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[Entwood]

Are they testing emissions correctly if it's running on LPG  

Unless they have a "switchable" tester, or a tester calibrated for LPG (they then have to do a calculation to get the "right" value) they should not be doing the emissions test.

http://www.motuk.co.uk/manual_730.htm

para 7

[Marks DTM Calib]

When you get it on "My Naff Code Reader" Entwood, check the idle block learn values, I bet there at the end of the scale.......

[Entwood]

When you get it on "My Naff Code Reader" Entwood, check the idle block learn values, I bet there at the end of the scale.......

Whats one of them then ....   


Maxscan GS500 here ...  should still read, hopefully, the relevant bits ..  but it's no where near as "all singing" as an "My Naff Code Reader" ..

[Marks DTM Calib]

Ok.

I would expect the idle on petrol to work well after they are rest and probably LPG to be awful.....so a good little test which will prove or rule out the possibility

[Entwood]

Had Keith around today and slapped the reader on ... results are :

Fault codes - engine not running

P0650 - MIL light inop !!!! and confirmed it don't work ..

and a load of transmision faults

P0706
P1740
P1781
P1870
P1890

Started engine and rechecked ....  additional fault

P0141 - O2 sensor heater .... I wonder if that is the cause of the emissions problem ??

Now this is his 2.2 running on petrol not LPG at idle..  Live data, I couldn't find a "block learn" so this is what I got ...

FUELSYS1 - CL
FUELSYS2 - N/A
LOADPCT% - 17.6
ETC C - 70
SHRTFT1% - -0.8
LONGFT1% - 11.7
RPM - 772
VSS 0
IAT - 22
MAF - 2.89
TP % - 2.7
02B1S1 - 0.135 - 0.74
SHRTFTB1S1 - -2.3 - +1.6
O2B1S1 - 0.425

Engine off, Cleared all faults, rechecked .. just the P0650 as expected.

Restart engine and check again

P0650
P0141 - O2 sensor heater

I'll let him take you through the rest of the fails .. but nothing a front suspension rebuild won't cure ... 

HTH the diagnosis by those who understand these things ... 


If it needs more we'll arrange for it to be redone .. but live data on the GS500 is limited to what I've put up ..

A Thought  ... perhaps we should have checked it running on LPG as well ..

[Entwood]

Any thoughts from "them that know" .. ?

[pigtown]

Thanks for the help Nigel.

Another question for the guys out there - The MOT station quoted for replacing 2 lambda sensors but i'm only aware of one on the exhaust after the cat. Is there another? By the way they wanted £400 for the pair fitted!!

[Kevin Wood]

Thanks for the help Nigel.

Another question for the guys out there - The MOT station quoted for replacing 2 lambda sensors but i'm only aware of one on the exhaust after the cat. Is there another? By the way they wanted £400 for the pair fitted!!

There should be one in front of the cat as well. The one after the cat is only there to monitor the cat performance so changing this will certainly be a waste of money. P0141 relates to the heater in the post-cat sensor, so it may have a problem, but it's not what's causing the emissions issue, IMHO.

I can see the long term fuel trim is -11.7% on that live data. More than I would expect but not too alarming.

Is the engine getting up to full working temperature?

I would be inclined to take it for an Italian tune-up on petrol only, then try another emissions check. This time get the print-out and post up the results. Don't run it on LPG. Let's work out if there's a problem on petrol first.

Kevin

[pigtown]

I just checked the post cat sensor and I can't get 12V on any of the wires so wonder if the voltage isn't getting through to the heater. i'm assuming it is a high resistance wire with 12V applied to create heat?
There are 4 wires Black, Grey and 2 white.

Kevin - The car was up to temperature.
I don't have a lot of faith in the original test station so will try somehwere else to check the emissions. Any recommendations in Swindon anyone.

I've had a look at the track rod ends and they are shot - lots of side to side rocking. Is it worth just changing the ends or the whole assembly?

The wishbones seem ok and only one side has any top to bottom rocking but I think that may be wheel bearing.

[pigtown]

Am I right in thinking the post cat lambda sensor heater would be the white wires and it should have 12V permanently on when running?

Also does this one feedback to adjust the fuel mixture and hence the emissions?

[Kevin Wood]

Am I right in thinking the post cat lambda sensor heater would be the white wires and it should have 12V permanently on when running?

Yes, it will be the 2 white wires. They are controlled by the ECU, though, so it's possible it has closed-loop heating of the sensor. It may not apply 12v to these wires permanently. It certainly won't apply anything until the engine's running.

The best bet is to measure the resistance between the two white wires into the sensor with as multimeter on ohms in case the heater is open circuit. 

Also does this one feedback to adjust the fuel mixture and hence the emissions?

No. This sensor is only used to check that the cat is working. The front (pre-cat) sensor is used for mixture control. The post-cat sensor has no effect on the emissions or engine running. Hence my thoughts that the main problem is elsewhere.

Kevin

[pigtown]

The 2 white wires into the sensor measure 5.5Mohms.
That's pretty high so I'm thinking the sensor heater is dead. Anyone got one to measure and confirm?

Is the pre cat sensor accessed from under the car or though the engine bay? tried a quick look and couldn't see it, although it is dark out there!

[Kevin Wood]

The 2 white wires into the sensor measure 5.5Mohms.
That's pretty high so I'm thinking the sensor heater is dead. Anyone got one to measure and confirm? :-/

Is the pre cat sensor accessed from under the car or though the engine bay? tried a quick look and couldn't see it, although it is dark out there!

I don't know for sure for the 2.2 sensors but typically would expect to see 10-15 ohms. 5.5M is an open circuit for all practical purposes so that explains the trouble code (but not the emissions problem, I'd say ).

As for the pre-cat sensor it'll be right up on the downpipe or even the exhaust manifold. Probably still best accessed from the underside though.

Kevin

[pigtown]

FYI - got a new lambda sensor and the heater circuit measures 5 Ohm. Will fit at the weekend.

[Kevin Wood]

FYI - got a new lambda sensor and the heater circuit measures 5 Ohm. Will fit at the weekend.

OK. If that doesn't cure it try swapping the new sensor with the pre-cat sensor so the new one is pre-cat and the old one post-cat.

Kevin