QuestionHoping somebody can shed some light on a problem I just had. This morning while driving home after a long night shift, my 2003 1.8T Passat without warning suddenly lost all engine power and I coasted to the side of the road. I had been doing about 60mph with the cruise control on, smooth interstate rd. The battery light came on as well as the check engine light. I keep a code scanner in the car and when I ran it received code P0130 for the Bank1 O2 sensor. Had the car towed home as it would not start and is now sitting in the driveway. The lights stay on as well as all other electrical components. I can crank the engine but it will not turn over.
Will a failed O2 sensor cause the engine to stop? The tow truck driver opined it sounded like an alternator but with still getting power like I am it makes me wonder. Any advice or recommendations would be greatly appreciated.
AnswerHi Jon;
Sorry to hear about your trouble. Since you carry a code scanner with you, do you also have a digital volt ohm meter...DVOM? The engine in your Passat is an "AWM" engine code motor. Have you had the car serviced recently at your local dealer where they performed any "campaign" actions, or "recalls?" Take off the plastic engine cover with the 3 "DZUZ" fasteners, and set it aside. Look at the top of the engine carefully, for any sign of a broken wire, or dislodged connector...particularly the connector on the drivers side of the air filter box...yeah, I know it's on the passenger side of the engine bay, but I kept on saying right, and left, and people didn't know whether I meant from the front of the car looking back, or the driver's seat, which is what I always meant, so now I just say driver side and passenger side...
OK, the mass air flow sensor is the one at the driver's side of the air filter box, if it is disconnected the engine will run, but poorly, and may die if it is in cruise mode, ie. when there is very little air flow, and a very slight throttle angle. I doubt that that is the problem, but if the 3 way crankcase breather hose campaign was done on your car recently, that MAF connector may have been replaced, but not latched, and could have disconnected. Next, if your car is an early production 2003, with the "AWM" code engine, it could have the older style, or older design ignition coils. I can't tell you off hand what the part number is, but there is a letter that is at the end of the part number, and they started with the letter "C," or "D," and now the letter at the end of the part number is "J," "K," or "L." The 2001 model year cars had a specific recall for these, and were covered, and replaced at Volkswagen expense. One, or two might fail at one time, but the engine would probably still run, if very poorly, but still worth looking at to see what design you have. You don't say how many miles on the car now, but at just about, or almost 5 years old now you could/should have between 60,000, and 80,000 if you are an average American driver, and if you have had the car since new. So, with that said, and having eliminated the MAF, and the ignition system, that leaves only fuel. Have you ever had the fuel filter replaced, and if so, was that recently as well? If replaced, was it done at the dealer with a factory part, or was it done at a neighborhood garage with parts from "Spiffy Oil, and Parts Supply?" If done at the dealer, check for one more thing under the engine cover...a small vacuum hose that is fabric covered, and goes to the front of the intake plenum, and a brass colored fitting. It is probably broken, and you no longer have fuel pressure regulation. Fix the hose, charge the battery(find out what your "at rest" battery voltage is...if below 11.8 Volts, replace it. It's almost 5 years old, too.) If the car will now start, check your battery voltage again, this is now the output voltage of your alternator...if it's above 13.8 Volts with nothing on in the car, at idle, excellent. Have someone help you, if they will, and make the tachometer read 2000 rpm, check the voltage at the battery now, and it should read a little over 14.0 Volts...if it's 13.97 Volts...close enough, but it should definitely be over 13.85 Volts at 2000 rpm...otherwise your new buddy from the towing company got lucky, and guessed right. If the fuel filter has not been changed, it's probably clogged with debris, and can't pass enough fuel to make the car start, or run. If it was changed by the guys at "Spiffy Car Service," join the class action law suit against them, and find a new service facility. One of the quick service companies has a suit charging them with putting used oil, and other used things in customer cars...I can't say who it is, but it should be easy enough to find out. They may even have sent you a postcard to let you know. Finally, I guess, P0130 has a Volkswagen DTC of 16514, O2 sensor circuit, Bank 1, Sensor 1 malfunction. This could mean that the sensor itself has simply stopped working, or it could mean something more like a problem with the connector under the car, or the wiring itself, which goes from the sensor to a junction box under the passenger's front seat, under the car, or the wires that come back up into the engine bay, and go to the ECM...engine control module. It sounds a little like you do some of the maintenance on your car yourself, Jon, do you? Get a "Bentley's" repair manual for your car, and it will show you how to go about changing the fuel filter, and where the O2 sensor junction box is located, and how to get the connectors, and O2 sensors out, if one needs to be replaced. At the age of your car, I would also highly recommend changing the suction jet pump, using the largest oil filter available, using nothing but synthetic oil, and scheduling your oil changes about every 2000, to 2500 miles, and no more, that is if you want to keep driving your Passat. The camshaft tensioner seal is probably leaking oil, and so is the valve cover, I would guess. Finally, finally, the air filter, debris/snow screen is probably clogged, and a Volkswagen brand filter is the only one I can in good conscience recommend, because it fits best, and it isn't covered with oil that will contaminate, and destroy your MAF sensor. None of the maintenance items on Passats are easy. Even the oil change can make quite a mess, when changing the oil filter, but if you place a container, modified to fit into the available space, and remove the engine coolant reservoir to get to it, you can do it quite cleanly, and neatly. I apologize for the length of my response to your question, but I feel that there are several things going on here, and they may all be interrelated, and may have combined, and added to each other in such a way that the engine just quit. Check the oil level too. There is only one sensor input I can think of that would, by itself make the engine not start, or simply quit abruptly, and that is the Crankshaft Position Sensor..."CKP" is the abbreviation Volkswagen uses for this component, and it is located at the very front of the engine, right behind the crankshaft multiribbed belt/serpentine belt pulley. It may be broken, dirty, or wires to it may have a problem. Sometime next week you should be finished with all this, and able to go back to work. Good luck, Jon. I hope you were able to use some of this stuff to your benefit...and your car's benefit as well.
