The injectors should open and close normally, but as Cody says, every engine type react differently to low fuel pressure. My Volvo delivers fuel pretty linear to pump voltage, but with the Mazda I can adjust 10-20 % fuel pressure and then nothing happens until almost full voltage. Only one way to find out.
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Hey JanA your too high of CO readings means either lack of oxygen or lack of the conditions to completely combust to CO2.
Here Washington State as a certified Auto Emissions Repairman we used four gas analyzers to repair. The fourth gas was exhaust remaining oxygen. Have a 2-3-4% exhaust oxegen then the focus would be on conditions. Engine compression. How active and hot the cat is getting.
High CO and the exhaust oxygen is zeroed out then the focus has to be on getting more oxygen for the converting. Air cleaner; air induction; dual-bed cat pumped air supply; the cats ability to store and hold oxides; the EFI cycling the engine rich-lean, rich-lean to load oxygen load up the cat.
So try these:
get that cat worked heated up to smoking hot before the test.
Dab an end of a rag into new motor oil. Dab that onto the underside cat shell. WHEN you get that Cat hot enough to smoke the oil âsmoking hotâ you will have maximum cat performance.
Here WA State testing was done at separate contract agencies. Hot cat, avoid days, time with lines. IGNORE their signs saying to shut off the engine while waiting. Keep it running with the rpm held up at least to 1500-2000.
Yep. Iâve been booted out for that. Go back a different day into a different line with a different inspector. That cat MUST be HOT and kept HOT.
2nd trick for slightly high CO is to add an oxygenate to the fuel. Not too much. Or you will create misfiring driving up your HCâs.
The attitude of the repairman and the inspector is super important. Our laws and regulations here were actually to get old pee-loot-er vehicles retired off the road.
Me as a repairman and some inspectors the goal is to help people out, not to sell new carsâŠ
S.U.
Oh I should add nowâs the time you want a HOT coolant. Radiator block to get that. Not illegal.
.
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Steve, it is nice to have some one who has done the emissions tech. inspecting work and knows all the tricks to make in through a inspection. I am glad we never had inspection on this side of the mountains. Have they completely stopped with them over there where you live now?
Bob
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Hi Jan, have you tried the old inspection trick with 4 bottles of âkarburatorspritâ in 1/4 to 1/2 tank of gasoline?
This was a good trick for carburetted engines, as SteveU says it brings oxygen to the process.
Karburatorsprit=99% ethyl/isopropyl alcohol used to get rid of water in fuel tanks, was very common to use in Sweden, wintertime to get rid of any condensation that use to collect in carb float bowl.
This is a very old inspection cheating, some also used windshield washer fluid, or mix 50/50% gasoline/e85. Observe! To much of e85, k-sprit, methanol or what ever you use can give the opposite (personal experience)
I once had a -64 Buick Skylark that didnât pass the inspection due to 8,5 co at idle, (limit: 4,5, older cars) i did some of the above mentioned tricks that bring the co down to 0,2 
the inspection guy give an âevil eyeâ when he almost not could get the car over the "brake-test-rollâs, a lot of backfiring, stalling, and powerful detonations in the air-cleaner.
This car got a carb overhaul later, but when youâre young and want to hit the roadâŠ
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BobMac Washington State physical inspections mandate ended as of January 2020.
https://www.king5.com/article/news/local/emmisions-testing-in-wa-comes-to-an-end-after-38-years.
The âneedâ as mandated by the Federal EPA justification was no longer valid.
However most connectable later model vehicles ( the Wifeâs 2014 Ford Edge) can be remotely commanded to cough up with their OBDII status and data driving. Just like your smart electric meters; the truckers scale high speed drive thruâs; the bridges toll stations.
So a potential next-step when they want.
Just like
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Yes, I have thought about k liquor too. Also think about what you said about the heat, wondering if the heat in the engine is too low, so the computer sends out more petrol (60 degrees c after the meter (140f)). Will check with obd2, and maybe change the thermostat and air filter, the air filter can get a little gas when start.
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I ested with the obd2 plug this morning, 78 degrees c (172f) so the heat should be enough.
Had it on so I saw the ignition also, around -27 degrees it seems to adjust to.
No. JanA. Your coolant temperature is not hot enough for least exhaust emissions on gasoline.
You want it cycling 212-220F. 100-105C cycling.
Steve Unruh
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Hmm, I usually buy thermostats that open at 180f, the only one that rock auto has, opens at 192f.
Do you think that is the whole fault?
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Jan I think your thermostat is set too cool. I would only want a 180F one if I lived in a very hot climate. GM engines like to run a little hot, I think the one for my 1996 Cavalier is 190 or 195F I canât remember exactly.
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@SteveUnruh I did some reading on the exhaust values, it says that if the lambda value is above 1, then it is excess air.
How can it then be too high CO, which then means that there is not enough air?
Is it the catalytic converter that is bad?
Maybe an underactive catalytic converter JanA.
Verify itâs basic functioning by itâs ability under a high flow hard engine loading to get very hot.
No hotter then the piping before and after then it is indeed active material, dead.
Excessive exhaust oxygen could also mean that the oxygen was not fully utilized up inside the engine. Your too cool of coolant. Ignition timing. Low engine compression. A few other in-engine possibilities.
Excessive exhaust oxygen can also mean an exhaust system air leak after the engine too. Accidental. Intentional.
Here they do not test by exhaust Lamba. But by the combined percentages of measured exhaust CO2 and CO. It must be above 11%. Later years with their in-pipe testing they also watched directly for excessive unused exhaust O2. Theses two values wrong and you failed.
And in Washington and Oregon states vehicles manufactured after 2009 they totally rely on testing the OBDIIâs computers functioning, stored codes and memory time/mileages since the codes were cleared and reset.
There were many levels of advancement to OBDII systems self-diagnosis and disabling capability. Most all systems by 2009 as Throttle-By(electrical)-Wire then; and they can really have you by the short hairs.
The eight different programed computer monitors see wrong too long and it will take away your engine power and your transmission gears forcing you into limp-home mode. Forced too long Limping and you will be stopped by the computer. Call a tow truck to a shop.
S.U.
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Thanks Steve. That was a good idea, Iâve ordered a new thermostat, letâs see if that helps.
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@JO_Olsson I discussed pwm with Niklas, thinking about testing it, see if it works.
How do you have yours connected, do you run through pwm all the time, or do you have a by-pass line to the pump?
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Jan, I use no by-pass. The knob has to be all the way on to run 100% gasoline. 98% of the time the main pump switch is off anyway 
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Ok,so you have a contact on + cable to the pump before pwm?
How much do you usually have on pwm, on the uphills? Are you completely fine now from the covid?
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Yes, a sparate on/off switch in series is necessary, because the PWM doesnât shut the voltage down completly. And yes, the switch is on the + side of the PWM.
Any setting is possible. Depends on the extra power needed. The more you open the air-mix, the more fuel you have to add.
Most of the time I donât hybrid at all, but in an open road situation pulling a trailer up a hill and traffic behind, I sometimes turn the PWM fully on with the air-mix fully open. The motor will still pull a few inches on the gasifier and will probably run slightly rich. But, as soon as Iâm on top of the hill, I turn the main switch off and adjust the air-mix back to the normal woodgas setting. In a situation like that I wouldnât even need the PWM. Only the switch.
For the most part I use the PWM only to add a few drops, for a few seconds, when the gasifier still isnât up to temp - pullstarting.
No, not yet. Still a slight fever.
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Ok, so then itâs better that I learn to turn on the fuel pump without the car stopping on the hills, not necessary with pwm.
With the air-mix fully open it should have no problem accepting 100% fuel pressure. With a steady throttle you can even experiment slowly closing the air-mix. If youâre lucky the oxygen sensor will notice this and tell the computer to cut down on fuel automaticly. But all this is hard to tell, because every system reacts differently.
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