98 Jetta no fuel at injectors

[Rig]

Our 98 Jetta had a battery go dead. We charged it all night, used a charger/booster, jumped it with another vehicle, and still couldn't get it to turn over because the battery was shot. We were worried last night that the electrical surges might be bad for the electrical components.

So we got a new battery, and the car is happy with it, with a lot of cranking power. But the engine does not fire up.

First, I loosened one supply line at the injector and do not see any significant fuel coming out when the engine is cranked.

Second, I jumped a 12 volt over to what looks like a solenoid on top of the Bosch, and it made some whirring sound. Still no fuel coming out of loosened injector supply tube and no start.

Third, I removed the fuel filter and drained it, just in case. The fuel was clear with no water. I need now to re-fill it.

The car was doing really well. No VCDS fault codes, when it was parked overnight. The cold night and hard start in the morning showed up the weak battery. It usually starts so quickly that the battery doesn't get a workout.

When the car was first cranked with a new battery, it fired up a half a second.

Any help would be appreciated.

 

[whitedog]

Refill the fuel filter then bleed it well before trying to start again.

I'm intrigued about this whirring sound though. The solenoid is on the injection pump just above where the steel lines come out, right? Just for grins, dig in there and pull that solenoid, inspect the O-ring, plunger and spring. Reinstall and try again.

 

[Rig]

I'm putting in a new filter in the morning. But unless I can get the fuel lines to open up, I won't be able to suck fuel through the injector pump to prime it. We put suction on the return line, hoping to draw fuel through the pump--no go.

There is also no suction on the intake side of the pump, while cranking.

The whirring sound is also a little bit of a hissing sound. It makes it for a few seconds when the key alone is used. But it makes it all the time if I jump from the battery to the top of the solenoid.

 

[whitedog]

I'm putting in a new filter in the morning. But unless I can get the fuel lines to open up, I won't be able to suck fuel through the injector pump to prime it. We put suction on the return line, hoping to draw fuel through the pump--no go.

Be sure that you can pull fuel from the tank, then through the filter, then through the pump. Normally this isn't needed, but since you are having troubles, it's best to be sure along the way.

There is also no suction on the intake side of the pump, while cranking.

That's to be expected, don't worry

The whirring sound is also a little bit of a hissing sound. It makes it for a few seconds when the key alone is used. But it makes it all the time if I jump from the battery to the top of the solenoid.

That last part about the whirring gets more interesting. The times are exactly what would be expected for the solenoid to be operating - a few seconds when turning the key on then constant when jumping it. Since I would have to drive to the other end of town to get the battery for my Beetle, I can't do any comparative testing for this, sorry.

I would pull that solenoid out and inspect it before putting in a new filter.

 

[Rig]

I can suck fuel from the tank at the filter. It's good to know lack of suction at the pump is normal. How will I get fuel to go through the pump to prime it?

The glow plug indicator comes on for a normal amount of time (for cold weather) and then go out. All the dash lights appear normal. Cranking is normal and good. Firing is absent, except that it did fire a couple of times when I first tried.

I'm wondering of course whether I ruined some electronic device by trying to coax a bad battery back to life and trying to jump the car with a battery booster.

 

[Rig]

I'm searching for a diagram of the solenoid, or better yet, a guide to diagnosing it.

Will its function or lack of function be apparent when it's out?

 

[whitedog]

It's function will be apparent. Look in the TDI for a post by drivbiwire about injection pumps. It's stickied at the top.

 

[maniaq]

hi rig, i have the same problem as you presently on tdi 1998,but for me the problem occur only around -13c and lower, to get the engine start i have to do a hammer mod on the pump, once the engine start, i need to set down the fueling. like you, the engine crank but no fuel come to the injector. i search many hour on various tdi forum and it seem to be a injection pump problem, but before changing the fuel pump, i find a fix on the web last night. it's consist to overhaul the whole governor to clean and remove all debris and particles stuck between rotating parts and electro-magnet. it's what i've done today, i will see in a couples of days if that fix work for me.
3 hours labor vs a fuel pump change, i think it's valuable test!!

 

[Rig]

This could be related to cold weather, since it happened at about 15 F. But it has had no trouble starting before.

Whitedog, I don't understand how the fuel gets through the injector pump if there is no suction while cranking. And it seems that the passage through the pump is blocked off because I haven't been able to suck fuel through there with my suction pump.

 

[Rig]

BTW, someone mentioned to check the asv, but this AHU doesn't have an anti-shudder valve like the later models. Is there something else that shuts down the engine?

It has always fired up and run very well in cold weather. I think we messed up something when we were jumping the battery and trying to crank it with low voltage. The car was not happy with us, clicking and beeping and setting off the car alarm.

 

[maniaq]

This could be related to cold weather, since it happened at about 15 F. But it has had no trouble starting before.

Whitedog, I don't understand how the fuel gets through the injector pump if there is no suction while cranking. And it seems that the passage through the pump is blocked off because I haven't been able to suck fuel through there with my suction pump.

same thing for me, when i have no start there is no inlet at the fuel pump, i can disconnect the inlet tube and i can see the fuel flush to the fitting. and there is absolutly no inlet of the fuel pump. i'm not a expert in tdi but i think the governor on fuel pump can go in no fuel position, in that case, there is no injection, so no fuel inlet at the pump.

 

[TonyJetta]

Priming the injection pump

Using a mity vac (hand vac pump) on the injection lines won't work.

1) Prime the fuel filter with Power Service - it's clean and you can pour it directly into the opening for the thermostatic T
2) Install the T onto the fuel filter
3) Remove the fuel return line from the injection pump (small nipple)
4) Attach the mity-vac to the hose barb on the injection pump.
5) Draw vacuum, until fuel is seen in the mity vac line. It's best to use a catch can inline with the mity vac. Diesel fuel will destroy the vacuum diaphragm.
6) Check the fuel lines for bubbles. You should see fuel & bubbles. If not, keep pumping.
7) Once fuel is in the IP, and you have fuel in the catch-can, replace the fuel line return onto the thermostatic T. Note that some bubbles are acceptable, so long as the hose has >50% fuel in it.
8) Loosen the injector fuel line nuts, ~1/4-1/2 turn. Do not remove the nuts from the injector lines on top of the injectors.
9) Wrap a rag around all but #1 injector.
10) Crank the engine. Within a few seconds, you should see fuel squirting from #1. Check the rags for #2-4. IF the rags are wet, tighten all the injector lines and crank the engine. If the rags are dry, tighten #1 and remove the rag from #2. Crank the engine until you see fuel squriting. Check the remaining rags, repeat for #3 & 4. By the time #1 & 2 are primed, the engine should try to fire. IF your engine is not firing when #4 has been primed, the IP may need to be advanced a little.

Post back if you have issues or questions.

Tony

 

[Rig]

Maniaq, Where is the governor on the fuel pump? Is it the black unit that screws to it? I think my pump could be different than yours, since it's an AHU.

TonyJetta, thanks for the great instructions. I did try to suck fuel through the small return line coming from the pump--completely closed. I can try again.

How much fuel should I see at the injectors? It's presently like a half a drop, just a wet line when I crank--probably left over from when it was OK.

 

[mrorganic77]

Could the fuel shut off solenoid be stopping the mity-vac from sucking fuel thru the IP? Would a small 12 jumper wire activate the solenoid so fuel would suck thru when trying to prime?

Another thing to check is all the return lines between the injectors and the one cap.

 

[whitedog]

Could the fuel shut off solenoid be stopping the mity-vac from sucking fuel thru the IP? Would a small 12 jumper wire activate the solenoid so fuel would suck thru when trying to prime?

No, it would not.

Is the mityvac pulling a vacuum but no fuel, or is it not even pulling vacuum?

 

[Rig]

It just took a lot more suction and drew more air than I expected. I just trusted you guys and kept up with it until I saw some fuel come through.

I followed ToniJetta's instructions and crossed my fingers, and it fired right up. Lots of black smoke at first, but then evened out. The measuing blocks on the VCDS showed everything just right.

I did get some error codes from goofing with the battery, but they cleared. Supply voltage implausible, glow plug cycle, fuel-stop solenoid bad voltage.

So now I have a new fuel filter, some new clamps, and it is running again! Thanks for all your help!

 

[TonyJetta]

Glad to hear you got it running!

Tony