers car from him 3 weeks ago, 2002 Hyandai Santa Fe, and had the timing belt changed the same day I made the purchase at 157,000miles. After the timing belt change my brother said the car sounded different but there was nothing obviously wrong. 1 week after there was a loud engine noise that went away on its own. Now, 5 days ago the check engine light came on and 2 days ago the engine created a very loud whrring noise that was obviously very wrong! I popped the hood, checked fluids, and it wasn’t overheating, I took a video of the noise and then drove it into the dealership. The noise had stopped by then and luckily I had the video of the noise. They performed 1 hr diagnostics and stated its either the valve train (in which the engine would have to be replaced $2-$3000) or buckets (what are these) which will cost $600. They need 3 more hours for diagnostics,
They said it has nothing to do with the timing belt replacement - do you agree? Why else would this happen?

Impossible to say for sure remotely.

The timing belt does have an idler pulley that, when it isn’t installed correctly, allows the timing belt to flop around and possibly skip teeth.
One would imagine that, if that is allowed to happen, it will do major valve damage - at best it would cause your engine to run really badly, if it was running at all.

Buckets? Never heard of that in that context.

Perhaps buy a cheap automotive stethoscope (10 bucks are harbor freight) and probe around if you can hear where the noise is coming from.

I’m kinda hard to accept that the timing belt slipped a tooth. They don’t slip and then fix themselves. Once they slip…it stays slipped until someone fixes it. And if this is an interference engine…then a timing belt slipping can easily cause valve damage.

There’s a lot to pull of just to get to the timing belt. I suspect the timing belt change is the culprit…but not convinced it’s the timing belt itself.

You need to get the codes (DTCs) read and post the actual code here (P0xxx format). Then post that video.

Buckets are the cam followers if you have directly actuated valves, common on DOHC engines. There are shims inside the buckets that are used for the valve lash adjustment. That noise would not go away. The dealer could have pulled the top belt cover off the check the belt tension and timing in a few minutes and that should have been part of the diagnostics.

Is this dealer also the one who did the timing belt replacement? If so, go to an independent mechanic and have the timing belt tension and timing checked. Should not be more than an hour labor to check, and if it is off, you should be able to recoup the cost from the dealer, if he is at all honest. If not, call your local TV consumer investigator reporter.

If it is the valve train, that could be caused by a mistimed timing belt, that is why you need an independent mechanic to verify and document this.

If it is running good now, the dealer may have reset the timing belt alignment and set the tensioner correctly during the “diagnostics” in the hopes that the sounds don’t return and that permanent damage wasn’t done, or at least won’t show up for a few thousand miles, that is if they are the ones who did the belt in the first place.

I vote they didn’t adjust a tensioner correctly–related to the timing belt change. RemcoW is probably right. Have prove it out yourself, or have another shop do it. Get the belt taught and tensioned correctly and you should be fine. If not, move on to the next problem.

Here is the video. The dealer has the vehicle and they are the same who did the timing belt and the current diagnostics. My brother had used them for the past three years with good success.
I have posted the video, i hope it works. Thank you for your replies.

That does sound like excessive valve lash, but I would not expect it to come and go. If your engine has hydraulic lifters, also sometimes called buckets, then it could be a bad lifter or lifters, not related to the timing belt change. Ask the dealer if it has hydraulic lifters. Unlike solid lifters, bad hydraulic lifter noise can come and go.

Definitely excessive valve lash

The manuals shows the smaller engine option uses hydraulic lifters and the larger displacement uses bucket lifters. Which engine do you have?

Probably should have added that since it’s coming and going it’s likely a failing hydraulic lash adjuster or worse; iffy oil pressure.

I have the larger engine 2.7L V6

The timing belts on the 2.7 are pretty easy and straight-forward to do, hard to screw up the installation on these. Also, if the noise comes and goes I don’t believe it’s the timing belt. The sound in the video to me sounds like valve train noise.

At 157,000 miles this should be the second timing belt replacement on this car, right? If not, and this maintenance has been deferred this long, was the oil changed every 5000 miles? Perhaps theres some sludge buildup in the engine causing this noise.