state of ohio vehicle inspection report it doesnt look good

[chevy68388]

as of today my truck is no longer on the road for some time i failed for the second time
emissions hc 2046.9 that was mine the limit u can have is 155.0
the co mine was 7.46 limit is1.91
and last was co2 mine is 8.49 limit ? but any way i failed what i need to know is how can i get this truck to pass this is not kool at all i cant even get a 30 day tag and no this isnt the 68 its the 87 i has to be inspected for emissions stuff that it dosent have any more o how do i hate e check

[Tom]

You took all the emissions stuff off on a emissions vehicle????

Time to put the cats back on

[pkbinplano]

ouch !

[chevy68388]

the only thing it has is cats the other owner took it all off and i put cats on it

[Piston]

Get a different station to do the inspection (if they have any)

I"ll have to double check my numbers but 155 on HC is not right.
Maybe 1550 or there abouts... Heck I've picked up 155ppm HC in a cooling system with a very slight headgasket problem.
Does it run ok?

[chevy68388]

runs fine thats what it says on my paper that the limit is 155.o mine read 2046.9 what is the hc like what doe it stand for

[Piston]

HydroCarbon.

Do they have many inspection stations? Or is there only the County run facility?

[chevy68388]

just county

[swervin ervin]

Dayum, that is some way high numbers. At my last test, in August, my HC was 67, standard is 220.

My engine is far from being stock, but I do have all my emissions equipment hooked up and working. It sounds to me you only have the cat on the truck, right? You need the A.I.R. pump and EGR also. I think this may be why you are running so high.

What has the previous owner took off. It's a TBI, so I'm guessing you have something not working correctly. Is the computer still working? It looks like you are going to have to drop back and punt on this deal.

[79BIG10]

I failed mine the first time as well. This is what I did to help it to pass. Cleaned air filter (K&N), new plugs, new oil and filter, reduced timing to about 6 BTDC, and retuned carb. Also make sure to have the engine nice and warm. This helps burn off any carbon residue. Also get some GM topside engine cleaner. This will help for sure in cleaning out the combustion chambers and rid of carbon.

[Hooter]

sounds like you are running waay too rich. My 74 cheyenne passed air care. And it was a 454 without any emissions! I guess they must have really low standards for a 454

[Piston]

Luckily, Kansas doesnt have emissions testing (YET).

[gchemist]

Can increasing the spark gap and high octane fuel help? CH3-OH might be helpful.

If emissions ever come to my area I'm going TPI!!

[mckpaul]

Well, sucks to hear that, but good to hear I'm not the only one out here putting back stuff someone else took off.

Swervin is right about the A.I.R. pump. Doing some research, I read where the air pump injects air into the exhaust, before the cat, reducing the raw hydro-carbons entering the cat. However it injects air AFTER the enging is warm (via the diverter valve and thermal vacuum switch). When the engine is cold and warming up, it doesn't inject air, so there's a higher concentration of hydro-carbons going to the cat which makes it warm up quick. With no air injection after warm up, the cat overheats and starts to plug. So no air injection combined with possible messed up cat could be part of the high hydro-carbon problem. (The diverter valve also has to do with controlling air flow during decelerating or operating at continuous high speeds preventing backfiring in the manifold)

This is assuming you originally HAD an air pump. Mine is an '84, for the '87, they may have had a different way of controlling the hydro-carbons. But if you see an air pump diverter valve on your vacuum diagram, you originally had an air pump.

I read something about the EGR having to do with controlling oxides of nitrogen, and that it can cause you to fail emissions tests if it's not working, but can't remember details. Just know I have to make mine work again.

Good luck!

[Tom]

g, I think increasing the spark plug gap and octane gas will raise the emissions. The larger spark plug gap might make it too hard for the spark to arck and not ignite the combustion process as well. Same thing for the higher octane gas: it will burn slower and problably not as complete resulting in more un-burned gas going into the exuast.

chevy68388- somthing isent right. I just went threw emissions with my 79. It only has the cats also. While my PPM were always low, the first time I had like 8. somthing CO. I turned down the timing, leaned out the idle mixture, and BAM! 0.0 CO and 150PPM. Thats like no emissions . Sure does stink when it comes out that way though
I think you just need to tune much better. Tune up, oil change, carb tuning, timing change.

[chevy68388]

man u guys are telling me i kow this sucks hardim going to lean it up tommarow moring and put this stuff in it said it will make it pass i may put a little alcohal in it we did this a few time to make my friends 79 pass e check when it had to o im not sure who said it but it isnt a tbi its carbed it was a 305 truck now it has a mild built 406

[swervin ervin]

What kind of carb have you got?

For those interested, I read a article somewhere a long time ago by one of the Chevy gurus about octane. He said, you make the most horsepower with lower octane fuel, because it burns faster and more complete, as Tom said. All the octane does is slow the burning process down and is why a engine with a lot of compression ratio, or timing requires it. So for more power and to save money, run the lowest octane gas you can. Besides, it's all in the timing anyway. I hear folks all the time say they run premium just because they think it's better for their engine. Wrong. It don't do a dang thing except waste their money if they don't need it.

[chevy68388]

the carb is a holley 4160 bty how do i lean this carb out like witch screaw is it and what way it gets it last try tommarowim going to run some stuff thats says it will make it pass and i have this nos stuff that all ways makes every thing ive ever ran it in hot and burn clean