Hi
Though this is my first post in here, I have been reading and searching this forum a lot for the past time, but haven´t found anything conclusive regarding my "hard start" issue.
So we have this really annoying problem with my wifes car (2001 1,9 TDI PD 101 ATD, 390.000 km). It began early this autumn, where it at first could be hard to start if left for a couple of days. The engine would initially fire up, but then die after only a second or so. Afterwards it needed around 10 seconds of cranking, before it would, reluctantly, start up. It seemed to help if you turned the ignition on and off 3-4 times before trying to start the engine at first (I would hear a remarkable squish when the pump primed the system). Later the problem got mere frequent, and the best way to start the engine would be to press the accelerator pedal simultaneously with the cranking. This meant that the engine would, typically, start at once, though idle could be a little rough for the first couple of seconds. The last month the problem worsened, which meant that even though the accelerator pedal was activated during start, the engine wouldn´t catch on immediately. When ever the car runs, it runs great, and mileage is spot on. Before autumn it fired up with out any problems, even in the coldest of winter. I replaced the fuel filter just before we went on summer holiday, and at the time I noticed that most of the fuel lines were very brittle.
After the starting issue began, I replaced all the rubber fuel lines in the engine compartment, the o rings on the fuel filter T (didn´t do this when changing the filter at first), and the tandem pump.
None of this improved starting noticeably. 3 weeks ago I then fitted a non return valve in the fuel feed line between the fuel filter and the tandem pump, and all of a sudden the starting problems were gone. Even when the car had been left for 5 days in a row it just started instantly. But unfortunately my luck was short lived. A couple of days ago after a Christmas visit, the issue was back even worse. The car had been parked on a slope, with the front facing up. It was a real pain to get started. Then today I went to my dads garage to clean the EGR valve (small holiday project I had planned), and it started just as bad as the other day (didn´t even fire up shortly as it used to, just cranking for ~10 seconds before it would slowly rise from the dead ).
I also noted that the squish sound didn´t appear any longer.
3 hours later when I was going to head home it would once again not start. Earlier on the car would pretty much start instantly, if it had been running within the last 12-24 hours. So it seems that the issue all of a sudden has worsened. When cranking the engine for extended periods of time it doesn´t seem to smoke or smell more than normal. Having a full tank or facing the front slightly downwards doesn´t either seem to change anything.
So where to go next? I guess it could be injectors seals (but then why would it recently start immediately after 5 days of standstill in a row)?
Lift pump (seems to work, as it pressurized the fuel system hard enough to shot off an unclamped fuel line when doing a diesel purge a couple of weeks ago). Or can a lift pump that is working still leak air?
I have a gut feeling, that the problems began after I replaced the fuel filter (Bosch), but I don´t have any proof supporting this. Should I just start off with replacing the fuel filter and thermo T?
Are there any non return valves in the fuel system on a PD that could go bad?
Every advice and suggestions will be very appreciated, as this cranking is making me cranky!
Though this is my first post in here, I have been reading and searching this forum a lot for the past time, but haven´t found anything conclusive regarding my "hard start" issue.
So we have this really annoying problem with my wifes car (2001 1,9 TDI PD 101 ATD, 390.000 km). It began early this autumn, where it at first could be hard to start if left for a couple of days. The engine would initially fire up, but then die after only a second or so. Afterwards it needed around 10 seconds of cranking, before it would, reluctantly, start up. It seemed to help if you turned the ignition on and off 3-4 times before trying to start the engine at first (I would hear a remarkable squish when the pump primed the system). Later the problem got mere frequent, and the best way to start the engine would be to press the accelerator pedal simultaneously with the cranking. This meant that the engine would, typically, start at once, though idle could be a little rough for the first couple of seconds. The last month the problem worsened, which meant that even though the accelerator pedal was activated during start, the engine wouldn´t catch on immediately. When ever the car runs, it runs great, and mileage is spot on. Before autumn it fired up with out any problems, even in the coldest of winter. I replaced the fuel filter just before we went on summer holiday, and at the time I noticed that most of the fuel lines were very brittle.
After the starting issue began, I replaced all the rubber fuel lines in the engine compartment, the o rings on the fuel filter T (didn´t do this when changing the filter at first), and the tandem pump.
None of this improved starting noticeably. 3 weeks ago I then fitted a non return valve in the fuel feed line between the fuel filter and the tandem pump, and all of a sudden the starting problems were gone. Even when the car had been left for 5 days in a row it just started instantly. But unfortunately my luck was short lived. A couple of days ago after a Christmas visit, the issue was back even worse. The car had been parked on a slope, with the front facing up. It was a real pain to get started. Then today I went to my dads garage to clean the EGR valve (small holiday project I had planned), and it started just as bad as the other day (didn´t even fire up shortly as it used to, just cranking for ~10 seconds before it would slowly rise from the dead ).
I also noted that the squish sound didn´t appear any longer.
3 hours later when I was going to head home it would once again not start. Earlier on the car would pretty much start instantly, if it had been running within the last 12-24 hours. So it seems that the issue all of a sudden has worsened. When cranking the engine for extended periods of time it doesn´t seem to smoke or smell more than normal. Having a full tank or facing the front slightly downwards doesn´t either seem to change anything.
So where to go next? I guess it could be injectors seals (but then why would it recently start immediately after 5 days of standstill in a row)?
Lift pump (seems to work, as it pressurized the fuel system hard enough to shot off an unclamped fuel line when doing a diesel purge a couple of weeks ago). Or can a lift pump that is working still leak air?
I have a gut feeling, that the problems began after I replaced the fuel filter (Bosch), but I don´t have any proof supporting this. Should I just start off with replacing the fuel filter and thermo T?
Are there any non return valves in the fuel system on a PD that could go bad?
Every advice and suggestions will be very appreciated, as this cranking is making me cranky!
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