Freelander 1 TD4 MAF Diagnosis - tips

Still trying to diagnose my 125k mile TD4 with odd poor starts (not really a pattern) but cold mostly worse. Bit of mis-fire type symptoms at tickover and bit 'tappy' compared to others.

So - thought I'd share this, took my faithful 185k mile TD4 which has never missed a beat, put it on my icarsoft diagnosis machine. Listed all live data from cold. Did same with the dodgy car. What showed up was the inlet air temp was massively different (12 deg on working car 26 deg on faulty car) and the Airflow - 500 - 600 mg/stroke on working car and fluctuating 360 - 560 on faulty car).

So - have ordered a new MAF as I think this does both sensings??

Thought I'd share it, have also got all other live data from a good working TD4 if anyone needs comparisons.

Is the EGR valve stuck open on the bad running car? This could account for the out of spec data.

Good thinking, but it shows air temp of over 26 deg C whilst engine is off and ignition only is on. Figured this must be a sensor issue?? Also - does the EGR cooler not cool the air / exhaust at intake?

So - have ordered a new MAF as I think this does both sensings??

Click to expand...

on models prior to ones with the separate A.I.T. Temp. sensor on the top intercooler hose ..
part of the maf sensor circuitry takes care of that reading

as for exhaust gas cooling for the egr valve
auto gearbox models have a cooler fed with engine coolant
manual gearbox models don't ..

( a.f.a.i.k. )

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