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Polo Starting Problems

3678 Views 2 Replies 2 Participants Last post by  Mullers Diesel
Can any one please help me with a Polo 1.9Tdi ASZ code engine with 83000Km.
The engine fires up and then dies, sometimes it will idle for a maximum of 30 seconds.
When it idle's there is no throttle respons, and it just smokes black, like it stays in excessive starting fuel. I have disconected the EGR system and exhaust and intake throttle body.
When testing it with my Bosch KTS550 I get a Error 4141 "Rpm sensor signal improbable".
I have measured the sensor all the values are according to Bosch specs, it gives 490ohms and gives the correct signal on my oscilliscope for the few seconds that it idles. I have replaced the water temprature sender unit. I have verify the cam to crank timing marks and set the Injector settings to zero travel and 180 degrees back. Fuel pressure at cranking is 2 Bar and at idle 8 Bar. This all happend just after the turbo impeller shaft broke at the intake side just after pulling away.
Any help would be appreciated.
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Hi thanks for your input, yes it have hydrolocked and I have removed the cylinder head to ckeck the piston heights ( bend conrod ) and removed the sump to see if the bigend's are fine.
I have cleaned the manifold and intercooler, at the moment the exhaust is not connected to the turbo and the intercooler pipes are disconneted , also the EGR pipe and valve on the intake are diconneted. I have run a diagnostic test with my Texa equipment, it tell's me that the engine speed sensor outside set range P0726, is the sensor faulty or is the crank timing ring out of range ? I don't understand the code as, I have not removed the speed sensor or timing ring.
The Bosch KTS ask for 3 - 9 mg fuel to be injected at idle speed. At the moment it stays on 43mg when it idles for not more than 30 sec, and then you see on the Laptop the ECU cut the fuel and the engine dies, What els besides the coolant , fuel and air sensors wil keep the ECU in starting fuel mode.
The VW agent don't have a engine speed sensor in stock. It looks to that at the end I will have to take R600.00 and order a new sensor and try it ???
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