2 normal spark plugs and 2 carbon fouled

[Petros]

too lean can lead to a high HC reading, check for vacuum leaks as well. Use carb cleaner spray to find it if have one (spary on hall hoses, gaskets, etc when it is running, when the spray gets sucked in it will change the speed of the engine).

[john]

Hello Petros and 4wdchico,

Tomorrow I will try looking for a vacuum leak. Will try the spray test. When I reinstalled the carb, all connections looked good. I checked the manifold bolts.

I did hook up my vacuum gauge the other day and it held steady at 15. Normal engine on my gauge should be between 17 and 22. Does 15 indicate a leak? timing is set to 5 degrees before.

As I mentioned, the car doesn't get to half on the temp gauge. closer to 1/4 to maybe 1/3 on the temp gauge and that is after coming off the freeway.

Here are the other smog check numbers. CO2 12.0 / O2 1.0 / this was at 14.1 mph with a load of 109.8 ftlbs

Any thoughts on why my NOX reading went up after cleaning my egr? I was really careful. I cleaned all passages.

maybe I better delay getting the cat.
thank you for your help.
john

[john]

Well, pretty good news. Yesterday I checked the thermostat and it was stuck open. A part of it was actually broken and it could not close. I replaced it and car will now heat to almost 1/2 when reved up real good. Had new cat put on. Took it to my usual smog shop for pre-test. Emission levels very low, however, the tech could not keep it on the dyno at high speed, the front end needs some work. The owner will not be in until tomorrow, but will bring some straps to tie down the front end. anyway, will go for the real test on Saturday or Monday. The tech felt like it will pass no problem. Thank you again for the great help. john

[john]

My tercel passed the smog check!!! Almost no detectable emissions!

Thank you to everybody!

Sincerely, John

[dlb]

good work, congrats!

[ARCHINSTL]

Bravo! How often do you have to face that in CA? Does it ever cease for mid-'80s cars?
Tom M.

[john]

I get to do this every two years, here in Fresno. The San Joaquin Valley traps smoggy air, so smog rules are quite strict. The air seems less smoggy to me than when I moved here in '79, so I guess it is worth it. Cars from 1974 and older are exempt from smog checks. Wish I still had my '73 Spitfire! Anyway, I do enjoy my Tercel and will keep it on the road!
john

[Ace]

I saw this post linked from another recent discussion (about trying to pass smog testing) and thought I would bump it up because it has a lot of potentially useful info. My Tercel is now 30 years old and I suspect I have some of these issues myself.

[stanrob]

If I may be permitted, I'll introduce my apparently closely related problem. My good old 85 has had an elusive gas smell, and its efficiency has gone down almost to 20mpg. Its #1 plug fouled a year ago, and despite replacement, again this week.

From my reading of this thread, I saw that the AAP membrane might be implicated. Well, I've just checked that out with my vacuum tester: there's no air or fuel leak, and it works. Next I began testing the TVSV. So far I've only tested it an ambient temperature (the middle of three tests needed per FSM EC-20). All five tubes are open to each other AND it won't sustain vacuum even with all five blocked! If they remain open when the engine is warmed up, that might explain the low MPG (AAP actuating every time I move the accelerator). It still doesn't explain the gas smell. I don't believe it's the tank because it becomes stronger when I'm driving. Tends to come and go. Would anybody like to venture an opinion on how to proceed?

[Petros]

running rich perhaps. check all systems that could result in running rich.

both the fuel pump and the diaphragm housing on the side of the carb can drip fuel onto the manifold that can give periodic gas smell.

[marlinh]

Plugged EGR valve.

[stanrob]

I apologize, I failed to mention that I've already replaced the fuel pump (using the one in my dead 83 Hatchback, which never had a gas smell). It made no difference. I will pursue EGR valve issue!

As regards the "diaphragm housing" mentioned by Petros, I'm guessing that you're talking about the AAP diaphragm's housing. I'll look again more carefully, but the fact that when I tested it the diaphragm held vacuum, and AAP squirted inside when vacuum was released, makes me suspect that we've eliminated that issue already.

I haven't heard any comment about my seemingly defective thermostatic switching valve. Am I right to suspect it may be the culprit for 20mpg?

[Petros]

the secondary throttle plate is vacuum actuated by a large vac diaphragm on the side of the carb where the throttle cable attaches. If it gets leaky it will drip fuel on the heat sheild that quickly evaporates. Mine as done that for years, very annoying.