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No Codes, No Start, Cranks Fine

8K views 16 replies 5 participants last post by  jfoj 
#1 ·
Hey so I'm having a problem with my car- it started after I got an oil change at Jiffy Lube :( I told them I didn't need anything checked, I just needed new oil and to get on my way.. they had her for over an hour...

What Happened:
1) Started Loosing Power on the freeway, would jump back in after a few seconds
2) couple weeks later died while I was driving slowly (25mph) started back up and got me home
3) Next day wouldn't turn on- still no codes.

What I've Check:
1) Battery is good,
2) Fuse box is getting full voltages on top
3) Fuel Relay clicks on (it's a replacement from about 8 months ago)
4) Voltage to fuel pump is about 8-10V when cranking (measure on pins 1 and 4)
5) resistance doesn't show up in fuel pump (remains at 1 when on 200 Ohms)

Fuse 28 looked good, I lightly scrapped it clean anyways..

My Thoughts:

Bad Fuel Pump?
Crankshaft Sensor?
--The only reason I lean towards the latter is because of the timing of events and considering it's so close to the oil change :(

Would I just need to get a new cranksensor to determine if that's the problem?
 
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#2 ·
Get a $3 can of starting fluid and spray a good 2 second burst into the MAF opening. If the engine starts and dies then you have a lack of fuel.

Check to also see if the Tach moves when cranking the engine. Most vehicles the Tach will move to the 150-200 RPM range while cranking and this is often a good indicator that the crank sensor is reasonably good as long as the Tach signal is stable.

Have not heard a lot about fuel pump failures in the Beetles, but I have a new one coming for my car that I am replacing as PM because I am sending the car off 1100 miles away with my daughter as school for a few years.

Figure I could let the pump fail on its schedule or replace it on my schedule. Pumps last about 5000-6000 hours, keep in mind you cannot determine a pumps hours by mileage. For every second the engine runs, the fuel pump runs. So while you are stopped at a traffic light, the mileage does not move, but the hours continue to tick away!
 
#4 ·
I'll head down and get some starter fluid this afternoon! I have almost 190k on the car and have had her for 3 years, it looks like it could be the original fuel pump (2002)

For the spark plugs, I haven't checked- but I replaced them less than a year ago and got real good Bosch ones (almost 20$ a piece!) I'm also guna try and replace the fuel filter.. I kinda just wanna touch eveything they looked at, I was thrown off by the 8-10V to the fuel pump..
 
#5 ·
Too long without a car...

So it's taken me this long to get some more diagsnostics on it. I'm super frustrated because I have to survive without a car (my commute to school is a 15 mile bike ride and I normally have studying after I get home)

SOOO

New fuel filter in no difference.
Changed the relay out with a good one, no difference
Starter fluid in the MAF starts then turns off.

I have not directly checked the sparts yet due to lack of a helping hand (my hood doesn't stay open either). I assume since it started with the fluid that means the sparks are good. I have one code- injector one low- it came up with a handful of others when the battery died (trying to start it too much). All but that one left after the battery was charged on a charging and testing station (battery is still good).
 
#6 ·
#8 ·
Personally I do not do a lot of fuel pressure checks on older, higher mileage cars. Electric fuel pumps do not last forever and they are reasonably cheap in the big picture.

There are so many cases where the fuel pumps also become intermittent and/or soft fail causing headaches and other driveability problems.

These cars have Siemens/VDO fuel pumps like the BMW's of the era and the BMW pumps seem to be failing consistently around 4000 hours, which is a big young IHMO.

See this link for pictures of the fuel pump out of my 2006 BMW with 84k miles, this failed about a year ago so the car was only about 9 years old a the time.

Note, for every second the engine runs, the fuel pump runs, so mileage is not always a good indicator of fuel pump lifespan. My car was a city/urban dweller, so I estimated and calculated the hours to be around 4000 or slightly less.

The commutator was worn over 1/8" which is very unusual IMHO. Also the brush wear was uneven, very uneven. One brush was worn all the way to the copper braided wire embedded in it. This may be due to the way the fuel pump is on an angle in the sending unit?? See DropBox link below.

I think I paid about $126 for my Siemens/VDO pump without the sending unit from AutoHausAZ which had the pump on sale and free shipping. You need to check and see if your fuel tank has a plastic or metal retaining ring, it affects which pump you buy. The sending unit is easy to swap, but overall this pump replacement is kind of a PITA to get the pump gasket seated in the tank opening while the pump is in the opening. Much more difficult than a similar era BMW.

BMW fuel pump cut open - https://www.dropbox.com/sh/tdx5kech2h6mvha/AADAzsixZq5PcF63WsRmk2Pxa?dl=0
 
#9 ·
Good lookin out. I had a guy from oriely's come and look at it (bad idea) told me it wasn't the fuel pump bc he heard it priming (although I now know that doesn't necessarily mean anything) he let me swap out some parts to test common things but yeah nothing worked. I know my baby is a good one overall but I just don't have the time to sit and fix her- I don't have another car to drive. 3 weeks now I've been biking, I Uber-ed home today... as soon as I get her running I'm guna sell her :(
 
#10 · (Edited)
#16 · (Edited)
Glad you found the problem and got the car fixed and back on the rod. We are seeing allot of fuel pump failures; as most of our cars are over 10-18 years old and they are worn out. You purchased a rebuilt fuel pump; what brand and part number was it? I have never heard of such a thing; get a high quality oem fuel pump: genuine VW, VDO or Bosch only recommended. Cheap sub $100 fuel pumps; from your typical discount auto parts stores, do not last or end up giving you drivability problems (typically they cannot maintain proper fuel pressure needed). There are some parts you can go cheap on; the fuel pump, should not be one of them.

PS: it is a good idea to replace the fuel filter as well and check the fuel pressure regulator for leaks, @ 190k it maybe a good idea to replace anyway.


Sent from AutoGuide.com Free App
 
#17 ·
No such thing as a $45 rebuilt fuel pump, it is used. Replace the pump with a new, quality fuel pump. It is not if, but when any of these pumps will fail. I am very active in the BMW community and pumps last about 8 years, then it is anyone's guess to when they will fail. I find that mileage is a misleading gauge for pump life.

Fuel pumps are rated in hours. For every second the engine runs, the fuel pump runs. About 5000k hours is a pump lifetime. A highway warrior may only have 3500 hours at 140-160k miles, but a city dwelling car may have 5000 hours at 80-90k miles.
 
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