1.9 CDTI (150) Engine won't start

**koolrunner** · 19th April 2008, 12:46

I recently drove to the Isle of Skye (460 mls) and as I neared my destination, the engine started to 'misfire', it got worse and when I left to return home I found that I was not able to rev past 3000rpm, I drove back home like this and 11 hours later arrived, during the trip there was a car with a spanner showing on the dash, I now know this to be 'limp home mode'. I took the car to my local vx specialist where they plugged it in to the diagnostic tool, it showed 2 error codes, both relating to no.3 injector but the dealer said that it may be the injector, fuel pump, fuel filter or ECU. I decide to do a bit of investigation myself, so I opened the fuel filter, there wasn't much debris in the filter and definitely no shiney brass fragments that would indicate a pump problem. Next, I found that by disconnecting no.3 injector made no difference to the lumpy running of the engine, but when I disconnected another one, the engine really ran rough. Next I swapped the injectors around, so I swapped 3 for 4 to see if the fault moved with the injector, but when I tried to start the engine it 'turned over' but wouldn't start, the 'limp home' light and engine management lights were on. I checked that fuel was coming out of the injector fuel pipes and it was. I then swapped the injectors back to their original positions and tried again, same result, failed to start. I disconnected the earth side of the battery and waited for 30 mins (don't know why, instinct) but still won't start. I've checked, rechecked and checked again but can not find anything that I may have missed during re-assembly. I found a routine to reset the engine management light on this forum, press and hold the brake pedal and the odometer reset whilst ignition turned on, but that hasn't changed anything, but I do feel that this none starting problem is ECU related. Has anyone any ideas that I may be able to try next? Thanks

**plasma** · 19th April 2008, 22:53

Where to begin....

Misfire, as Vx said injector no.3 i suspect its the wiring to this particular injector. also proved by the test you did by swapping between 3 and 4.. Its a known issue with the loom breaking down and its affects this particular injector no3 because of the way the heat flows across it so i've heard, fix for this is a injector wiring loom repair kit £150, consists of new plugs for injectors plus thicker cabling which i believe is spliced in further up the loom.

Was very dodgy checking fuel coming out of the injector pipes due to the stupidly high pressure which they get squirted out at.

The routine you found about holding the brake pedal and odometer reset is just for a routine service inspection light, and is not related to the spanner light. Disconnecting the battery for 30 mins or so will clear any existing fault codes stored into the various ECU's but this would come on again immediately on the next restart of the engine if the fault is still present.

The fuel system is self bleeding so if any air was trapped it would have purged itself back to the tank. The injectors have flow rates which are programmed into them via the ECU but swapping the injectors around wouldnt have confused the ECU i dont think.

Sorry couldnt be more help but hope that explains a few bits and pieces to you.

**koolrunner** · 20th April 2008, 08:43

The fuel doesn't come out from the injector pipes under a lot of pressure (lucky for me), maybe why it won't start?

Is it possible that trapped air may not have been purged?

I did remove the fuel pipe from the tank at the filter end and emptied the filter. After re-assembling the filter and re-connecting the pipe, I then disconnected all 4 fuel pipes from the rail to the injectors to gain access for the removal of injectors 3 & 4, this is where I checked for fuel.

**plasma** · 20th April 2008, 08:48

There is a low pressure pump to get it up to the fuel filter then a high pressure pump to get it up to 1500bar or whatever the really high pressure is needed.

I'll have a think about it and get back to ya later on