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Possible MAF problem - need help understanding diagnostics

Hi all,

My GTV TS suffers from intermittent idle hunting. Having just got a lead and diagnostics software, I'm not seeing any error codes, but what I am seeing is the O2 sensor reading fluctuating madly and the fuel mixture oscillating between Rich and Lean. I have little knowledge or ability when it comes to such things; is this what you would expect to see with a faulty MAF? I'm reticent to fork out for a new one without some confirmation that it is the likely culprit. Btw, I've checked the hoses and they seem sound.

Thanks in advance!
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I'm not an expert in diagnostic but all I know is when my MAF sensor was dead, the diag was showing 0 for the quantity of air going in the engine. So if you see 0 with the engine running or maybe in your case weird oscillating values even if the engine is @ idle, it could be that but I'm not 100% sure
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Hmm, not the number of responses I had hoped for! Just to add a bit more information in a not so subtle attempt to bump the thread, it's the O2 sensor voltage reading I'm talking about and it fluctuates wildly between about 50mv - 800mv. Is this normal? It's a bit of a downer to have got the diagnostic software (FIATECUSCAN16) working, but then not to understand what it is telling me. I was hoping for some obvious errors. On a related note, when the idle does steady for any length of time, a nudge of the steering or turning the blowers on, causes it to fluctuate again! Sounds weird but no doubt you expert types will hopefully make sense of it.
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Forgive me for talking to myself but I'm starting to learn something that maybe useful.

After a bit more research on O2 sensors it appears that they do fluctuate as the...

"more oxygen in the exhaust (lean condition) the lower the voltage from the O2 sensor and the more fuel the computer calls for. Then the oxygen content in the exhaust drops (because it is being used up in the combustion process), and the voltage increases (rich condition) and the process repeats, for as long as the car is running, hundreds of times a minute" (quote from Diagnose Check Engine Light Codes, Emissions And Oxygen Sensor Faults)

So it seems I'm no closer to diagnosing the idle problems. Guess the next step is to fork out some money for a new MAF in the hope that will cure it.

Unless anyone else has any ideas?
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I would be tempted to try a new water temp sensor before you start forking out money on a new MAF but as their are no fault codes, I would get the old carb cleaner out and clean up all your intake areas.
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I had the same problem with mine and i've just had the lambda sensor replaced but that was picked up with diagnostic
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GTV 3.0 V6 24v

Hi, I have a similar issue and spoke to a good indie the other day, they recommend testing your maf by leaving it plugged in but detatching the pipework. You then blow into the maf and as it is heat sensitive, the engine should respond accordingly and as the mixture changes the smell of the exhaust fumes will change with richness/weakness.

I haven't tried this yet but will tomorrow if it's not chucking it down. Until I get my hands on some diagnostic kit this is all I have to go on.

Another possible cause, so I am told, is the throttle potentiometer. If it's buggered it will idle all over the shop, if this is the cause then you have replace the throttle body as it's a sealed unit. Simple job as it's only held on with 4 torx bolts. Apparently £600 odd new but s/h for £30 or so.

Apparently lambda probe can cause similar idle trouble. Good luck with it, hope it's not a head ache
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