mvoss15
Well-known member
- Joined
- Jul 31, 2005
- Location
- Indiana
- TDI
- 2014 Audi Q7 TDI, 2015 Golf Sportwagen TDI (previous 05 Jetta TDI, 09 JSW TDI, 05 Jeep Liberty CRD)
I'm looking for some advice - just spent the last 2 hours tonight reading every post I could find on here that seemed to be related to my current issue. Actually, I think there are two issues. Here's the story:
Last Saturday, I went to change my fuel filter. My car is a 2005 Jetta TDI with a PD engine - and early 05 - older body style. I followed my normal procedure, and once everything was hooked up (yes, I replaced the o-rings), I took my handheld vacuum pump connected to the outlet of the filter and attempted to prime the filter. Thing is, however, I could not build up any vacuum - it was like air was somehow leaking into the filter. Just to make sure all was well, I connected my pump directly to the fuel line coming from the tank, and it pulled fuel up just fine. Assuming that my filter must have had a bad seal or something, I put my old filter back on, until I was able to get a a replacement.
So, tonight, I took a second fuel filter, and had the same symptoms. I simply could not prime the filter - I cannot build up any vacuum pressure to pull fuel in. I ended up filling the filter with fresh fuel through the top of the filter (where the T-fitting connects), and then was able to pull fuel through with my vacuum pump, though there seems to be air getting in. Hopefully it will get me to work OK in the morning!
So, first issue: looking for advice - think I have a bad o-ring (I've replaced them twice however), is the t-fitting bad, or something else? Am I risking anything major if there is an air leak if i drive it for a while to see what happens? I read a tip in one post about putting Vaseline on the o-rings - is that advisable?
Ok, now the second issue: in my many attempts to prime the filter, I remembered reading that I should be able to use the lift pump in the fuel tank to do the job. I tried the key-on, wait, key off routine many times, but noticed that I really could not hear any noise from under the backseat. So, for fun, I disconnected the fuel line going into the fuel filter again, wrapped it in a rag, and tried the on-off a few more times. No fuel was coming out. So, it seems that my in-tank lift pump has gone bad. My hunch is that it has not been working for a long time, as I don't ever recall being able to hear a noise from under the back seat. Funny thing, however, is that the car seems to be running just fine without it. Most of the posts I've read about here that refer to lift pump failure talk about the car simply not running - mine's not had any issues.
So, second issue: is it likely that my lift pump has failed? Was my "test" a valid test of the lift pump? Any other suggestions here? And how come my car is running fine, if it in fact has failed? I'm assuming that the pumps in the engine are probably working over-time in order to make up for this?
Any suggestions, advice, alternate theories, etc. would be appreciated. And, if I get stranded on the side of the road on my way to work tomorrow (50 mile commute), I think I'll know why
Last Saturday, I went to change my fuel filter. My car is a 2005 Jetta TDI with a PD engine - and early 05 - older body style. I followed my normal procedure, and once everything was hooked up (yes, I replaced the o-rings), I took my handheld vacuum pump connected to the outlet of the filter and attempted to prime the filter. Thing is, however, I could not build up any vacuum - it was like air was somehow leaking into the filter. Just to make sure all was well, I connected my pump directly to the fuel line coming from the tank, and it pulled fuel up just fine. Assuming that my filter must have had a bad seal or something, I put my old filter back on, until I was able to get a a replacement.
So, tonight, I took a second fuel filter, and had the same symptoms. I simply could not prime the filter - I cannot build up any vacuum pressure to pull fuel in. I ended up filling the filter with fresh fuel through the top of the filter (where the T-fitting connects), and then was able to pull fuel through with my vacuum pump, though there seems to be air getting in. Hopefully it will get me to work OK in the morning!
So, first issue: looking for advice - think I have a bad o-ring (I've replaced them twice however), is the t-fitting bad, or something else? Am I risking anything major if there is an air leak if i drive it for a while to see what happens? I read a tip in one post about putting Vaseline on the o-rings - is that advisable?
Ok, now the second issue: in my many attempts to prime the filter, I remembered reading that I should be able to use the lift pump in the fuel tank to do the job. I tried the key-on, wait, key off routine many times, but noticed that I really could not hear any noise from under the backseat. So, for fun, I disconnected the fuel line going into the fuel filter again, wrapped it in a rag, and tried the on-off a few more times. No fuel was coming out. So, it seems that my in-tank lift pump has gone bad. My hunch is that it has not been working for a long time, as I don't ever recall being able to hear a noise from under the back seat. Funny thing, however, is that the car seems to be running just fine without it. Most of the posts I've read about here that refer to lift pump failure talk about the car simply not running - mine's not had any issues.
So, second issue: is it likely that my lift pump has failed? Was my "test" a valid test of the lift pump? Any other suggestions here? And how come my car is running fine, if it in fact has failed? I'm assuming that the pumps in the engine are probably working over-time in order to make up for this?
Any suggestions, advice, alternate theories, etc. would be appreciated. And, if I get stranded on the side of the road on my way to work tomorrow (50 mile commute), I think I'll know why