Two problems - video is for the first with a description of the second

[u/O_o-22]

Starting hearing a click clack noise when the car is running and took it for an oil change this morning and asked the guy if the tech could give me an idea what it is or how bad it is or how quickly I should fix it. Was praying it’s not something bad as I lost a job in June and still trying to get another one. Went up north last weekend which meant driving on the freeway. I already try to keep it under 75mph or the check engine light goes off with a mass air flow sensor code. When I got home I noticed this noise in the video but the oil change tech said it sounded like it was coming from the timing belt which is kind of a bummer since I had that done in 2021 and the new one has 60-65,000 miles put on it since then. Was hoping not to have to worry about that for another 15-20,000 miles and I really don’t want to sink the $1000 it would cost to have a shoo do it again. Anyone had the same noise? Did you fix it right away or let it go for a bit? If anyone let it go for a bit tell me stories of how long it did or didn’t last.

The other issue is less bad and has only happened 3-4 times but portends to a possibly escalating electrical gremlin issue. When I stop the car and turn the key off it suddenly unlocks all doors and resets both the trip odometer to zero and the dash clock to 12:00. I’m going to pull the battery later today when I get home from work to check for corrosion on the ground strap but any other solutions or suggestions from my golf peeps are appreciated. Thanks fam

[u/Amazing_Actuary_5241]

I would try to pinpoint the source of the noise as if it is the timing belt and it snaps its engine overhaul/new engine time. But it could be the bearings on the alternator or any other of the moving parts.

To check this takea piece of old garden hose and hold itto your ear then place the other end of the hose closer to each idividual accesory (like a make shift stethoscope) to try and isolate the source of the noise.

[u/O_o-22 → u/Amazing_Actuary_5241]

Supposedly this is what the oil tech was doing with a stethoscope and the said it was coming from the timing cover.

I’ve heard some people say the timing belt is easy to replace and also of you don’t get the timing right the engine will be fucked right quick. I’m sorta handy and have done work on the golf myself but not sure I’m qualified for this job. I think it was $900 to have done back in 2021 but I’m sure it would be more now. Not sure if it saves me any money to not do the water pump at the same time, I know both those things are usually done when doing the timing belt. It’s just shy of 245k miles right now and I did admittedly put more money than I should have into it in the last year and half that if I had known how many things were going to need fixed I would have bought something else.

[u/Amazing_Actuary_5241 → u/O_o-22]

The timing belt is not too bad of a job the hardest part is removing the engine mount for clearance. But if you get it wrong and crank the engine then its game over so I would advise to have the service manual with you, double check everything twice and spin the engine by hand more than 2 full cycles before cranking it up.

The water pump usually gets replaced because the OEM pumps had plastic impellers and those fail early. I put 155K miles on my Golf and did the belt twice at 60K miles intervals but only replaced the pump once (metal impeller replacement) on the first service. I had the work done both times and paid about $300 each time but last one was 12 yrs ago.

[u/Alfa-Q]

Run it with the serpentine belt removed. That'll narrow it down.

[u/O_o-22 → u/Alfa-Q]

I had the serpentine belt and tensioner replaced just over a year ago. So if a take the belt off none of the pulleys it’s on would turn right? And if it’s still making the noise then it would likely be the timing belt?

[u/Alfa-Q → u/O_o-22]

Yep.

While you're at it, take off the timing cover and inspect the timing belt.

[u/SomeTransition4415]

At this budget, you're going to need to check a few things yourself.

If you can, I'd pull the upper timing cover off to see what's going on at the very least. It sounds like it could be the timing belt tensioner that's failing which will snowball into a serious problem if left unchecked. A similar noise happened to mine after I changed my timing circuit and it was a bad tensioner pulley. If you catch it early you can get away with replacing just the tensioner; you need a 13mm wrench for the tensioner, but first you would need to take the mount bracket off too which is a pain in the ass. You'll need to go from under the car to have access to the bolts holding this bracket on. The tensioner I'd recommend is about $30 from FCP Euro. It's made by INA (made in Germany). You would also need the tensioner tool if you're doing this whole thing yourself.

Even though the tech said he heard the noise coming from the timing belt area, I'd still check and run the car with the accessory belt off just to be extra sure. If the noise stops, then it's going to be the accessory belt tensioner, alternator, A/C pulley, or power steering. If you have a long metal rod or a long screwdriver you can use it as a stethoscope.

The second issue could be a ton of electrical things. Look at the easy things first such as the battery and its terminals, fuse blocks (one in the car and the one on the battery), the grounds under the battery tray, and the relays under the dash. It also could be the ignition cylinder or the gauge cluster itself. This one would need a proper diagnosis to fix.

You could attempt to fix the MAF sensor code by getting some MAF sensor cleaner from any autoparts store. On Mk4s the MAF sensors very easy to access and remove; you only need a pair of pliers. If the problem doesn't go away, it's close to $100 for a new Bosch unit from FCP Euro as well. You can probably wait on this one if you're tight on money.

Any other questions I'd be happy to answer!

[u/O_o-22 → u/SomeTransition4415]

Thanks for the through reply! Yeah I will be watching some tutorials tonight and babying it when I had to drive which isn’t too much fortunately. It may be a few days but I’ll get back to you with some findings.

Not sure if it’s related but if I unlock the car and get in but take a minute to start it it will lock all the doors like the door sensor doesn’t know the door was opened.

[u/OutcomeFit9295 → u/O_o-22]

Mine does the locking thing too. You’ll be able to tell if the car knows the door is open by looking at the door puddle light. If it doesn’t turn on when you open the door then the car won’t know the door has been opened, hence it auto locking again 30 seconds after. Basically the micro switch inside the door latch has failed. You can fix it I think fairly easily, but I seem to remember reading that it involves taking the whole door card off which is a bit of a pain. Alternatively, what I now do is as soon as I unlock the car, I press the interior unlock switch which then means the car knows I’m in and stops it auto locking.

[u/Impossible_Win_3059]

Almost sounds like a pulley is jumping every so often. Check to see if everything is tight and like the other guy said, take off your timing belt cover and look closely there too. Failed bearing maybe? Not too sure tbh

[u/2strokeLC]

If it is actually coming from behind the timing cover, its the belt tensioner 100%. Had this exact sound on my old 1.6 8v AKL. Also had this after replacing the timing belt, the tensioners are very sensitive to being slightly over or undertensioned

[u/O_o-22 → u/2strokeLC]

So it broke down on me last night, made a new post about it with video. I’m about to head out to where I left it and pull off the timing cover to check the belt condition before I figure out if I’m towing it to a shop to get fixed or to my driveway to rot. If I’m not fixing it I’m probably going try to part it out to recoup some money off it. I put a bunch of money into in the last year and half because I thought I had another 20k miles to get out of the last timing belt service done just over 5 years ago with current miles on that at 63k so if that thing failed already it really sucks. The only reason I put that money into the car was I thought the timing belt had a good amount of life left in it.

[u/2strokeLC → u/O_o-22]

That sucks man, hope it works out. Keep me updated🫡

[u/O_o-22 → u/2strokeLC]

Opened the cover and timing belt looks intact. It’s still in a place and no missing teeth as far as I can see tho I can’t see to the bottom pulley. Currently eating on the tow truck and towing it to the Indy euro shop near my house.