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Bad Diesel?

I got a 2010 TDI Jetta SportWagen back in September. Since that time we have had it in the shop 6 separate times because the check engine light keeps coming on. The mechanics have now replaced all 4 fuel injectors, as of two days ago. The check engine light came back on today and we are assuming it is the same problem fault code, fuel injector failure. The mechanics called the VW tech in Denver to consult on the problem and he said that it is possible that we are the victims of bad Diesel that keeps tripping our check engine light for an injector failure.

I doubt that it is bad diesel as my father-in-law has filled up his TDI at the same station for the last 5 years and I have a '00 TDI that I have filled up at the same station for the last 2 years and neither car has had any problem.

Any insight and/or help on this perplexing problem would be greatly appreciated.


whats the fault code number?

Are these the same Bosch injectors now made in China referred to in another thread?

I had similar symptoms a few years ago with my 02 Jetta TDI. I thought it was a glow plug but after it was replaced the “check engine” light came back on. The dealer chased down the fault code and discovered that it was the diesel injection pump (or a bad wire - but I’m never that lucky). The part was $1200! and required 8 hours of labor. I also replaced the timing belt at that time since the pump runs off the flywheel.

Initially my dealer came to the waiting room like a doctor ready to tell me I had a terminal disease and suggested I drive it for a while until I saved money. Over that time the car began to lag when I stepped on the accelerator it became less respsonesive until one day I called the dealer to say “it’s time.”

I looked for rebuilds and decided against it since the mechanicals may be rebuilt the electronics are not and the dealer couldn’t insure it. We did take one out of a wreck and tried it but the electronics didn’t work correctly.

I hope that is not the problem you have, but if you can’t find the problem ask them to look into it so you can know that it is or not this problem. Maybe it’s just the frayed wire.

Good luck

The first car maker who offers a ten year, 100,000 mile bumper to bumper warranty, excluding normal wear items, will put all the other makers out of business…

Cars have just gotten too complex to maintain any kind of reliability…Repair mechanics and technicians have been left behind, leaving the consumer to face staggering repair bills with no guarantee the repair will be successful…

@Caddyman what do you mean with “Repair mechanics and technicians have been left behind”?

I don’t mean this to sound like I’m bragging, but over the years I believe I’ve been a pretty good mechanic. And some of the problems I fixed were ones that other guys couldn’t get a handle on. And some of the problems I’ve fixed were on pretty new and high-tech vehicles.

I will say one thing: Without the right information at their hands, mechanics aren’t as efficient as they could be. I know that firsthand. It’s much easier to diagnose a problem if I have access to the latest factory TSBs, wiring diagrams, etc.

You are right about the 10yr/100k bumper to bumper warranty, though. If such a thing were to happen, the other manufacturers would pretty much be forced to offer the same thing, or fall by the wayside. And the independent shops would see far less business, especially for diagnosis.

We have owned three different diesel cars since 1981 and have never experienced bad diesel fuel. If there was particle contamination in your fuel, the fuel filter would stop it. VW diesels have very good fuel filters to keep particles from wearing out injection pumps and injectors. You might want to sign up and post on to benefit from the extensive experience of VW TDI diesel car owners there.

Cars have just gotten too complex to maintain any kind of reliability..Repair mechanics and technicians have been left behind, leaving the consumer to face staggering repair bills with no guarantee the repair will be successful...

@cadddyman - You should start buying reliable vehicles…Complex - YES…But they are also more reliable. Counting for inflation maintenance costs overall are a lot less then they were 20-30 years ago.

@whawho I was just looking through the old folder for my 81 Olds diesel. At 16,000 miles on it I filled up at a truck stop in DesMoines. About 60 miles out and still 140 miles from home I started losing speed. By the time we crawled home I was down to about 25 MPH top speed. The dealer changed the plugged fuel filter and I was changing filters about every 5000 miles until I finally just drained and cleaned the tank. It was filled with slime, water and who knows but no problem after that. It was a new car and definately was a bad tank of fuel at a high volume truck stop on I35. It does happen. I should have sold it then though since that was just the start of my problems over the next 400,000 miles.

Since you are using a known source of diesel fuel, I think the “bad fuel” is a cope out answer. The VW folks need to to dig deeper to resolve the problem.

@IanMacDonald is probably right on this one. My guess is it is the injector pump. Those pumps are subjected to very high pressures and are more likely to fail more than the injectors. If the IP starts acting up, it is quite possible the ECM would interpret this as a potential injector failure, as it may not have the sensors to be able to isolate between the two. If a copy of the car’s VW Shop Manual is available, I’d expect it to say that the code thrown could be either the injectors or the pump.

I can only assume that your shop is not a vw shop…first thing to try is always the cheep stuff.Replace the fuel filter under the hood (in a tdi you should replace this every year) and lift the rear seat and pull out the sending unit from the tank and look to see if the tank is full of gunk and make sure the filter in the sender is not plugged. go here for video on restricted fuel in tdi.

The first car maker to offer 10 year, 100,000 bumper to bumper warrenty will put himself out of business. The dealer gets more then half their profit from parts and service and the manufacturer could not afford to reimburse the dealer for that amount of time and mileage.

Water in diesel fuel will disable any diesel engine. When I was pulling long doubles ( Thruway Tandems in NY DMV jargon) on the NY Thruway I could tell if the city driver had fueled my tractor at the wrong station before I got the 4 miles to the doubles compound. If I had my own truck I would have bought Wix fuel filters - They had a drain plug on them you could twist open to drain the water.

Cars are infinitely more reliable than those of yore. I’ve kept track of trips to the shop for repairs over the years for the first 100,000 miles. My 1976 Ford Granada made 3 times as many trips as my 1994 Nissan Sentra. My 1988 Caprice was average.

My 2007 Toyota has been in for just one repair, and it was covered by warranty. I expect this car to be even better than the Nissan.

Some of us get confused by the complexity. You can still buy a basic car, which has far more standard equipment than those of 30 years ago, but the reliability will be outstanding. On a sumer holiday weekend you se far fewer cars stuck by the road side and far fewe headlights burned out as well.

If you want a reliable car buy an econobox like a Toyota Yaris, Hyundai Accent and others with a stickshift, no air, no power windows and locks, and you’ll be bored by how reliable it is.