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1.9TDI Leon (2006) Warm Weather Start Problem

Jeff Harrison

Active Member
Jul 17, 2018
1
0
Hello everyone,

I own a 2006 Seat Leon 1P1 Mk.2 1.9TDI. Since the weather has warmed up, I have been experiencing increasingly more frequent starting issues. In the early Spring, the engine would start cold, every time, without issue. After a drive, it would start but after several attempts. As the heat has increased, the car will only start on cold mornings. Even after not being started for days, if sun is on the car, it will not start. It will turn over, no issues, but won't fire. I have replaced the engine temp sensor, the cam belt sensor and have confirmed that my fuel system pumps are working appropriately (all suggested fixes on the Mk1 forum). The starter is strong and the battery is new. Nothing seems to fix the issue. I have the Airbag and Traction Control lights steady on the car, but cannot find any faults to explain them. It should be noted that if I turn the key to the on position, but not crank, the engine fans kick on and run continuously, even if the car has been dormant for days and the temp reading is bottomed out. It has been suggested that it may be a dodgy or malfunctioning ECU, but I cannot find the thing for the life of me. Can anyone suggest any further things I can try or advise where the ECU is??? I have found a ECU for £120 shipped, but need to know where It is located on my car to fit it. I have found buckets of information on the Mk1 Leons, but not a sausage on the Mk2. All I can say is the ECU is not on the Mk2 where it was on the Mk1. If the car does crank, it runs like a dream, with no hesitations, shifting issues or power issues. It is only averaging about 42mpg though, which is much lower than it should based on my commute. Please help, as I am on the verge of scrapping a nice clean car.

I look forward to any feedback.

Cheers,Jeff
 

maciek.snow

Active Member
Mar 21, 2016
61
9
Poland, Krakow
Hello everyone,

I own a 2006 Seat Leon 1P1 Mk.2 1.9TDI. Since the weather has warmed up, I have been experiencing increasingly more frequent starting issues. In the early Spring, the engine would start cold, every time, without issue. After a drive, it would start but after several attempts. As the heat has increased, the car will only start on cold mornings. Even after not being started for days, if sun is on the car, it will not start. It will turn over, no issues, but won't fire. I have replaced the engine temp sensor, the cam belt sensor and have confirmed that my fuel system pumps are working appropriately (all suggested fixes on the Mk1 forum). The starter is strong and the battery is new. Nothing seems to fix the issue. I have the Airbag and Traction Control lights steady on the car, but cannot find any faults to explain them. It should be noted that if I turn the key to the on position, but not crank, the engine fans kick on and run continuously, even if the car has been dormant for days and the temp reading is bottomed out. It has been suggested that it may be a dodgy or malfunctioning ECU, but I cannot find the thing for the life of me. Can anyone suggest any further things I can try or advise where the ECU is??? I have found a ECU for £120 shipped, but need to know where It is located on my car to fit it. I have found buckets of information on the Mk1 Leons, but not a sausage on the Mk2. All I can say is the ECU is not on the Mk2 where it was on the Mk1. If the car does crank, it runs like a dream, with no hesitations, shifting issues or power issues. It is only averaging about 42mpg though, which is much lower than it should based on my commute. Please help, as I am on the verge of scrapping a nice clean car.

I look forward to any feedback.

Cheers,Jeff
Hi Jeff, it's either a starter issue or the injector seal issue. I would start with the Starter.
The problem is that if it doesn't do a specified rpm upon startup, the quantity of fuel injected is insufficient for a successful start. If it's the injector seal issue (they wear sometimes). Some people go to a tuner and increase the injection quantity for a hot start. But it's just masking/covering the issue - not solving the cause.

The thing is when ECU sees that your motor is warm. It will not give same injection qty as for a cold engine. ( it will be a lower qty ) so the starter needs to be in good shape and the injector seals.



Wysłane z mojego SM-G930F przy użyciu Tapatalka
 
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DPM Performance