MK1 Audi A3 1.9 TDi not starting (AHU 39****)

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937carrera
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Re: MK1 Audi A3 1.9 TDi not starting (AHU 39****)

Post by 937carrera »

Pin numbers are usually written on the connector blocks, at the start / end of each row.

You might need a torch and magnifying glass to read them, or use a phone, take a photo and zoom in

I have a Cummins engined truck - I have never needed to use the glow plugs on that. However on a Berlingo I have it starts so much better if I wait for the glow plug light to go out.

I'm not convinced that having an OBD port will give you any useful information. The Polo with the shredded exhaust cam belt above had no error codes, but it won't do any harm either.

Have you physically checked the injection timing, as I understand it this is critical.
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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Re: MK1 Audi A3 1.9 TDi not starting (AHU 39****)

Post by Timburrows »

Try tracing the injector pump supply pipe back from the pump towards the fuel filter,my Passat had a small rubbed hole in it made by the protective sheathing around the wiring harness going to the injector pump,took mr very months to find it,a lot of parts were changed before they wanted to change the injector pump for £770,the local electro diesel said the pumps were very reliable and it would be air in the system most likely and that was the problem,total price 1 hours labour very fair

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