warning lamp

[neo64]

Hi all

I have a 4.2L EFI GQ patrol and a warning light has come on that I am not sure
of. The Light is orange and sits in the tacho guage area, it is a round orange
light with a horizontal dotted line through the centre and an arrow pointing
downwards. Forgive my ignorance but what is this telling me.

Thanks

[Bigrig]

Hey mate - as said in the intro post, if it's in the dash cluster, sort of just off centre in the tacho area, then more than likely the air filter warning lamp - appreciate you said the filter had been replaced, but not sure if the sensor detects for anything else other than just a clogged filter etc.

I've seen this on here before, so I'll have a hunt and see if I can find the thread - no doubt someone else will be along shortly to assist anyway.

[Clunk]

is the light on constantly or does it only come on under acceleration? If it's the latter I think it's the air filter warning light - it may be a little full of dust

[neo64]

The light does go off after acceleration but takes a while, I might clean the area and filter tomorrow and see how that goes, I am
also wondering how the blocked filter is detected? is there a sensor in the housing somewhere?

[the evil twin]

Another vote for the Air Filter Differential Pressure Warning

[Clunk]

there's a little sensor that sits on top of the large pipe that runs from the airfilter box............ sorry I'm not technical, so don't know the terminology, just becareful when removing the top cover though coz the sensor is easliy damaged apparently.

[neo64]

Thanks....I will tackle that with zest tomorrow.

[Bigrig]

there's a little sensor that sits on top of the large pipe that runs from the airfilter box............ sorry I'm not technical, so don't know the terminology, just becareful when removing the top cover though coz the sensor is easliy damaged apparently.

The inlet ducting is the big pipe that runs from the top half of the air box. The square sensor is the Mass Air Flow sensor, and not sure if this warning light is connected to that sensor though - Tony and crew can shed more light on that one. If the MAF was dirty/malfunctioning, you would more than likely notice it in performance - i.e. The truck would potentially run rough, over or under fuel, etc.

As said, others will be along with far more knowledge than me to guide you through it.

[the evil twin]

there's a little sensor that sits on top of the large pipe that runs from the airfilter box............ sorry I'm not technical, so don't know the terminology, just becareful when removing the top cover though coz the sensor is easliy damaged apparently.

I think thats the MAF your talking about isn't it, Square Cover held in screws ? If not, my bad, sorry

The Air Filter Switch has small dia rubber tubing going to it and (from memory) is below and behind the Air Inlet Pipe. Been sooooo long since I played with one. God I feel bad I loved my EFI GQ and the memory is fading already

Where's Todd with a Piccy ?

[YNOT]

The way you've been answering technical questions lately Scott, I'm starting to feel redundent!

The air filter clog sensor is mounted near the air box and has 2 small vacuum lines coming off it. One hose runs to the the top housing above the filter and the other to the bottom housing. When the sensor detects a lower pressure above the filter (indicated a blocked filter) it switches on the warning light.

Tony