Volvo 480 Club Europe

CO at idle was high at MoT, but just squeaked through .. .

so I got a loan of an old GUNSON CO meter but it's puffer has puffed its last and can't see an easy way to fix it.

so silly question, can I use a LAMBDA sensor as an alternative?

I know what the voltage should be for each ratio ie from 0.2V to 0.8V

so the thought is to buy a new sensor (£8 or £9) and wire it up complete with the heater element and an extra wire for the 'earth' then it should show me if any changes i make are having the desired effect, les worried about the 'actual figure' just if going 'right way', and anywaya a lambda sensor is not going to go wrong? ? ?

HBOL suggests removal of lambda and disconnect battery for a short time before starting car so the car goes to a 'limp-mode' and then screw in a CO sensor into the hole where lambda came out of. it suggests can't do much to adjust the CO other than check the items below


I wonder about
a dribbling injector ?
emissions from petrol tank valve staying open when it should be closed at at idle?
missfires
temperature sender of block for ECU not working?

other options are possible and willing to listen

Alan 480 wrote: ↑

Thu Mar 12, 2020 7:10 pm

CO at idle was high at MoT, but just squeaked through .. .

What were the HC values?

Jeff

Full results:-
Fast Idle
CO 0.06%
HC 10ppm
Lamda 1.02

Natural Idle
CO 0.01%

Limits
Fast idle 2500 - 3000rpm
CO 0.2%
HC 200ppm
Lambda 0.97 - 1.03

Idle 450 - 1500
CO 0.3%

The HC is first and breezed it,
next test was Lamda started well high 1.3?
natural idle , couple of attempts , sat at 2500-3000rpm for a few minutes and let it return to idle and tried twice?


so although looks well under it wasn't just a simple run through.

air temperature at the time was 2-3 above zero, so ruddy cold . . . .

PS remembered that I have a used Lambda sensor, i thought it was slow reacting so changed it.
so nothing to be lost by trying it in one/all of the fleet SS1, 480 x 2, C30

Any thoughts about easy way to check if the injectors are 'bubble-tight'?

The first thought was to make a small jig to hold the injector and supply fuel via a small pressurised tank, but that might be more hassle...
the tank would just be a section of 1/2" BSP plumbing, half filled with petrol and supply pressure via the air line, suitably regulated

I thought about removing the whole injectors assembly and turn on ignition, but not try and start, so that the system is primed and if an injector is 'dribbling' then I'd see it.

I still reckon it smells a little rich, on idle, but bought a NOS lambda to see if that helps, just covering bases before the MoT in early February.

if push really came to shove I'mm sure I could do a VW 'bypass'

Hey Alan. If you want them tested and cleaned, then I can recommend injectortune.co.uk who will do a shut-off leak check as well as the spray pattern after cleaning-- all done by post and PayPal. I've done two 480 injectors and one had noticibly smoother idle (the old E-reg) after returning; I've also do my C70 and Avantime with them.

jamescarruthers wrote: ↑

Tue Dec 29, 2020 5:28 pm

Hey Alan. If you want them tested and cleaned, then I can recommend injectortune.co.uk who will do a shut-off leak check as well as the spray pattern after cleaning-- all done by post and PayPal. I've done two 480 injectors and one had noticibly smoother idle (the old E-reg) after returning; I've also do my C70 and Avantime with them.

OK, might be better to send the set from the spare cylinder head, if i can find the fourth one, I took one out 'as a spare' and cannot remember where I put it for 'safe keeping' maybe in the boot of the red one as had a lot of spares there, eg coil, plugs, rotor arm etc

bought a generic lamda sensor (DELPHI same as into EVA previously, so should be OK) and fitted that today, fingers so ruddy numbhad to come in twice to thaw out
when removed the 'BOSCH' item it had an 'oversize' plastic washer that was only seated around 3/4 of the face, maybe this was letting in 'fresh air' and diluting the reading so the ECU would turn up the mixture, MoT time will be the telling point . . . .

If you want to know what your engine is doing then you need a wideband.

I have the AEM model. You do not need after market ecu but it will output if you do. I can tell if my 940 is running well or not just by looking at the AFR. For the money it's a steal. I think it outputs the narrow band in emulation but personally I brazed a o2 bung on my stainless downpipe 18" down from the turbo so it's seperate. Best gauge I fitted over the years. You don't need a turbo car either.

https://www.t7design.co.uk/catalog/prod ... r-30-0300/

MoT for another year.

still 1.03 Lambda

but commented that 'emissions was better than last year'

I still think it 'smells' rich when idling which is 'wrong', cos a high Lambda is 'lean'? happy to be told wrong!

looking at ALL previous MoT the trend is to show a high Lambda , might be the ECU?

but can't do any adjustment.....

FULL Results
Fast Idle
CO 0.15%
HC 30ppm
Lamda 1.02

Natural Idle
CO 0.15%

Limits
Fast idle 2500 - 3000rpm
CO 0.2%
HC 200ppm
Lambda 0.97 - 1.03

Idle 450 - 1500
CO 0.3%