Mystery knob (not me)

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Swanny
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Mystery knob (not me)

Post by Swanny » Wed Jul 15, 2015 1:50 pm

Ok, I've asked a few stupid questions on this forum, but I'm genuinely stumped by a random knob in the passenger footwell on the trim panel under the glove box. I was looking to see what colour ECU I had but found this puzzler instead. Any ideas? I've done a quick search of past threads but to no avail.

Swanny
480 Turbo S/R 'Matilda' - '89 red - Norfolk

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glasgowjim
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Re: Mystery knob (not me)

Post by glasgowjim » Wed Jul 15, 2015 2:52 pm

should not be a switch there at all :D

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Slash01
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Re: Mystery knob (not me)

Post by Slash01 » Wed Jul 15, 2015 3:13 pm

Would it be by any chance one of the 3 push fittings for the tray that fits under the dash in that area?
There are always ample warnings and there are always subtle signs,
And you would have seen them coming but we gave you too much time.

Swanny
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Re: Mystery knob (not me)

Post by Swanny » Wed Jul 15, 2015 3:50 pm

It's definitely a potentiometer, I can see the back part of it, I'll post pics later. I always thought it was a push fitting of some sort, but it has an arrow on it and it turns through about 270 degrees. Should I be excited? I'm just not convinced the old bloke who had the car previously would have had it modified, but I did buy it through a "dealer" (some bloke who bought it off garage after it was traded in). It doesn't have "Go baby go!" written next to it sadly :cry:
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Swanny
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Re: Mystery knob (not me)

Post by Swanny » Wed Jul 15, 2015 5:47 pm

Ok, tried turning it and disconnecting battery for 30 secs, did nothing as far as i can tell, am i missing something? And I know I'm being dumb, but where the hell is the ecu? HBOL says in side of pass footwell, not that I can see
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Re: Mystery knob (not me)

Post by glasgowjim » Wed Jul 15, 2015 6:20 pm

assuming you have a right hand drive car (uk) ...

sitting in the drivers seat the boost ecu is in the centre console just above your left ankle . just l9ft up the centre console flap its velcroed on at the bottom and you will see it . The engine ecu is directly across from it to the right hand side of your right ankle behind the trim panel but up a bit closer to the dash board.

Swanny
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Re: Mystery knob (not me)

Post by Swanny » Sat Jul 18, 2015 11:46 am

Ok, the saga continues... I pulled my ECU out today to have a look at it, I thought I'd have a look at the screws based on my new-found knowledge about richmod identification, and it turns out there's been a bloody richnod fitted for the past year without me knowing! The mystery knob turned out to be a thermostat from poland (?), i tried turning it up and disconnecting battery for 20 mins, took it for a drive, didnt feel too different, so now ive turned the stat the other way and ill take it for a spin later. Do any of thw experts on here know how the hell you would control boost with a thermostat? What kind of 0 to 60 should I be getting and turbo gauge pressure? Thanks.
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Re: Mystery knob (not me)

Post by glasgowjim » Sat Jul 18, 2015 1:26 pm

if it is a richmod or a robou mod there is no thermostat controller.

The only thing that would have a control dial would be a manual boost controller and thats not electric.

put up a photo .

This has absolutely nothing to do do with the boost of the engine.

Follow the wires back it oh and have a look at the wires are they colour coded similar to the genuine volvo wiring ? If not then it is something that has been added by a previous owner.

Just disconnect the potentiometer and see what happens - I expect it will be absolutely nothing.

Swanny
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Re: Mystery knob (not me)

Post by Swanny » Sat Jul 18, 2015 2:11 pm

So is it likely that the richmod was working the whole time? Ive driven the car so much its just normal for me but i dont think its got the 170bhp that it would with a richmod.
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Swanny
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Re: Mystery knob (not me)

Post by Swanny » Sat Jul 18, 2015 2:33 pm

Image
Image
Last edited by Swanny on Sat Jul 18, 2015 3:35 pm, edited 1 time in total.
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Swanny
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Re: Mystery knob (not me)

Post by Swanny » Sat Jul 18, 2015 2:39 pm

Can anyone see those pictures I posted? First time posting pics. Wires are green/yellow and green I think.
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Re: Mystery knob (not me)

Post by glasgowjim » Sat Jul 18, 2015 3:02 pm

No go to photobucket or similar access your picture and copy the img address and post it into your thread.

Swanny
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Re: Mystery knob (not me)

Post by Swanny » Sat Jul 18, 2015 3:27 pm

Thats what i did, ill try again
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Swanny
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Re: Mystery knob (not me)

Post by Swanny » Sat Jul 18, 2015 3:36 pm

Sussed it, see above
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Re: Mystery knob (not me)

Post by glasgowjim » Sat Jul 18, 2015 3:42 pm

Definately not standard havent a clue you do need to follow the wires back

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Van
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Re: Mystery knob (not me)

Post by Van » Sat Jul 18, 2015 9:32 pm

Yeah the foam looks cut out.
Maybe a diy headlamp height regulator?
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doingitsideways
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Re: Mystery knob (not me)

Post by doingitsideways » Sun Jul 19, 2015 10:09 am

Most likely had a big sub in the boot at some point, this knob probably controlled how much the rear view mirror vibrated ;)
"If you can't fix it with a hammer, it's an electrical fault!"
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Swanny
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Re: Mystery knob (not me)

Post by Swanny » Sun Jul 19, 2015 6:49 pm

Ok, the knob turned out to be a thermostat connected to the aircon. I revved it to 2000rpm, then turned the stat knob, without moving my foot the revs jumped about 500rpm. I don't know why someone wold do this but the car is normally undriveable when aircon is running. I cracked open my ECU and took a picture, I can't see anything obvious but i wouldn't know. Image
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doingitsideways
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Re: Mystery knob (not me)

Post by doingitsideways » Sun Jul 19, 2015 9:58 pm

Hmm... Bizarre!

Has the A/C been added since production?

Pretty sure the revs are supposed to be raised automatically when the A/C is switched on.
"If you can't fix it with a hammer, it's an electrical fault!"
Hammers can't fix a 480!!!

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