Bad on gas emissions - HC, CO, CO2 - with new Qudrajet

[gbody79malibu]

Hi guys,
I had changed my Quadrajet against a new one and have been in some troubles since then. The old carb was worn and I could never get it qorking quite well. So I replaced with it with a remanufactured (by SMI) Quadrajet of the same M4ME style on my 79 Chevy Malibu. However, the car/ the system as a whole is still not working propoerly so I spent an hour or two trying to fine-adjust the idle-mixture of the carburetor with the help of a 4-gas testing advice.
It's been difficult to get the car to a good running and a smooth idle condition despite most parts are new.
In 'P', the car now features a Lambda value of just below 1 (.996) which indicates an ideal air-to-fuel ratio (correct me if you think I'm mistkaen here); plus:
CO of 3.4% vol.,
CO2 of 10.0% vol.,
O2 of 3.2% vol,
HC of 1100 ppm
The HC figure is actually the one that strikes me most since this value is absolutely intolerable (for anyone with something like a sonscience, anf for everyone who has to pass emissions tests)! In my opinion, the limit acceptable is somewhere in the 400 ppm region.
The high HC indicates that a lot of gas goes unburnt through the exhaust whcih will certainly cause some damage to the car (well, and it's sad for the bucks going burnt in fact).
So what's wrong here, does anyone have a good idea?
The engine had been rebuilt some years ago, the distributor, plug wires and spark plus have been renewed too.

Thanks for your hints
Steven

 

[pontiacgp]

I would contact SIM and ask them what they think about the readings. SIM has some good reviews about helping out after the sale.

 

[pencero]

I object to your overzealous environmentalism. The oil companies don't have any qualms about destroying your environment, storing pet-coke outside on the South Side of Chicago, and flooding the air / water with chemicals and then bribing public officials in order to pass air quality / epa tests. If your car gets less than 20mpg what's the difference how many 'hydrocarbons' it puts out? That's a preposterous position to take. I am from Hammond Indiana where the Amoco plant is now BP oil, and they are refining lower quality tar sands using junk science lies to perpetuate the myth that these are somehow better and safer fuels for the environment when the reality is I live here: I can clearly see that these fuels are not what they were advertised to be and impact the environment negatively in my immediate area far worse than anything BP used to put out at the same location. Heart attacks are up. Lung cancer is up. The gas price is down - but so is the quality. You could never compete with the lack of respect for 'emissions tests' that oil companies like BP and Shell are putting into the environment at 100s of times the speed as you could ever hope to, so get over your conscience and relax. When the government successfully brainwashes people into accepting blame for the environment when truth told it is the fault of their lack of enforcement on industry and false promises entirely to blame, it's like they are creating a slave.

The oil companies are criminals with politicians on the take. They are KILLING PEOPLE IN CHICAGO AND INDIANA with no conscience. So why are you letting the same people killing us make you feel guilty at your house, inside your own garage? You are ultimately not responsible for any deaths / sudden heart attacks. You are not the criminals the oil industry is, and you might find the gas you are using is partially responsible for the increase in HC. The low quality of tar sands fuel and fracking are the type of issues environmentalists should be tackling. We need changes in future POLICY to make a real difference. Thinking you are making a difference in the garage to air quality is like quitting cigarettes to positively effect air quality in your neighborhood. It's a drop in the bucket. When my timing was off on my cutlass, there was scoring all over the carb from ethanol battle scars. When my Durango fuel pump went down, there were little pieces of sand in the fuel filter. This upcoming election is a big deal for what type of future policies we will see in terms of oil futures. The 2016 election outcome is crucial for the type of policy changes we really need to make a difference. If the wrong candidate wins, we will have more of the same: people guilting us in our garage while toxic chemicals continue to rain down on our roof tops unchecked, rigged EPA tests and media lies. Global warming is perpetuated by global industry executives, not your local hot rodders bad smog. Tar sands were a lie and a fassad! If we visit the neighborhoods where oil is refined, we find newer cars that put out less emissions parked everywhere - covered in dust from nearby production methods. We can take a baby wipe across a newer Ford parked on the South Side of Chicago, or Northwest Indiana and it will turn black with dust in seconds - right now. Something about the current environmental policy has Failed, but it was NOT you to blame, I can promise you that.

 

[pontiacgp]

Steve, why do you think it's a rich condition causing the high HC....it could be a lean condition that is causing that and there are more scenarios that cause cause the high readings..

http://cleanaircarcheck.com/pdfs/TestProceduresPartOne.pdf

 

[truracer20]

Your HC level could be due to crank case gases caused by blow by. Blow by for the most part will not be seen as smoke from the tailpipe. The stock lean burn condition these engines were tuned to was perfect for burning oil without smoke, to an extent. Also the rest of the emissions system has to be in good shape. The converters on these cars lose efficiency over time and much faster than engines with modern fuel injection. You also have to be sure that your vacuum advance is working to spec.Not all replacement distributors get that part correct and it is vital to emissions performance. Valve timing and camshaft specs will also have an effect on emissions. Check your air fuel ratio under driving conditions, if it's good then move on to the emissions system. If that checks out good move onto the engine itself.
And to be honest anybody with an environmental conscience wouldn't drive a car with that ancient emissions technology. They would swap in a complete modern power plant with an overdrive trans there by doubling power output, halving emissions output and nearly doubling fuel mileage...

 

[CWPottenger]

With high HC's check your timing, vacuum leaks, bad /leaking smog pump. Also could be a bad Cat, but that usually effects everything and car drive like poo...

To the Political/Enviro babble that is not helping him solve issue.

 

[Clone TIE Pilot]

Vacuum leaks cause lean misfires and high HC readings.

 

[gbody79malibu]

thanks, folks! To claify some points: The car doesn't have a catalyst anymore (had to be demounted) which of course does have some effect on the overall emissions.
So I will
- check vacuum hoses/ vauum leaks (done so in fact already - vacuum is about 17-18 in hg in 'P' which I assume would be fine)
- check proper timing
- check A/F ration under driving conditions (difficult though, as I cannot take the gas tester with me...)
- operation of the smog pump ( you mean the EGR?)
- Valve timing and camshaft specs will become more difficult for me to test ...

Maybe I should *ss that the engine is running extremely poor when it's cold and feels prone to turn off (in fact it alread happened). May this hint to the operation of the choke system (electrical choke by now)?
Well, yes, regarding the environmental consience you're right for sure, I shouldn't be driving that old stuff anyway and yes, there are companies harming our environment even more. But I sense that cleaner combustion would yimply a smoother engine operation too adn hram the engine less....

 

[CWPottenger]

If your choke is stuck or improperly set that will have a very negative effect on your engine's ability to run and burn fuel properly. I will let a QJet guru chime in on adjustment and what to look for since I'm not a Qjet fan.
For your emissions if you do not have a Cat or other components of the smog system you will have to change the mentality of how you tune the vehicle. All of the components of the emissions system on the car work together to capture, re-burn and chemically tie up or change the vapors in the exhaust. Without those components you have to set the timing curve, cam, ignition all up so you get the maximum amount of fuel burned in every cylinder. Usually for our generation of factory stock engine you can tune for emission or for power not both.

 

[truracer20]

Smog pump refers to the A.I.R(Air Injection Reactor) pump. Do you have small steel tubes going into your exhaust manifolds that also go to a belt driven pump on the front of the engine? If so that is the A.I.R system. Not all cars had them.
The catalytic converter has a large impact on tail pipe emissions.
As far as the poor idle I would start with checking the EGR valve for proper operation. If it leaks just a little at idle you will have a rough running engine. If it fails completely the engine will Either run extremely bad, not run or you will have pinging.
Does your engine have heat riser valves in the exhaust manifolds? Many times they stick and cause driveability issues.
A leak down test can help locate internal engine wear.
Yes you must check ignition timing, Spark plugs, wire, cap and rotor must be checked as well to be sure they are in good condition.
As far as the choke it should start out closed on a cold start then slowly it should open fully. They can be adjusted to open faster or slower but usually the factory setting works fine.
Besides the catalytic converter what other emissions equipment has been removed?