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VQ25det A/F Learn 82%

DodoStag
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DodoStag Rookie

DodoStag

Posted
Posted

Hey guys i need some advice/ help from the incredible brains of the import community please.

Ive got a 2003 Stagea VQ25DET and ive got an HKS OB-Link connected. My problem is lack of power, lack of boost (gauge hows 7-8?psi max) and a rough idle and if left to idle for a few minutes will stall...

Sitting idling the ob-link shows this20200606_123724.thumb.jpg.aaf86aa50e1e939a7092e30bbbf8a573.jpg20200606_123808.thumb.jpg.600ecc8ba8760d1aac20134d0d33502e.jpg

sorry for the hazy photos the glass on my cameras broken...

Its also has the fault codes P0100 and P0235.

Ive replcaed the AFM twice and had the codes cleared by a mechanic but has returned...

When it idles rough or stalls theres a strong smells of fuel coming from the car.

Also the exhaust seems to sound like theres a hole in in the exhaust but the sound isnt there all the time its intermittent...

Dont know if this is related at all but the fuel gauge doesnt show the correct fuel level..  

First off what does the 82% a/f learn mean plz???? Oh and that figure does not change!!! Idling or under load its always 82%

Any and all help would mean the world to me ive only had the car 6 weeks and still dont know what its like to drive a healthy M35 stag....

 

 

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https://www.sau.com.au/forums/topic/480552-vq25det-af-learn-82/
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KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

Please turn the photo round the right way.I am looking at my desktop and cannot easily turn the screen.

So far as I can tell that device is only reading the information that is in your ecu so if you do not have a wide band sensor it will not have any useful information about your AFRs.

So forget the device and go back to basics. Check your plugs, coils and look for boost leaks (as in test for boost leaks - they are not always easy to spot).

robbo_rb180 Grand Master

robbo_rb180

Posted
Posted

get hold of a scan tool or obd reader and actually check what the sensors are doing if voltage is stable or random. Bet it will be a failed O2 sensor and a leak near the cat giving odd readings.
An old thread for connecting to M35s
https://www.sau.com.au/forums/topic/280322-m35-obd2-or-is-it/page/3/

MrStabby Grand Master

MrStabby

Posted
Posted

Check for loose / leaky hoses, in particular the ones to the fuel pressure regulators. When they've hardened a bit with age the boost can blow them off. In mine, the fuel trims maxed out when i had leaks. If you can measure vac at idle, i'll check mine so you can compare.

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