High emmissions

[ukhozi]

Corsa B 1995 C14SE engine, 1.4 Sport.
Failed MoT (ITV) on high emissions and also has high fuel consumption.
Replace recently ALL sensors, TPS, AFS, ICV, Oxy sensor, plugs, (twin points) and OEM HT module and leads/caps
Head recently skimmed after gasket blew between 3 & 4 cyl, all new gaskets and seals of course inc new head bolts.
(First guy who even thinks EGR is fired, you should know that this model doesn't have one. )

I have checked for loose connections and have removed the in-line three way plug on the ICV as per GM instructions.

Not getting any lights on.

I have read elsewhere on here that changing the CAT and Lambda will probably NOT cure it and is probably a sensor/ECU problem, seem to be lots of THEORIES about but I am hoping someone can give a definitive answer based on experience..

Readings were.
CO 7.82%
CO acceleration 12.15%
Lambda 0.685
Opac m1 9.2

Car starts abd runs well, in fact it goes like stink!

Wife says when she drives it the tick over goes very high for quite a while but I don't seem to have the same problem.
So, anyone able to put a finger on this one?

[johnny]

Whats the fail level for the icv? Is it icv? What's the fail level for the Spanish test lol

[ukhozi]

IVC = Idle Control Valve,, Black roundish thingy on the throttle body.

Test levels are the same as UK. Euro standard. Main difference is they can only be done at a regional ITV (Inspection Technical Vehicular, (in English)) centre not at Joe Blogg's garage down the road, I'm lucky as they have just opened a nice shiny new 5 lane one instead of having to drive 50 miles to Malaga as before but they are a bit keen.

CO2 should read 158 G/KM
and 6.8l/100Km or 35MPG, but using at least 50% more than that, lucky to see 11L/100 , 20MPG
so now we have that sorted, do you have any firm ideas?

[johnny]

I'd change lambda, try an engine flush as well to clean All the gunk out, if it's not a sensor issue then it's either cat or gunked up engine

Do you have terra clean in Spain?

[ukhozi]

Fresh oil and filter, engine was cleaned inside and out when I skimmed the head, (check valves, new stem seals, etc) Lambda is less than two years old but a 'maybe'. Cat is original as far as I can see but that wouldn't address the higher than normal millage fuel consumption would it? Plug colour is 'normal' light tan.

[johnny]

Get a new cat for it and before the test give the car a thrashing, the hotter you get it the better the emissions will be

[ukhozi]

Managed to get the car for more than a few minuets and found a load of faults, indicator not working, the reverse lights and cigarette lighter circuit dead but fuse OK, half the dash bulbs naff and plug lead end loose (just pulled off and stayed on the plugs when I took the caps off) on #1 & #3 and needed re--crimping, so OK now,
Cleaned the lambda sensor plugs, (oily), fixed indicator (cruddy connection) and still scratching my bonce on the reversing lights BUT managed to do a paper clip test at last and....

Normal code 12 start up code

Code 17, there is no code 17??
Code 22 Throttle Position Sensor, voltage too low, so that's adjust the throttle stop screw, again
Code 44 Lambda sensor (too weak), that's weird.

Anyway to check the cat without buying a new front pipe/cat?

[johnny]

Some garages can test for a dud cat but most just test be testing the temps each side of the cat as if it's blocked it'll be colder after the cat but that doesnt Test the actual baffle thing in the cat

[ukhozi]

Code 17 was actually code 71, Air temp sensor voltage and code 44 has gone after I stripped and cleaned the oil out of the single pin connector for the Lambda.
Checked CAT and it seems OK, as the garage guy said, none CAT versions don't have as high emissions as mine does.
Changed the throttle position sensor and found the little piece that fits in the slot of the throttle spindle was missing, so as it's a none purchasable part, at least I can't find an EPM with it showing, I made one from a bit of scrap plastic 10x6x2mm. I still get 22 and 71 but I have a new ATS now and just need to get the car back of the wife so I can fit it, but I can't seem to get rid of code 22, TPS voltage too high, I have checked the earth, 5V and ref voltage and they seem OK. is there a method of adjusting the butterfly stop screw? I have screwed it right out so it doesn't touch to 4mm in with no change. Do I need to disconnect the Idle control valve and TPS to set the 'tick over' speed first?.

[ukhozi]

yeah! cleared code 71 with the new air temp sensor, now it is down to code 22, 'throttle position sensor voltage too HIGH.
New TPS but still reading too high. new 'blade' in the throttle shaft is a good fit and seems to be working but I have adjusted the stop screw on the butterfly from just touching to 4mm uo and still code 22 comes up, is there a starting point such as a clearance between butterfly and body as on DellOrto set up or a reading on the return voltage I should be looking at, I can't seem to find anything relevant and my online manual is in German.

By the way Johnny, my ancestral family come from county Donegal, the Lee family. Apparently, according to my late father, a great, great, great uncle of mine was hung for steeling a pig, some claim to fame eh?

[johnny]

I've never heard of anyone replacing the the butterfly valve as its cheap to replace the whole thing here so tbh I can't help as I'd only be guessing

[ukhozi]

Wasn't really planing on replacing the butterfly, rather needed to know what fits in the slot of the spindle.
Up date;

Been playing with the TPS and both old and new ones work but the two pips inside are at different positions, I can get the required 0.42V on the blue wire, (ECU ref voltage) and I have 5v and ground but at 1/3rd throttle or the TPS is 10mm from the mounting holes, on the old one it is less, about 15 degrees but still too low. is the bit that fits in the spindle slot just a bar or is it more complex than that?

[johnny]

Wasn't really planing on replacing the butterfly, rather needed to know what fits in the slot of the spindle.
Up date;

Been playing with the TPS and both old and new ones work but the two pips inside are at different positions, I can get the required 0.42V on the blue wire, (ECU ref voltage) and I have 5v and ground but at 1/3rd throttle or the TPS is 10mm from the mounting holes, on the old one it is less, about 15 degrees but still too low. is the bit that fits in the spindle slot just a bar or is it more complex than that?

Aw ok sorry I read it wrong

On the tps honestly I've never looked at one that close mate it's usually just a case of replacing them

Can you get op com? It has a really nice feature of live data so you can plug it in and while driving watch what everything is doing/ not doing

[ukhozi]

I have an Autosnap but it will not read J1962 10 pin only 12 pin or ODB2,

I think that although the seller says it is for the C14SE it is wrong. If I make an insert so that the internal part is rotated 20 degrees or so (preloaded) so I get 0.42v at rest it is then wound around too far and hits the internal stop before WOT as it only has about 110 degrees of travel. When I manually turned the inside of the TPS off the car I get the 0.42v (and boy is it sensitive), the engine responded accordingly to the slightest touch so I am sure the ECU and wiring is AOK, I am going to 'T' an additional blue wire to a terminal end so I can attach the multi meter to the ref wire without having to hack into the wires cover.
Just need to get the lowdown on the 'interface' part and the correct sensor or alter the internals of the one I bought now I know it works.

[ukhozi]

Managed to blag a complete C14SE throttle body from Ebay Israel of all places and only 18 pounds too INC POSTAGE. So week or so and should have it sorted, just hope the emissions come good.