87 Corolla didnt pass smog check...

cabbage · 04-26-2004, 08:15 PM

Hey guys, my girlfriends 87 fwd corolla didnt pass the smog check, it has a carburated engine, burns alot of oil (did a coolant diagnosis, head gasket not blown). During the test, the HC readings were way too high in idle (should be under 120 but its over 1500

at 2500rpm, the HC level went down to 150) I read somewhere that this means its running rich? Combustion incomplete

? Im going to check the valve clearances tomorrow, is there anything else I can do?

Thanks!

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EDGE · 04-26-2004, 08:25 PM

Change the oil then restate inspect it, worked for a friend and I've heard of others do it.

cabbage · 04-26-2004, 08:29 PM

Quote:

Originally Posted by EDGE

Change the oil then restate inspect it, worked for a friend and I've heard of others do it.

Thanks for the reply EDGE! well... truth is, I changed the oil the night before the smog check... maybe I shouldnt have changed it, there was only one quart left and wasnt smoking, after I changed it with the oil at the correct level, it started to burn oil again

**Yoda** · 04-26-2004, 08:30 PM

HC is unbuned fuel

Was the car FULLY warmed up? We used to tell our shop customers it was easier to pass at the test station that was 20 miles away, but it was really the freeway drive got them warmed up.
Float level OK in carb? (some have a site glass)
Choke coming off ok when warm?
Spark plugs?
New engine oil? (old oil can affect the readings if it has been running rich)
Any codes on the computer?
Cat Converter

Adding a couple bottles of "gas dry" sometimes helps (but yours are really hi)

HaveBlue · 04-26-2004, 08:36 PM

Quote:

Originally Posted by cabbage

Hey guys, my girlfriends 87 fwd corolla didnt pass the smog check, it has a carburated engine, burns alot of oil (did a coolant diagnosis, head gasket not blown). During the test, the HC readings were way too high in idle (should be under 120 but its over 1500

at 2500rpm, the HC level went down to 150) I read somewhere that this means its running rich? Combustion incomplete

? Im going to check the valve clearances tomorrow, is there anything else I can do?

Thanks!

What a coinkidink. I have the same car.
These cars are very touchy when it comes to timing. They must be set dead-on for everything to run right. Here's what I recommend:
Check the timing. The Vehicle Emission Control Label under the hood should tell you what the timing should be set at.
Replace the PVC valve. A stupid $3.00 part can make all the difference in the world.
Change the spark plugs and wires, cap and rotor. Go with a larger wire. The 4A-C reacts really well to a set of 8mm wires. Stick with copper plugs. Bosch Platinums suck on these engines. Replace the cap and rotor with quality parts.
Replace the air filter if you haven't already.
Check/Adjust the valves. The intake valves should be set at .008" and the exhaust at .012".
Replace the fuel filter. Another $3 part that can change everything.
Clean the carb. These carbs are relatively simple to take apart and maintain. Use tape to label all vacuum hoses. The 4 bolts to take the carb off the plenum are easy to get too with a shallow socket and extension. After that, there are 7 or 8 phillips screw to lift the top of the carb away from the lower part. You'll have to disconnect a couple linkages. Be careful of the little hairpin clips. They'll get away form you real quick. When you lift the top part away, watch for a little (approz 5mm) O-ring between the barrels. I almost lost mine then I forgot to re-install it. It won't run at all if you forget it. Pull the pin holding the float in place and be ready to catch the needle. Spray the float bowl, needle, seat, and everything else liberally with carb cleaner. Make sure no varnish is left on anything. Especially they secondary throttle plate.
Check/Replace the catalytic convertor.

That's all I can think of right now. I did all this last year to my car and it passed emissions with better results than when it was new.

Good luck! E-mail me if you have any questions or need any pointers.

cabbage · 04-26-2004, 08:39 PM

Quote:

Originally Posted by Yoda

HC is unbuned fuel

Was the car FULLY warmed up? We used to tell our shop customers it was easier to pass at the test station that was 20 miles away, but it was really the freeway drive got them warmed up.
Float level OK in carb? (some have a site glass)
Choke coming off ok when warm?
Spark plugs?
New engine oil? (old oil can affect the readings if it has been running rich)
Any codes on the computer?
Cat Converter

Adding a couple bottles of "gas dry" sometimes helps (but yours are really hi)

Thanks yoda, thats alot of info for me to start researching on! Yes the car was fully warmed, I even took it on the highway for the first time (her dad put in the new engine a few years ago and told her never to drive on the highway) and it actually went up to 80!

I will check the spark plugs tomorrow, I'm not familiar with carbs, gotta do some reading.

cabbage · 04-26-2004, 08:48 PM

Quote:

Originally Posted by HaveBlue

What a coinkidink. I have the same car.
These cars are very touchy when it comes to timing. They must be set dead-on for everything to run right. Here's what I recommend:
Check the timing. The Vehicle Emission Control Label under the hood should tell you what the timing should be set at.
Replace the PVC valve. A stupid $3.00 part can make all the difference in the world.
Change the spark plugs and wires, cap and rotor. Go with a larger wire. The 4A-C reacts really well to a set of 8mm wires. Stick with copper plugs. Bosch Platinums suck on these engines. Replace the cap and rotor with quality parts.
Replace the air filter if you haven't already.
Check/Adjust the valves. The intake valves should be set at .008" and the exhaust at .012".
Replace the fuel filter. Another $3 part that can change everything.
Clean the carb. These carbs are relatively simple to take apart and maintain. Use tape to label all vacuum hoses. The 4 bolts to take the carb off the plenum are easy to get too with a shallow socket and extension. After that, there are 7 or 8 phillips screw to lift the top of the carb away from the lower part. You'll have to disconnect a couple linkages. Be careful of the little hairpin clips. They'll get away form you real quick. When you lift the top part away, watch for a little (approz 5mm) O-ring between the barrels. I almost lost mine then I forgot to re-install it. It won't run at all if you forget it. Pull the pin holding the float in place and be ready to catch the needle. Spray the float bowl, needle, seat, and everything else liberally with carb cleaner. Make sure no varnish is left on anything. Especially they secondary throttle plate.
Check/Replace the catalytic convertor.

That's all I can think of right now. I did all this last year to my car and it passed emissions with better results than when it was new.

Good luck! E-mail me if you have any questions or need any pointers.

WoW... that was fast! Thanks HaveBlue! Yup the timing was pretty off, the mechanic (her best friends dad, also owner of the shop) spent at least an hour adjusting the idle, timing, warming it up.... Im thinking about taking the carb out, so thanks for the quick writeup.

The mechanic also suggested to change the catalytic convertor too if all else doesnt help.

Thanks again guys!

cabbage · 05-03-2004, 03:00 PM

Update: We passed!!! Did what you guys suggested (exept for the catalytic convertor), it wasnt an easy pass, it took us 2 hours to find what was keeping the idle so high, a few valcum hoses with no where to be plugged... after a few burnt fingertips it passed!

I think the main problem that caused the readings to be so off were the valcum hoses, my girlfriends father miss plugged a few hoses...

and the idle wasnt adjusted right, but we got it all figured out and I learned so much more

Thanks guys!

HaveBlue · 05-03-2004, 05:54 PM

Congratulations! How's it running?

04-26-2004, 08:25 PM	#2 (permalink)
EDGE Registered User Join Date: Jan 2003 Location: outside NYC Posts: 2,038	Change the oil then restate inspect it, worked for a friend and I've heard of others do it. __________________ 2003 ES300 2003 V8 LTD 4Runner 2006 Nissan Maxima SE

04-26-2004, 08:30 PM	#4 (permalink)
Yoda Super Moderator Staff Join Date: May 2002 Location: North Bend, WA Posts: 2,664	HC is unbuned fuel Was the car FULLY warmed up? We used to tell our shop customers it was easier to pass at the test station that was 20 miles away, but it was really the freeway drive got them warmed up. Float level OK in carb? (some have a site glass) Choke coming off ok when warm? Spark plugs? New engine oil? (old oil can affect the readings if it has been running rich) Any codes on the computer? Cat Converter Adding a couple bottles of "gas dry" sometimes helps (but yours are really hi) __________________ David TLCA 14788 71 Landcruiser FJ-40 TBI 327, TH-350, Warn 8000, disk axle swap. 76 Landcruiser FJ-40 project/parts (haven't decided)

05-03-2004, 03:00 PM	#8 (permalink)
cabbage Contributing Member Join Date: May 2003 Location: Santa Maria, CA Posts: 621	Update: We passed!!! Did what you guys suggested (exept for the catalytic convertor), it wasnt an easy pass, it took us 2 hours to find what was keeping the idle so high, a few valcum hoses with no where to be plugged... after a few burnt fingertips it passed! I think the main problem that caused the readings to be so off were the valcum hoses, my girlfriends father miss plugged a few hoses... and the idle wasnt adjusted right, but we got it all figured out and I learned so much more Thanks guys! __________________ Milton 01 Tacoma access cab 4x4 TRD TC Long travel, Supercharged 04 Tacoma Doublecab 4x4 TRD hoes all around! Last edited by cabbage; 05-03-2004 at 03:01 PM.

05-03-2004, 05:54 PM	#9 (permalink)
HaveBlue Contributing Member Join Date: Jul 2002 Location: Colorado Posts: 2,667	Congratulations! How's it running? __________________ Alan *1996 Supercharged 4Runner Limited* Hi Altitude 4Lo A 4WD club for Colorado and surrounding states

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