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Engine Specific Info and Questions => TDI Engine -General Info => Topic started by: jlpst94 on July 22, 2014, 04:38:11 pm

Title: No fuel....unless I catch it in gear
Post by: jlpst94 on July 22, 2014, 04:38:11 pm
I have an 02 TDI that will not start with the key.   It turns over fine but will not get fuel.   But..... If I catch it in gear it starts right up.   
Any ideas how or why this could happen? 
New glow plugs
Starter is fine
Battery is fine


Thanks
Title: Re: No fuel....unless I catch it in gear
Post by: jlpst94 on July 23, 2014, 07:11:16 am
I just don't see how the ignition doesn't turn the fuel supply on, but if the car is moving and jumped in gear it starts immediately.   I've never seen anything like it.   
I thought it might be the starter,  but it's turning the car over just fine
Title: Re: No fuel....unless I catch it in gear
Post by: theman53 on July 23, 2014, 08:01:01 am
I don't know what all the x relay controls but I have heard it causing weird issues. search x relay and see what you come up with maybe.
Title: Re: No fuel....unless I catch it in gear
Post by: 410 on July 23, 2014, 09:28:00 am
Sounds like the ignition switch itself.
Title: Re: No fuel....unless I catch it in gear
Post by: CRSMP5 on July 23, 2014, 01:08:20 pm
Thats how mk1-3 fail ignition switches... Never seen mk4 do it... Just rember... From 75 till mk4 vw switches do same as current recalled gm do it... Changed too many of them for same symptoms... Mk4 tend to break hook off key before key ring weight make it fail on mk4...

Just use test light to fuel shut off switch and see if looses power in crank position
Title: Re: No fuel....unless I catch it in gear
Post by: jlpst94 on July 24, 2014, 09:50:07 am
If it starts when i catch it in gear I assumed it had to have power at the fuel selenoid.   I'll check it tonight, i guess there could be a way that the relays, etc.. Change when the vehicle is moving vs when its sitting still and your using the ignitiom. Thanks guys
Title: Re: No fuel....unless I catch it in gear
Post by: bajacalal on July 24, 2014, 01:19:54 pm
Yeah, on at least the mk1s, mk2s and mk3s the ignition switches are really fragile and what seems to go out a lot is the 'hot in both start and run' circuit. There are several terminals on the switch, the battery input and 'hot in run,' 'hot on start' and 'hot on both start and run.' This leads to a situation where the starter works normally, all the accessories and systems work normally in the 'run' position but power is cut to those which need power in both 'start' and 'run,' except the starter, which gets power only for 'start,' so the engine cranks and things test out fine but it won't fire, this affects both gas and diesel models. I've also seen the 'start' circuit not disengage and the starter keeps going. I don't know about the mk4s though.
Title: Re: No fuel....unless I catch it in gear
Post by: Toby on August 09, 2014, 01:42:01 am
Its pretty easy tell if its the 12v is dropping out at the pump. Put a test light on it while you crank it.

I have a 2000 ALH that did similar things. It turned out to be an air leak in IP. Never dripped any fuel or had the tinyest bubble in the clear line ,...but would not hold vacuum. Put a Mity-Vac type vacuum pump on the small nipple of the OUT banjo and pinch the inlet and outlet hoses. If it will not hold a vacuum for several minutes you have found the problem.

Mine went from not starting hot to not starting at all. Resealed the IP and it has never been a problem in the year since.

It will take pulling the pump to do the job. I tried the "on the car" reseal to no avail, so I expect it was on of the ones you can't get on the car.