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Matt, Mechanical Engineer
Category: Car
Satisfied Customers: 22893
Experience:  BEng hons Mech engineering, in auto industry 22 years
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I have a uk 1999 Subaru Impreza, I have replaced the

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Hello I have a uk 1999 Subaru Impreza, I have replaced the original turbo for a larger one and also have bigger injectors and upgraded fuel pump recently. Before this the car run smooth and was ticking over fine, I started it up after the mods and I ticks over fine for 1 minute then white smoke comes from what seems to be under the engine followed 30 seconds later by a knocking noise which is random but gets worse then I turn engine off. The smoke smells like coolant and this would make sense as its in the area of the header tank which was removed and coolant was spilt in this area, however the noise is worrying me. The oil pressure is steady as normal and vacuum on boost gauge is between 0.6-0.8 as normal.
Hello if you've just increased the injector flow without re-mapping the ECU then you'll be over fuelling horribly as the ECU cannot compensate for thisthe closed loop fuel control will cope with about 25% change but it won't make a change to the open loop , high power fuelling so I'd 1st try putting the stock injectors back in to see if this resolves your issue, and only fit them once you're into the re-mapping process
Customer: replied 2 years ago.
Sorry I think I was just hearing things in regards ***** ***** noise there is no noise now at all it ticks over nicely.
Just thick white smoke when idling, I haven't moved it I was just ticking it over to check for leaks as remap is booked for two days time.
Vacuum is good and steady on gauge
Oil pressure is good and steady
No engine management lights
Revs stay steady
Just lots of white smoke from
Exhaust,imobviously worried but I thought natural I would be the fact it's running mega rich and just wanted to put my mind at easy slightly.
Ok if you're happy to run it this rich while awaiting the new map then that's fine if it runs a lot better with some rpm then that would bear this out
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