Papez

No 21. 6U0121038 for non-ac 6U0121051F for AC Each is paired to a different pipe no 27, AC version wraps around the oil filter to clear the accessory holder. No 29 appears to be heater matrix output hose, that returns to the #27 pipe from the rear.

It's a dual filament bulb. If you rotate it by 180°, you just swap broken brake and tail light filaments. The problem is,that brake is 21W and light is 5W. It shouldn't be possible to swap it like that without significant effort.

I've seen this before on INA tensioner for my Cordoba. They grinded away all VW markings, because it was not sold as a genuine VW part, but INA-branded part.

What if you just plugeed the outlet to the booster and try if the issue persists? (not while driving, ofcourse!)

I didn't find any connection from brakes to ECU. The clutch is even weirder, it's entirely mechanical, there's no electronic sensor at all. Brake could be explained by some air leakage from the booster, but I have no idea how clutch could have any effect on the engine, besides small load change from the gearbox. Weird idle and misfires during rainy weather was caused by bad ignition module on my 1.3. but those were notorious for failures, I'm not sure if the 1.6 had similar issue.

That may be the reason for higher pressure, but I don't think it's the cause of overheating. Did it help? I've got one more idea to test out.. bridge the connector on the radiator fan, so it runs constantly. It probably won't be enough to keep the engine cool while running, but if it does something, it may suggest some issue with airflow.

That seems to be correct, as far as I can see in the service manual. Regarding the compression, how precise is the measuring device? If you haven't skim head too much, there's no reason for it to be higher. This is the weird part. The heating works, so there are no bubbles. It cools down on idle, so pump likely works, too. If only high power is the problem, it's like cooling capacity of the system is somehow limited. You mentioned earlier that hoses remain soft, is that still the case?

VW 1.4 16V AFH Besides the drivers side engine mount, it's a direct fit. Do you have a way to test exhaust gasses in the coolant circuit? The way it behaves still gets me thinking about gas bubbles blocking the flow. At idle, the leak isn't as bad, but once running, the pressure in cylinders is higher, which may result in more leaking. Having been through HG issues with 1.3 (as any other person owning this engine), weird cooling issue was the early symptom. Radiator fan switching too late, heater issues, even ruptured coolant hose. Maybe we should double check the coolant plumbing, too? Could you post a couple of photos of each hose going from/to the thermostat body?

Then there must be an issue with flow somewhere. Without thermostat, it shouldn't even warm up. But iirc, you said that heater worked well?

Have you tried removing the thermostat valve and run without it? Just to make sure it works properly and doesn't limit flow. I know it's new, but it's been proven numerous times that "new doesn't mean good"

No idea, I only found that inner diameter of tubes is 7,8mm it should by possible to calculate inner volume of you measure end chambers, it's fairly simple shape.

If your evaporator starts leaking, you'll know the reason. Aluminium isn't the most corrosion resistant material out there, so I'd be careful using anything but A/C cleaners.

Was this with the engine warmed up? The cap has built-in pressure valve, so if it's faulty, it won't build up pressure. The cooling system won't work properly without pressure.

On LHD cars, some screws have to be loosened to lift the box a little to clear the battery holder. The battery is on the opposite side on RHD cars, but I'm not sure if there's something else that may interfere.

I was only able to find PNs. But the hoses have been sold out everywhere. 6U0819373F 6U0819371G