Jetta won't start

dernster

Active member
Joined
Mar 28, 2014
Location
Eastern Iowa
TDI
2006 Jetta, 2001 Beetle
I was driving along about 70 mph and the car (2006 Jetta TDI BRM) stopped running like I shut of the switch. It has not run since. I have done several things to resolve the problem. The first of course was to change the fuel filter. I replaced the throttle control actuator as it was giving an occasional error. The gear in it was bad and it did need to be replaced. Still wouldn't start. I check the timing belt for missing teeth. It looks good. I replaced the tandem pump. Still nothing. The engine cranks at 240 rpm and never varies from that. I am not seeing any codes with the OBD scanner. I have not connected VCDS.

I suspect one of two things is the problem. The first is the timing. I have heard of the timing belt "skipping a tooth". I don't really see how that can happen but I have purchased the specialty tools that set the crank and cam timing to a fixed position which should be set the timing correctly. That will either fix the problem or show that it is not a timing problem. The second is that the fuel cutoff switch/valve is bad or not getting power. I am not sure where to locate this. I have located a component that is in the line that goes to the bottom of the tandem pump. I am not sure that this is the fuel cutoff or not. I have scoured the Bentley manual and it has not references to the fuel cutoff. In any case the voltage going to this component is 5 volts. Should I expect to see 12 volts?

Don't know what else I can check. Any input would be greatly appreciated.

Thanks,
Denny
 

tdiatlast

Top Post Dawg
Joined
Jan 21, 2009
Location
Fort Worth, Texas
TDI
2009 Sportwagen (boughtback); 2014 Passat TDI SEL (boughtback)
Have you checked the various electrical grounds? I would have done this first before throwing parts/$$$ at the car.
Also, a low battery might allow the engine to crank w/o enough voltage to fire-up electrical components.
 

crazyrunner33

Veteran Member
Joined
Jul 11, 2006
Location
NC
TDI
'10 Golf(bought back)
If voltage is low, it won't start. Try giving it a jump first. Start with the simplest and cheapest things first. Chaffed wiring harnesses and loose connections can also cause no start issues.

Edit: tdiatlast beat me, I completely agree with them.
 

dernster

Active member
Joined
Mar 28, 2014
Location
Eastern Iowa
TDI
2006 Jetta, 2001 Beetle
I have completely charged the battery and crank it with a boost from the charger so I doubt that is the problem. I will check the grounding points also. The last time I had a grounding problem things got a little flaky. It did not die suddenly but It won't hurt to check anyway.
 

dernster

Active member
Joined
Mar 28, 2014
Location
Eastern Iowa
TDI
2006 Jetta, 2001 Beetle
Yes I have verified that fuel is flowing from the list pump. I have check all the way up to the tandem pump.
 

dernster

Active member
Joined
Mar 28, 2014
Location
Eastern Iowa
TDI
2006 Jetta, 2001 Beetle
Actually I replaced the ASV earlier as the gear in it was completely worn off. It does stay in the default open position as it should when trying to start the car.
 

kbaisley

Veteran Member
Joined
Jul 31, 2002
Location
Midwest
TDI
2006 Jetta TDI 5spd
Look up chaffing for the wiring harness. Its under the airbox, need to peel back corrugated and harness wrap. I am thinking that the minimum RPM was higher than 240 (280 I think?).A worn starter can cause this issue (R&R clean and grease- Take a look at a thread I had back in Jan/ Feb of this year with no start it will confirm the rpm to look for.(My issue was gas contaminated diesel) Several good suggestions to look for with the car. Grounds are under air box, behind both lights, and under wiper arm in cowl by ECU.

Do you have VCDS? Pull errors, if not, when you get the budget, you need to get VCDS. It's worth its weight in gold. Checking to make sure that the belt is good - not jumped also important. If you do not know when this belt has been changed, you need to replace ASAP. Interference motor, you know the story.
 
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dernster

Active member
Joined
Mar 28, 2014
Location
Eastern Iowa
TDI
2006 Jetta, 2001 Beetle
Thank you for all of the feedback! Update: Car is still not running. I have checked the following items:

1. Double check of fuel flow to and through the tandem pump
2. Checked the camshaft timing
3. Changed fuel filter
4. Check 4 grounding points one under each headlight, one on top of strut on drivers side and one under the plastic cover, drivers side on the firewall.
5. Changed the the ASV as the gear was stripped in it.
6. Ran the autoscan feature in VCDS and came up with no error codes.

Three items I plan to check next are:

1. Intercooler hose to the ASV. (I missed that in an earlier comment
2. Check for power to the injectors.
3. Check for bad fuel.

I am not sure how to check for power to the injectors so any input on that would be helpful. While checking the fuel flow I noticed that the fuel seems cloudy. I will flush the old fuel out, prime the filter, tandem pump, and supply line between the two with fresh fuel.

Thanks again for all of your input.

Denny
 

dernster

Active member
Joined
Mar 28, 2014
Location
Eastern Iowa
TDI
2006 Jetta, 2001 Beetle
I forgot to mention that I have also check the wiring for chafing and can't find anything that looks bad
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
Did you check the belt yet for stripped teeth? Have you set it to TDC with the tools to verify the timing?

Edit: I see you checked for missing teeth, but have you set it to TDC for both the crank & cam?
 
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N.CaTDI

Veteran Member
Joined
Apr 9, 2010
Location
NorthBay San Francisco, CA
TDI
2005.5 Jetta
Sounds like he did set it to TDC if he did and it is not starting I would pull the glow plugs and do a compression check to see if something is wrong inside the engine. I assume he has inspected the cam for wear.
 

dernster

Active member
Joined
Mar 28, 2014
Location
Eastern Iowa
TDI
2006 Jetta, 2001 Beetle
Thanks again for the feedback. The cam was replaced about a month before the car died. I did check the timing belt and it looks good. But I think I may have found the problem. I am not sure if I am doing the check correctly but it appears to me that the injectors are not getting any power. I have check the round connector next to the tandem pump. The four connections have no voltage when I turn the key on. They have no voltage even when I crank the motor. The one in the center has 1 - 2 volts when the key is on and not cranking. When I crank it and check for power with a test light it causes the glow plug indicator on the dashboard to flash. All of this leads me to believe that there is a short in the wiring harness or a bad relay. But I do not know what to expect when doing these checks so I am not sure if this is normal or if something is wrong. I cannot find any documentation anywhere to help me on this. If anyone has experience in this area l would very much appreciate your input. I am planning on going under the dashboard and checking for a 109 relay but given the fact that the glow plug light functions normally I doubt that this is the problem. It comes back to a short in the wiring especially because I was driving at about 70 mph and the car died like I turned the key off. I have always suspected an electrical problem. I am not really much of a mechanic but I would really like to get this problem resolved. It is my wife's car which makes the down time much more painful. :-(
 

N.CaTDI

Veteran Member
Joined
Apr 9, 2010
Location
NorthBay San Francisco, CA
TDI
2005.5 Jetta
Thanks again for the feedback. The cam was replaced about a month before the car died. I did check the timing belt and it looks good. But I think I may have found the problem. I am not sure if I am doing the check correctly but it appears to me that the injectors are not getting any power. I have check the round connector next to the tandem pump. The four connections have no voltage when I turn the key on. They have no voltage even when I crank the motor. The one in the center has 1 - 2 volts when the key is on and not cranking. When I crank it and check for power with a test light it causes the glow plug indicator on the dashboard to flash. All of this leads me to believe that there is a short in the wiring harness or a bad relay. But I do not know what to expect when doing these checks so I am not sure if this is normal or if something is wrong. I cannot find any documentation anywhere to help me on this. If anyone has experience in this area l would very much appreciate your input. I am planning on going under the dashboard and checking for a 109 relay but given the fact that the glow plug light functions normally I doubt that this is the problem. It comes back to a short in the wiring especially because I was driving at about 70 mph and the car died like I turned the key off. I have always suspected an electrical problem. I am not really much of a mechanic but I would really like to get this problem resolved. It is my wife's car which makes the down time much more painful. :-(

But there are no error codes with VCDS? that is strange
 

dernster

Active member
Joined
Mar 28, 2014
Location
Eastern Iowa
TDI
2006 Jetta, 2001 Beetle
The saga continues......... I took it to a local mechanic who is supposed to be pretty good with VWs. He checked all the harnesses and said he did not fix anything. However now I am able to communicate to the ECM and it is throwing errors. Since it is getting cold and the car is filled with B100 I removed the fuel lift pump and drained the biodiesel from the tank. The pump was FULL of gunk and may be the cause of the original problem. I cleaned everything completely and reassembled. The pump is dead. VAGcom indicates it is the relay. After ripping the dash apart I found several relays but no indicator as to which relay I need to replace. There is no diagram in the Bentley manual that matches up with what is in the car. <Heavy sigh> Once I figure out the fuel pump I have tow other errors one is the glow plug wiring harness and the other is the injector wiring harness. Just eliminating the errors one at a time. I have all winter to fix this which is why the progress is going so slowly. I will post again as I progress.
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
The sensor in the hose leading to the tandem pump is the fuel temp sensor and it runs on five volts so let that run you down the wrong road.

Certainly clean out the B100 and don't run it in this engine anymore. You may have buggered the injectors already, but that's tough to tell.

It would also be nice to know the whole story. You said earlier that there were no error codes, but then you said that you are now able to communicate with the ECU. We also just found out about the B100.

Is the car completely stock? What is the maintenance history? Who has been doing service and repairs? Was the timing belt replaced with the cam?

Suddenly dieing like that is usually an electrical problem or a timing belt but with the gunk in the fuel tank, it's anyone's guess now. Did you measure how much fuel is coming from the tank? DanG144 has an excellent write up on checking the fuel system.

Earlier you said that you had fuel flow to the tandem pump, now you are saying that the fuel pump is dead. This is conflicting information.

The computer doesn't say the relay is bad. It may say that there is a problem associated with the relay, but that doesn't necessarily mean the relay is bad. It just gives you a direction to start testing.

Can you power up the fuel pump at the pump connector? If so can you power it up at the relay? If so, check for proper power and ground to the relay. It probably has constant power and the computer switches the ground so don't be surprised if you find power but no ground.

But, since you have errors for the injector wiring harness. This is where your problem probably lies. Where did you check the wiring harness and what were you looking for? These wire looms are notorious for chaffing from the inside out so you have to open the harness to find the problem.
 

dernster

Active member
Joined
Mar 28, 2014
Location
Eastern Iowa
TDI
2006 Jetta, 2001 Beetle
I have the car running like a champ for quite a while now but I am finally getting back to the forum to share the fix. To address the latest comment, I have been running b100 for over 80,000 miles in this car with no fuel related problems. Biodiesel success depends on the quality of the biodiesel you use. And it generally known that you can run b100 in any VW 2006 or older but not in the 2009 and newer models. You are correct I did state earlier there were no error codes. Only after I took it to a local mechanic did the error codes appear. After getting the car back from the mechanic and getting the new error codes and still not running I removed the fuel pump from the tank. The tank was spotless but the housing around the pump was pretty messy I cleaned it up and put it back in. The car still wouldn't run. I could not find wiring diagrams of that matched my car to run down the error codes. The Bentley manual I had did not have the same diagrams as what is in my car. Anyway I finally broke down and took it to a mechanic with a great reputation (and a 3 hour drive each way). He discovered the fuse for the fuel pump was missing and one of the injectors was unplugged. Since I had not taken off the valve cover or remove fuses I can only conclude that the local mechanic was the cause of those two problems. So when the "good" mechanic inserted the fuse and connected the injector the car runs perfectly. and I have driven it about 20,000 miles (on the same biodiesel) since then. The only thing I can a assume is that cleaning the fuel filter module in the tank is what fixed the problem. That would be consistent with the initial problem of not running and no error codes. I suspect that the fuel was entering the module at a very slow rate (due to the it being so messy)which would not start or run the car but enough that when I was testing the pump by disconnecting the fuel line and turning the key to on it would send enough fuel to make me think it was working. Anyway I am somewhat wiser for the experience. Again I thank everyone for their comments. This was sort of a strange problem but I did finally get it figured out with all of your help. I hope someone that has a similar problem reads this and finds the answer easier and faster than I did.
 
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