just got this 88 iroc with a 350 tpi . before i went for the emissions i changed the oil , o2 sensor , and gave it a tune up . they ran it twice so here are both reports . the car does not spit any engine codes , other than that i dont know much about the car because i have only had it about a week , as far as i know the car is stock .
any input on getting this to pass is appreciated .

 

Could be a bad cat or somthing got disconnected on your emissions. Check all lines to the smog pump and such to make sure its all hooked up.

 

Was the car plenty hot at the time of the test? It seems to have gotten better with the second test. HC is caused by unburnt fuel or incomplete combustion. That is usually caused by a skip, misfire, or rich condition.

Your numbers are very close. Do you run a 190 degree thermostat? a 160can keep things just cool enuff to cause trouble.

If you do run a 190 and teh car was properly warmed up , i would look at the cat. It might be reaching the end of its service life.

 

it is a 190 degree . i was just giving everything a once over and noticed a mouse chewed through vacume line . could this cause me to fail ?

 

Which vacume line was it?

 

it was under the plenum , it goes to a T . looks like it goes to the evaporator canister , throttle body and some were back by the distributor .

 

That is a possibility but im not an emissions expert. I just know where everything is since i tore it all out of my car (no inspection in KS). Im sure someone here will have more info.

 

The fact that it is idling at 1037 RPM is an indication something is not right. It should be idling around 600 RPM when warm. Put a vacuum gauge on the car it should be in the 18-24 inches of Mercury range or 30 Kpa if you can find a metric one. If the vacuume is right check to make sure the timing is at 6 degrees. People like to jack the timing up on these cars for better performance.

 

i was in the exact situation about 3 weeks ago and my car (88 tpi) failed emissions, it actually only failed in Hydro Carbons (HC) on IDLE. DId a complete tune up; set timing to stock settings (4 degrees advanced), wires, cap and rotor, o2 sensor, sparks plugs (put the delco's back on), etc etc. And......... the car still scored the same, it failed. Then i replaced the high flow cat with just a universal 3inch cat and my HC were cut in half. And it pass in all categories extremely well.

However, I don't really know why your idle is soo high. Check your lines and fix them and check / adjust your timing back to stock setting about 4 - 6 degrees.

Hope this helps.

Pat

 

checked the timing and it was at about 7 degrees .
ran it through the emissions again and it failed .

im gonna try putting a new cat on it and see what happens ...

 

the vacuum line chewed through caused a vacuum leak and raised ur idle. Whether this helped make you fail is a possibility. Try this next time I guarentee that you pass. I do it everytime I go for a sticker just in case. Get your fuel tank down to about an 1/8 to a 1/4 and put 3 bottles of dry gas. Right before the test take it for a blast down the highway to get it to operating temp. Go for the sticker I guarentee your numbers will be pretty low. Last time I did it was with my full size blazer and the numbers that came out of the machine was like a honda was on it it was so clean. give that a try.

 

These are all very good answers. I agree that you need to make sure the car is at operating temp. They cat needs to be hot in order to operate. Make sure you take a trip down the highway in passing gear for a little while. You don't have to drive like a maniac but get the rpms up a little. When you get to the station if they tell you to shut your car off don't. Also if you retard the timing a few degrees maybe 4 this should lower your hydrocarbons.
If you put your cat on it then most likely you will pass. I recently had an 85 eldorado that failed and this car runs really good but it wouldn't go through emissions. There was nothing at all wrong with the car but it was double the limit on everything. The cat looked brand new but when I changed it. It fast passed. Good Luck

 

well this proves to me that emissions testing is bull**** . tossed a $65 crappy universal cat on it and it passed . here is the report .

 

Glad you passed, but the broken vacuum line you described sounds like the one running to the EGR solenoid. That might cause some emissions trouble for you?

 

ya , that is were it went . fixed that , set the timing to 5 degrees and ajusted the tps before the 3rd try and it still failed . thats why i broke down and did the cat .

 

Oh ok, I didn't realize you'd already fixed the vacuum leak. Good call.

 

i have to ask, did the old cat have any guts in it?

 

ya . looked like oem .

 

I thought cars that were 95 and older didnt need to take emissions test any more?

 

I have no background in law, but that sounds like something that would be left up to each individual state.

 

my car is an 85 and i need to do emissions

 

I think it is only certain states. My mechanice said that a law just passed in Illinois saying that cars 95 and older dont have to take it. He said that they will be getting ride of all the dynos.

 

co= mixture problems- check ur injectors and/ or fuel pressure make sure its not leaking causing it to be rich

hc= misfire problems- check plugs (wires too) check gaskets, timing

as far as the high idle it sounds like u have a vacuum leak somewhere. spray water (like squirt bottle) over the intake manifold over all the vaccum hoses and check for leaks.

hate to say yea u bought the new cat to pass this year but next year u might fail again

 

actually have an update on this old thread .
the high idle / occasional wondering idle / and being a little hard to start when the motor was warm was getting to me so i started tinkering .
one day after driving (and the car was running a little crappy) i looked under the hood and thought i heard a hissing sound with the motor off .
i opened the throttle and it got louder . first thing that popped into my head was a leaking injector . i found an OEM set cheap so i figured what the hell .
put the new set in and it fixed all of the above problems .
im sure that was why i failed emissions because the car runs perfect now . i know it will pass next year and the person that said that the new cat might be a temporary fix was probably right ...

just figure i would update for others that may have a similar issue ...

 

I know how most people take advice but here goes anyway. Living in California for 57 years and dealing with their strict smog laws I learned a simple thing some time ago. I never go to a "test only" facility. I go where my car can be pre-tested before being hooked up to the computer. The short time I lived in Nevada years ago I had to take the car to a mechanic to have it pre-checked and then took it to a smog facility to have it smogged because the state would not allow smog shops to do repairs. What ever your situation, there is a way around it. If you are hooked up to the computer in California and fail, you are labeld a "gross polluter" and that follows you almost forever making bi-annual smog checks a major pain in the ***. To make a long story short, know it will pass before you take it in for the smog check