Gasoline in fuel line, what to do.

jnl_public

Well-known member
Joined
Feb 28, 2009
Location
California, US
TDI
2002 Jetta Wagon
Wrong Fuel, fuel restriction and/or both, 3 questions.



I 'may' have put gasoline in my TDI's tank, drove it about 20 miles and then experienced the engine not igniting during the next start. (I say 'may' because I can not recall if I grabbed the wrong fuel nozzle at the station being absent minded.) But the indicator light was on, low fuel, and I put about 2.5 gallons of 'fuel' in the tank.



1. No doubt there's a thread already discussing ways to remove gasoline from ones TDI fuel system (tank to engine), but I haven't found 'the one' that seems simplified and deemed effective on our site yet. If someone can point me to the thread(s), I'd appreciate it.


On the subject, have folks tried flushing fuel out of the fuel tank by pressurizing the fuel return line from the fuel filter with air and then collecting the fuel from the fuel filter intake line? A video on YouTube:
https://www.youtube.com/watch?v=CWK1MybrNRQ&ab_channel=JakeRobinson

shows this being done.


2. Does this method really work?


3. Lastly, if pressurizing the tank in this manner with a 300psi compressor does NOT produce a flow of fuel (nor can one just siphon fuel from the intake line), what could this portend, a faulty fuel sending unit?


Thank you.
 
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drucifer

Veteran Member
Joined
Dec 21, 2013
Location
fredericksburg virginia
TDI
2004 jetta sw tdi pd
Questions 2 and 3
I've never had to drain a tank.
If I did, on my car I'd jump power to the lift pump that you don't have.
I don't have a compressor, do you?
Applying 300 psi to a tank of fuel sounds like a bad idea.
Try a hand vac pump that you probably already have to change your fuel filter and test for vacuum leaks.

Just my .02.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
I've removed fuel from several Jettas. It is rather simple, but a messy hands-on job.

1. Remove the back seat (bottom)

2. Remove the three screws on the round metal cover

3. Unplug the electric connection and move it out of the work area.

4. Disconnect the pressure and return hoses (not a major task)

5. Protect the two hose ends from dirt and debris and push them out of the work area. (blow them out later, see #10 below)

6. Using a blunt chisel, loosen the big black ring that holds the lecvel unit in place.

7. Before pulling the level sensor unit, prepare the work area for spilled fuel (lots of newspaper, paper towels, old rags, etc.)

8. Slowly work the unit up and out.

9. With whatever means you can, remove the fuel. I have a vacuum pump I use.

10. Using low pressure compressed air, from the fuel filter, blow out the two fuel lines back to the tank.

Re-assembly should be obvious.

You may need to bleed the injectors a fair amount to dilute the gasoline diesel mix.

A 50/50 mix of diesel gasoline may not have damage the Injection Pump!
 

jnl_public

Well-known member
Joined
Feb 28, 2009
Location
California, US
TDI
2002 Jetta Wagon
Thank you to those above that offered suggestions.


I feel fairly comfortable accessing the tank as described to siphon off the fuel in the tank. Thanks again.



On the later note, two videos were viewed related to the project as I see it. However, when air pressure was applied to the fuel return line while the fill cap was in place and/or when a slight vacuum was applied to the fuel intake line (both at the fuel filter) the bubble of fuel produced in a collection line off of the intake line barely moved. Is that indicative of a failed fuel sending unit?


Appreciate the problem solving exercise with you guys.
 

Genesis

Top Post Dawg
Joined
Feb 26, 2003
Location
Sevier County TN
TDI
'03 Jetta Wagon
I would NOT apply pressure to the tank -- it WILL rupture, as it is not designed to take pressure in any material amount. Not only is that messy it's potentially quite dangerous. Diesel is not nearly as risky as gas in this sort of situation but do not become complacent -- if you get diesel lit you're in a world of hurt, and if finely divided ("atomized", etc) diesel will ignite quite readily. It just doesn't vaporize at room temperature very well without mechanical assistance (unlike gasoline.)
 

drucifer

Veteran Member
Joined
Dec 21, 2013
Location
fredericksburg virginia
TDI
2004 jetta sw tdi pd
I'm not sure what else a sending unit is supposed to do besides send a signal to the instrument cluster. If there was a bockage in the pick up tube it seems that could affect how fast you could drain the tank. Maybe once you have drained the tank you could give it a blast of air and see what comes out.
 

belome

Top Post Dawg
Joined
Apr 8, 2010
Location
Mid MI
TDI
2002 Jetta GLS TDI 5-speed
I'm assuming we are all assuming you are talking about the 02 in your signature... is that a correct assumption?
 

jnl_public

Well-known member
Joined
Feb 28, 2009
Location
California, US
TDI
2002 Jetta Wagon
I would NOT apply pressure to the tank -- it WILL rupture, as it is not designed to take pressure in any material amount....
Acknowledging your point. In the video referenced earlier in this thread the individual applying a small air compressor to flush fuel from the tank/lines references what he learned on TDIClub's forum. I am hoping to find the thread he mentions or someone knowledgeable with that particular process.

Also, as mentioned earlier, pressurized air has already been applied to the return line of a supposed closed tank/line system with no effect of pushing fuel or air out of the intake line.

I'm assuming we are all assuming you are talking about the 02 in your signature... is that a correct assumption?
Yes. The car is a 2002 TDI with an ALH engine. Why do you ask?




.
 
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belome

Top Post Dawg
Joined
Apr 8, 2010
Location
Mid MI
TDI
2002 Jetta GLS TDI 5-speed
Yes. The car is a 2002 TDI with an ALH engine. Why do you ask?
The newer the version of the car, the less likely the car survives a missfuel event. You can cause literally thousands of dollars of damage in the new TDI's when you subject them to gas and it won't be covered under warranty.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
The thing in the tank is a fuel pick-up. The fuel is drawn in using the Injection Pump. Applying pressure to the return hose would do who knows what, but it won't bring fuel to the filter.
 

jnl_public

Well-known member
Joined
Feb 28, 2009
Location
California, US
TDI
2002 Jetta Wagon
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AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
I suspected it would work as I've used "compressed" air on the fuel tanks of the old MK1s and got the same results.

Considering the return hose goes within millimeters of the pick-up tube in the assembly, the results would be almost the same blowing through it.

But, if you are in Timbuktu and mis-fuel, unless you have a Gastapper, well, follow my instructions.
 

Dieselmonkey02

Veteran Member
Joined
Dec 26, 2011
Location
Edinburg, Pa
TDI
02 jetta
I wouldn’t fret too much. She put a couple gallons of gas in my car once. Hence to say it wouldn’t start after the grocery store. I drained and filled the fuel filter with diesel topped up the tank with fuel, fuel treatment, and a few ounces of 2 stroke oil. Bled the injectors and got on with things.
 

jnl_public

Well-known member
Joined
Feb 28, 2009
Location
California, US
TDI
2002 Jetta Wagon
battle won, war not over?

Thanks to those that have offered suggestions on this thread.


In summary:



  • I opened the gas tank via the port in the cabin and siphoned the fuel out of the tank.
  • Replaced the fuel sending unit with a new one.
  • Pushed some air through the fuel lines from the intake and returns lines at the fuel filter and collected the fuel from those lines back at the gas tank.
  • Replaced the fuel filter, added diesel to the filter.
  • And, using a hand vacuum pump, pulled fuel from the filter through the injector pump from the injector pump return line.
The engine now starts and runs with a small stream of bubbles seen in the intake line pre-IP for a few minutes before the fuel runs free of air. (The engine has only been started once thus far, more observations will prove valuable no doubt in terms of whether or not air leaks into the lines on an on-going basis.)


My last observation posted under this thread's subject may predict more efforts will be needed however. When draining the old fuel filter before be discarded, about an inch worth's of 'orange' cloudy liquid came out of the bottom of the filter when the value was first open. :eek:


After some reflection and further reading up on what that substance may be, I'm coming up it may be coolant that has entered the fuel system via faulty injector cups or a fuel coolant coil.


I need to look more in the engine compartment to learn if my car has a fuel coolant coil and if there, does it utilize radiator coolant.


Then also, consider whether where I have faulty injector cups (a novel item to me). The intake manifold was service over a year ago and I was not pleased that the mechanic asked me when I dropped off the car if it was ok that he source out the job to another shop since his solvent bath was not working. (Seemed kind of shady to inform me about that at the last minute. Maybe the gorilla that he sourced it out to may have been less kind to the injector area, they according to blogs, can be parts that in the work area.)


Anyway, I'm going to start a new thread: http://forums.tdiclub.com/showthread.php?p=5420006#post5420006 on that matter to separate it from the fuel replacing subject of this thread. Thanks again.
 
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burn_your_money

Veteran Member
Joined
Oct 16, 2012
Location
Missouri
TDI
99 Beetle, 96 B4V, 05 Passat wagon
Your fuel is not cooled by coolant and there are no injector cups on your engine. The orange stuff is not coolant unless someone poured it into the tank (not likely)
 

jokila

Vendor
Joined
Dec 3, 2004
Location
Houston, Texas
TDI
2003 Jetta GLS, Manual
That orange crap could have been some crap from a fill up at a fuel station. Your filter did its job.
 
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