Thread: TD5 and Nanocom

Intake air temp should be the same temp as ambient temp of the engine bay.

Are you getting any fault codes present or logged?

Sluggish cold starts are more likely to be from a poor connection in the starting circuit
Or a battery issue. The reduction gear starters fitted to these either work or they don't!

No fault codes but intake temp can be 20deg+ above ambient after only 10minutes running.

Have you done anything on the fuel system lately? If its misfiring and not logging any faults it could be due the fuel system not holding pressure and leaking back down between starts?

Is it similar symptoms to air in the fuel system?

Nothing done to the fuel system and it only happens rarely on a cold start and runs fine after initial blip of the throttle. Coolant temp sensor seems accurate so leaning towards intake air temp as its a lot different to ambient. Vehicle fitted with a snorkel so wouldn't have thought it would be to different. Glow plugs changed today as well.
I dont think its leaking back through the injectors as it fires instantly and normally if its leaking injectors you have to crank for awhile to build up the fuel pressure I think??

Log the readings and or look at the nanocom in instrument mode. Specifically check the cylinder balance readings, they will move around a bit but should not go beyond a reading of +\- six (IIRC). Anyway, regardless of actual value if you have a misfire you should be able to see on which cylinder by looking at the readings, they will look odd compared with the others.

And ambient temp of the engine bay is not the same as ambient temp. Just go for a drive then hold the inlet manifold and you'll see what I mean, it does get warm. My ambient temp reading is always reasonably higher than the ambient air temperature but never had a problem, it surprises me how much, especially since its gone through the intercooler prior to passing the sensor, +20 deg sounds reasonable to me. Regardless I couldn't see a bad inlet temp reading giving you a symptom like you describe, after all it should start smooth at a range of ambient temps, mine has from -10 to +50 degrees. You could always pull the sensor out and give it a wipe, if you still have an EGR or have had one, it can get pretty gacked up.

Ian.

Have you recently changed the fuel map?
I have had certain maps that do exactly what you are saying