Passat 1.8T: Loud Engine Noise? Causes & Fixes

Good day, esteemed colleagues.

Perhaps my contribution doesn't belong here, but anyway...

I have a VW Passat 1.8 T, manufactured in 2001 (model year), with engine code AWT. The odometer shows approximately 47,000 km. I bought the car six months ago with only 27,000 km on the clock. The history has been checked, the mileage is correct, and all receipts and the maintenance book are available. Since buying the car, I've experienced nothing but problems. The biggest issue is a very noisy engine.

When I accelerate, the engine starts to 'gurgle' noticeably from around 2000 RPM. Above 3000 RPM, it feels like you're driving a sports car. Additionally, there are noticeable vibrations in the steering wheel, gear lever, and pedals. Otherwise, the car pulls normally, the top speed is correct (approximately 220 km/h), and the fuel consumption is normal.

The first workshop has inspected the vehicle multiple times and replaced the following parts:

4 spark plugs (one defective, engine was running on three cylinders intermittently).
Dual-mass flywheel, pressure plate bearing, pressure plate, and clutch.
AGR valve.
Hydr. Chain tensioner.

They also conducted various test drives, measurements, and other inspections, but without success. In some cases, the costs were covered as a gesture of goodwill, but I still ended up paying over 500 EUR. Ultimately, the workshop refused to carry out any further work.

I then went to a second workshop and also filed a complaint with the Volkswagen representative in Slovenia and Volkswagen Germany at the same time.

The second workshop found several errors that the first workshop had made, and they replaced the following parts:

Spark plugs.
Oil (5W40 instead of 0W40).
Mass airflow sensor.
Hydraulic tensioner for timing belt (damaged by the first workshop; timing belt and other drive components were replaced at the same time).

The workshop submitted a goodwill request for an engine replacement, but the request was rejected.

They also conducted various test drives, measurements, and other inspections, but without success. In some cases, the costs were covered as a gesture of goodwill, but I still ended up paying over 500 euros.

The Slovenian Volkswagen dealership also conducted a very short test drive and found the vehicle to be acceptable. It was strange that a service technician from the dealership (who was present during the inspection) also felt the vibrations and heard the noises, but his boss had a different opinion. In the end, I was even asked to leave the boss's office. Volkswagen Germany remained in the background throughout the process, and the problem was supposed to be resolved by the Slovenian branch.

Then I went to a third workshop (which was not an authorized Volkswagen service center).

The workshop found a bent and therefore leaky exhaust manifold, the flexible exhaust connection was also completely stiff, and the front exhaust support bracket was incorrectly installed. The engine mounts were also checked. The workshop also found a leak in the air intake pipe at the intercooler inlet. Further work was estimated at €200. However, none of these repairs solved the problem.

Despite all the work done, the vehicle is still very loud, and I have the impression that the engine is resonating strongly. The wheels, tires, drive shafts, and transmission have been checked and are okay, as are all parts of the engine mounting system.

Does anyone have any good advice on what else I can do to get the vehicle back in working order? Has anyone experienced similar problems? Can someone recommend a good workshop in Germany? I'm really desperate now. I would be very grateful for any tips.

Best regards from Slovenia.

Motronic.

Hi,

Even if it doesn't explain the vibrations... are you absolutely sure that the exhaust system is still completely original? Maybe the previous owner tampered with it and, for example, emptied out one of the silencers.

Best regards,

January.

If it's very loud, I would check two things:
1. Exhaust system (total length including the exhaust manifold). If the car has been in an accident before, the system might be stressed. There might be a hole that isn't immediately visible.

2. Check the engine mounting: Is the engine properly aligned? It might be stressed or making contact somewhere.

Definitely postpone those expensive repairs for now! It's crazy to replace so much without thinking!

Hello,

The exhaust system is completely original and not stressed. The pipes are quite rusty or appear burnt. The cause has not been found. The catalytic converter is fine. I only replaced the flexible connection, which was very stiff and immobile. We also checked the engine mounts but didn't find any defects. Does anyone have a tip on how to properly align engine mounts? Otherwise, the vehicle is accident-free and in very good condition.

Best regards,

Motronic.

'This type of noise usually comes from the parts that are in contact with the road. It's best to test this with a second set of tires (summer/winter). Also, check the front and rear axles, as well as components like shock absorbers and springs, for damage before replacing anything arbitrarily.'