Question about Volkswagen Passat
The "Check Engine" light or MIL (Malfunction indicator light) illumination, indicates a problem in the engine control system.
A steady light indicates a fault that may cause high engine or evaporative emissions. Under certain conditions the light will blink or flash. A blinking light indicates a severe level of engine misfire that can cause expensive component damage.
A severe misfire causes unburned fuel (hydrocarbons) to pass through the exhaust. When it reaches the catalyst it burns. This is the catalyst's function to burn any unburned hydrocarbons, but NOT the large quantity associated with a misfire. When the catalyst processes excessive amounts of hydrocarbons it becomes intensely HOT and overheats. I have seen them GLOW red and melt adjacent heat shields
. This also damages the catalyst and in many cases warrants it’s replacement.
If the MIL is flashing, I advise you DO NOT drive it. Misfires on this year/model/engine are common. The most likely cause would be a coil. They are located under the black plastic cover on top of the motor. If it is a coil, they are fairly simple to replace and relatively inexpensive. I usually recommend replacing all 4 coils. If not the others often follow within a short period of time. Usually at 1:00 am on a Sunday morning 60 miles from anywhere. If you want to take a chance you could simply replace all coils, but it may not correct the fault. There are other possibilities, but without ALL the specific Diagnostic Trouble Codes (DTCs), a description of the symptoms, when they occur, and how they developed, this is just a guess based on your description as this is BY FAR the most common cause of misfires and the storing of the P0300 series of DTCs.
Coils are very delicate and anytime they are removed it should be done with the special tool. The tool pries out the coil evenly so as not to stress it. If they are stressed they can fail prematurely. Also, I have seen a lot of problems with aftermarket (non-factory) coils so I suggest you get them from the dealer or an OEM (original equipment manufacturer) retailer.
If the MIL is flashing, it's a pretty safe bet the coils will do it, but no guarantee's. I rate it a 3 on a 10 scale for difficulty to DIY replace.
1. Remove the plastic cover on top off the motor
2. Disconnect the electrical connectors at the coils. Be careful you do not break the little tabs that hold the connector to the coil
3. Gently pry up/out the old coils
4. Replace in reverse
The MIL will still be illuminated and must be cleared with a scanner. It should go out by itself, but it may take awhile. If it is still running poorly or flashing, there is another problem and further testing would be required.
Let me know,if needed further assistance.
Hope i helped you.
Thanks for using ' Fixya ' and have a nice day!!
Posted on May 05, 2010
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Tips for a great answer:
Sep 12, 2017 | Tata Cars & Trucks
Apr 14, 2015 | Ford Ranger Cars & Trucks
Jan 30, 2014 | 2002 Volkswagen Passat
Mar 12, 2013 | Cars & Trucks
Jun 14, 2011 | 2006 Volkswagen Passat
Apr 12, 2010 | 2006 Volkswagen Passat
Feb 15, 2010 | 2006 Volkswagen Passat
Feb 18, 2009 | 2006 Volkswagen Passat
Jan 20, 2009 | 2001 Volkswagen Passat
36 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: