RepairPal is your advocate for car care advice and guidance

Q: My car has started to make a loud rattle noise at start & foul smell. Why? on 2001 Volkswagen Passat

The faster I go and then slow down, the louder the rattle noise will get. I have been told to stop driving the car, but no one has been able to tell me what should be replaced/ fixed. Here are the codes that I received from Pep Boys: P0430- catalyst bank 2, P0420- catalyst bank 1, P0300 Random miss, P0306, 6 miss P0305, 5 miss, P0154 O2 circuit, no activity B2s1, P0174 Bank2 too lean, P0304, 4 misfire, P0051 Heather control circuit low, B2s1---Also, they did not have the tools to check the timing belt and my Uncle (VW owner of 25 years)states that I should replace the timing belt, water pump, and thermostat-- before any mechanic has actually been able to look at the the timing belt. Any help would be AwEsOmE.
Get a Repair Estimate
Guaranteed by certified locations nationwide. Learn more
RepairPal estimates are guaranteed at over 1,700 quality certified locations nationwide. Learn more
This is an impressive list! I can tell you from what I see here the cluster of o2 sensor codes and random miss codes you probably do have a timing belt issue. One other option, the rattle noise plus smell can indicate a fouled or plugged catalytic converter. This will cause backpressure which can trip the o2sensors and lean codes and blow a hole in your resonator (flex-pipe) which will cause exhaust to come up through the floor and windows when open (your foul smell). Look into getting the timing belt and have catalytic checked. As for thermostat and water pump, if you are not having engine overheating issues I would say you can hold off on those for now till the other issues are resolved.
I appreciate your response. My original problem was ... No heat, believe it or not. My uncle told me that he changed the spark plugs on cylinder 6 last month, so it is not misfiring. Also, he confirmed that it is not the cat converter? Basically, I just wanted to make sure that I am not spending $1600 on timing belt/ misc/ labor if it is not due and there is another issue. Do you have any suggestions on a location that can check the other things that you mentioned?
| |
i agree and also a plugged cat will cause your misfire data.the o2 heater circuit is probably just a failed sensor
| |
Absouletly agree with other answer, but I would push towards the cat converter not functioning 1st then move into Timing belt concerns. The belt should definetly be changed no later than 100k. We just did a top engine job on a 01 VW Passat with 156k because the timing belt snapped causing bent valves. It can get pretty expensive when internal engine parts are damaged. We have a Timing Belt special going on this month 4 cyl $199.00 plus shop fees & Tax
I have been told that I will definitely need timing belt and timing belt components kit, crankshaft seals, and 2 camshaft seals. Also, it was highly recommended to replace the serpentine belt and water pump at the same time. I am sure that my car requires a timing belt, due to the fact that a tune up was not done on my car prior to purchasing the vehicle, so I'm sure the timing belt has never been replaced either. Should I take my car to have the cat converter checked prior to having a mechanic look at the list of things above, OR, can I bring my car to your complete car care location to have the cat converter checked to make sure that does not need to be replaced also? OoOoOh I'm glad I love this car or all these repairs might not be worth it! ;)
Didn't find what you were looking for?