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faults any help please

562 Views 4 Replies 3 Participants Last post by  G11WLT
had my car on diagnostics this morning, got a few faults if anybodys ahd these could give me a insight got a rough idead but just asking advice

pressure drop between turbo and throttle

mass air flow sensor signal too low

oxygen heating sensor heating performance too low

fuel trim bank system too low

cylinder one misfire detected

have got new coil pack and plugs going to change these hopefully sort the misfire out, guess the maf is faulty so will have to change this any other things i can look into will be of great halp thanks
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I am Not an Expert but...

The Pressure drop between Turbo and Throttle, could be split or loose hose connection?

Mass Air Flow meter too low, Hot wire meter, could be gunged up (Overtime), try cleaning by spraying Carb Cleaner Wynns/ Holts supply, avail Halfrauds or motor factors. Only spray dont use anything abbrasive in the Very delicate gubbings inside.

O2 sensor, 4 wire component 2-heater, 1-Ground and sensor feed to ECU, probably sensor Difficult to Change.But have a good look at connections for Verdigre and corrosion?And any damage?

Fuel trim low, there is a Fuel pressure regulator in system should be 2.5 Bar, I'd get a Garage with appropriate test equipment to check. Failing that there will be a Shreader (Tyre inflation valve) connector for testing whilst system pressurised.(Inlet manifold side)

Cyl 1 misfire probably is the Coil Pack hope you could stretch to an OEM item?

As an additional I have a Autel Maxiscan MS509 about £65 from Fleabay or contact [email protected] he supplied my unit. They also supply a VAGCOM unit dedicated scanner.

Hope I have been of some help?
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cheers for your help have changed spark plugs and cyl 1 coil pack car has stopped juddering and misfire gone, runs alot better going to dismantle mass flow air meter try clean that up failing that going to change the mass air flow sensor. I got acces to a tester so going to see what comes up again as iv cleared faults for now, have checked pipes cannot find any split also garage checked for these in mot but werent much help at all. many thanks for your help
Have a look on the rosstech web site to see if you can match the codes up... that should give you the general idea of where to look or what to replace.

You should be able to see if the MAF is working using VCDS. Alternatively could unplug it and see if it drives worse or the same. I drove my car 50 miles with the MAF unplugged... i only noticed because i had lower MPG and it wanted to stall if i didnt apply more than usual throttle (i didnt notice that though as my clutch was on its way out at the time).

as for the leaks... they tend to be on the hoses that bend... My N75 hose looks spot on, untill i straightend out the bit that bends and found loads of splits...
whats the n75 hose? i drove other day without attached no diffrence gunna ordr a new one me thinks, iv had a look at hoses but unable to find anything as of yet
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