mrGutWrench
Top Post Dawg
'03 ALH, 557,000 miles. I was having intermittent power reductions on the road, about once a week for 4 weeks - OK at 75 Mph cruise but stumbling on hills. Despite the intermittent symptoms, it was running fine, good mileage (about 52 Mpg/tank), easy starts. Then a couple of weeks ago, I went on a trip through the NC mountains. The first hill I came to, it threw a P0252 code and went to severe limp mode. Driving on shoulder in second and not exceeding 7.5 Psi boost, I got up that hill in about 15 minutes. From then on, It would cut out at any speed over 55 Mph and hill-climbing was the stuff of nightmares. Sometimes, it would just stumble and turn on the PO252 code (on Scan-Gauge) and go to limp mode. A couple of times, it cut out entirely and I had to bleed injectors but there was very little bubbling in the clear fuel pump line, and fuel came out of the injector fittings quickly -- then it would start easily. It seemed that either cooling down or letting the residual vacuum from the FI pump pull fuel up from the tank.
I got it home and started looking at fuel starvation There was nothing but clean fuel in the fuel filter but I changed it anyway (apparently the fllter was full of fuel at that time). I put my oil evacuator pump on the fuel feed line from the tank at the filter -- that pumps empties the engine in 30 seconds, so I know it really move fluids. It would pull a couple of ounces of fuel and then sputter and and not pull for 5 - 10 seconds, then spit a few ounces and the flow would stop for 5 -10 seconds. After about a minute there was less than half a quart of fuel in the catch bottle.
I took the fuel feed line off the "fuel level unit" (which is the fuel pickup on an ALH, no fuel pump just the fuel pickup is part of this assembly. The fuel pipe from the pickup to the under-hood filter was free and clear.
Next step was to remove the fuel level unit. It was impossible to pull air through the pickup fitting. It's just a rigid plastic tube with a sliding "telescope" extension at the bottom and a coarse strainer which seems molded into the tube. The strainer was blocked with black flakes. There's also a cup-type device on the bottom of the level unit that slides along with the telescoping part of the pick up. There was some black particle-type trash in the bottom of the cup but not a lot.
The unit itself is covered with a very thin coat of a light brown slime (but how do you differentiate between diesel fuel "oiliness" and contaminants??). I don't think that it's been removed or changed in 557,000 miles so who knows what's been through it in that time.
(History - about 8 months ago, I was going to a place that has always had good quality fuel at a good price but I was running low and I ducked into a nasty-looking truck stop. I splashed in 2 gallons to get me 50 miles to the preferred station. I pulled out on the Interstate and within 15 miles, I passed two big trucks running 15 Mph on the shoulder with smoke pouring out of their stacks. Then I passed a truck on the side of the road with the hood open and a mechanic (or driver) replacing a fuel filter, and in 10 miles another one exactly the same. As I pulled into the preferred station, my engine quit so I coasted up to the pumps. After I filled with fresh fuel, it wouldn't start -- no sign of life just like fuel starvation but I knew that I had enough to safely get there. I pushed over to the parking area, put in a new filter, primed it with Power-Service, cracked open an injector, and on the second starter cycle (10 seconds, then 1 minute cool-off), fuel was bubbling, so I tightened up the injector, it started and ran fine. But I always wondered why I had a fuel starvation problem -- and a few trucks within 50 miles of that place -- just after I put a little fuel in my car from an unknown source. In the months since then, I'd noticed very slight signs of fuel starvation, including random PO252 codes and I wondered if there was a bigger problem looming. Now I find out that there was.)
Since I haven't had a car payment in 19 years, I figured I'd invest a little in my '03 wagon so I ordered a new level unit from IDParts, with some new fuel line clips, etc. That should solve the immediate problem. (I know I could have flushed the strainer etc. or even drilled it out -- I drilled my '02 when it was showing signs of fuel blockage in cold weather about 2004, but I was worried about plastic chips and it just seemed best to start with new parts.)
MY BIGGEST QUESTION AT THIS STAGE -- So, now, before I put the new level unit in, I was wondering if I should treat the tank for algae. I don't really have fuel storage or disposal capability -- and of course, since my car ran better and showed fewer symptoms with a full tank, I had just filled it before I began this work -- so I'd like to avoid emptying and cleaning the tank, but I expect it would be the right thing to do. My first plan was to inspect the tank, pull a bit of fuel out of the bottom of the tank with my vacuum pump to inspect for debris, and put anti-algae in the tank but after I do do that, would it just clog filters and cause trouble with dead algae, if I don't empty and clean the tank? (Of course, new under-hood fuel filter, filter prime and clear-fuel pipe prime, new sealing clips, new thermo-T and O-rings, etc.)
I really want this repair to be a reliable and complete repair so I can get my car back on the road. I'd appreciate any comments and suggestions. Thank you, Mr G
03 Jetta Wagon, ALH TDI 1.9L, 5-speed, 557,000 miles. Timing belt done approx. 5K ago by a trusted shop.
I got it home and started looking at fuel starvation There was nothing but clean fuel in the fuel filter but I changed it anyway (apparently the fllter was full of fuel at that time). I put my oil evacuator pump on the fuel feed line from the tank at the filter -- that pumps empties the engine in 30 seconds, so I know it really move fluids. It would pull a couple of ounces of fuel and then sputter and and not pull for 5 - 10 seconds, then spit a few ounces and the flow would stop for 5 -10 seconds. After about a minute there was less than half a quart of fuel in the catch bottle.
I took the fuel feed line off the "fuel level unit" (which is the fuel pickup on an ALH, no fuel pump just the fuel pickup is part of this assembly. The fuel pipe from the pickup to the under-hood filter was free and clear.
Next step was to remove the fuel level unit. It was impossible to pull air through the pickup fitting. It's just a rigid plastic tube with a sliding "telescope" extension at the bottom and a coarse strainer which seems molded into the tube. The strainer was blocked with black flakes. There's also a cup-type device on the bottom of the level unit that slides along with the telescoping part of the pick up. There was some black particle-type trash in the bottom of the cup but not a lot.
The unit itself is covered with a very thin coat of a light brown slime (but how do you differentiate between diesel fuel "oiliness" and contaminants??). I don't think that it's been removed or changed in 557,000 miles so who knows what's been through it in that time.
(History - about 8 months ago, I was going to a place that has always had good quality fuel at a good price but I was running low and I ducked into a nasty-looking truck stop. I splashed in 2 gallons to get me 50 miles to the preferred station. I pulled out on the Interstate and within 15 miles, I passed two big trucks running 15 Mph on the shoulder with smoke pouring out of their stacks. Then I passed a truck on the side of the road with the hood open and a mechanic (or driver) replacing a fuel filter, and in 10 miles another one exactly the same. As I pulled into the preferred station, my engine quit so I coasted up to the pumps. After I filled with fresh fuel, it wouldn't start -- no sign of life just like fuel starvation but I knew that I had enough to safely get there. I pushed over to the parking area, put in a new filter, primed it with Power-Service, cracked open an injector, and on the second starter cycle (10 seconds, then 1 minute cool-off), fuel was bubbling, so I tightened up the injector, it started and ran fine. But I always wondered why I had a fuel starvation problem -- and a few trucks within 50 miles of that place -- just after I put a little fuel in my car from an unknown source. In the months since then, I'd noticed very slight signs of fuel starvation, including random PO252 codes and I wondered if there was a bigger problem looming. Now I find out that there was.)
Since I haven't had a car payment in 19 years, I figured I'd invest a little in my '03 wagon so I ordered a new level unit from IDParts, with some new fuel line clips, etc. That should solve the immediate problem. (I know I could have flushed the strainer etc. or even drilled it out -- I drilled my '02 when it was showing signs of fuel blockage in cold weather about 2004, but I was worried about plastic chips and it just seemed best to start with new parts.)
MY BIGGEST QUESTION AT THIS STAGE -- So, now, before I put the new level unit in, I was wondering if I should treat the tank for algae. I don't really have fuel storage or disposal capability -- and of course, since my car ran better and showed fewer symptoms with a full tank, I had just filled it before I began this work -- so I'd like to avoid emptying and cleaning the tank, but I expect it would be the right thing to do. My first plan was to inspect the tank, pull a bit of fuel out of the bottom of the tank with my vacuum pump to inspect for debris, and put anti-algae in the tank but after I do do that, would it just clog filters and cause trouble with dead algae, if I don't empty and clean the tank? (Of course, new under-hood fuel filter, filter prime and clear-fuel pipe prime, new sealing clips, new thermo-T and O-rings, etc.)
I really want this repair to be a reliable and complete repair so I can get my car back on the road. I'd appreciate any comments and suggestions. Thank you, Mr G
03 Jetta Wagon, ALH TDI 1.9L, 5-speed, 557,000 miles. Timing belt done approx. 5K ago by a trusted shop.