I put one of these engines in my 1986 Tercel 4WD wagon as the 3AC just didn’t have enough power. The 4WD wagon weighed about 400 pounds more than the 2 door hatch which has the same 3AC.
Anyway, issues with the distributor. Timing is 5 BTDC, not 10, both hoses disconnected and capped or plugged. Over time, the mechanical advance sticks and the weights need to be lubricated. Just spray a little oil on them and check them for movement by turning the rotor by hand and the wieghts should move. easy peasy.
Check again by running the engine with the vacuum lines off the distributor and rev the engine, the timing should advance to around 26 degrees at somewhere between 2400 -3200 RPM.
Next, test the vacuum advance. You can hook up a hose to each port and drawing a vacuum on each to see that they don’t leak, or just connect the vacuum lines back and check the timing at idle which should be around 13 BTDC.
If the weights were stuck or the vacuum advance was leaking, repairing them should make the engine run much better, however, neither of these went bad as a result of the smog test. They were bad long before.
The center shaft hole in the distributor body wearing out is also common after 200k miles or so. There are no bushings, you have to get a new distributor or find a machinist that can either knurl the shaft hole and rebore it or bore out the shaft and put in sleeves or bushings.
Thanks Keith for those great detailed triage steps.
All very worthwhile checks, especially on an old distributor. I’ve replaced distributors due to worn center shaft holes, but never thought about finding a machinist to knurl out the shaft.
Also, given the drop in power immediately after getting it back from the emission’s test, there’s one more thing I’d be curious about double-checking. And that is to verify the two vacuum hoses going to the vacuum advance were not mistakenly put back on to the wrong ports.
I believe one hose is ported vacuum and the other is manifold vacuum, with the ported hose going to the outer vacuum advance nipple, and the manifold hose going to the inner nipple.
I suggest that the OP should send a message to @george_san_jose, as George likely has some practical experience with an '80s era Toyota (this Chevy Nova is actually a Toyota Corolla) and could possibly provide some helpful hints.
George has absented himself from this forum for a few months, hence the suggestion of sending a direct message to him.
That could have happened. First thing I try is to disconnect the lines and then see if each line tends to want to go to a different port. When they have been in one position for a long time, they kind take a set. This may not work for this case as the ports are so close together, but it’s worth a try.
Edit: everything you ever wanted to know about your distributor and more.
Are emissions tests in California done in a state testing facility or are they done by any auto shop?
If done by an auto shop the mechanic may have fiddled with something to get it to pass.
When I lived in NY they were tested at shop.
Now I live in IL they test at a state facility. The state facility never opens the hood. If it doesn’t pass the license plates are not renewed and you have x days to get it fixed.
In NJ, the tests are run at a state facility that is operated by a private entity. They never open the hood.
With older cars, if they fail the emissions test, and if the owner can prove that it would cost more than x dollars (I don’t recall the amount) to repair the problem, then the owner can apply for a passing sticker.
We don’t have testing in Minnesota but the only thing that I wondered is if they pulled the battery cable to clear any codes. That would have reset the computer back to original settings. Then it would take drive cycles and time for it to relearn the settings. No udea why they would require testing a car this old.
The fastest and best way to test is read data from the OBD2 port. In MD you can go through the main building and have a technician run the test. There is also a kiosk on the side of the building where the driver can plug in himself and run the test. After it’s done, you get a printout with the results. I’ve used the kiosk for several years. The line is typically shorter and the test is easy to run.
Mechanic #1 said it seems that the distributor vacuum advance ports are leaky, but did not identify a timing problem. So the problem continued.
Mechanic #2 found that the timing (which I think means specifically ignition timing) was 10 degrees retarded. So this was corrected, and the operation since then has been mostly back to normal, certainly not messed up like it was after the smog test. The gas mileage seems to be back to normal as well. No idea why the timing would have been set so poorly at the emissions testing site.
Sounds like the smog tester simply retarded the timing to get it to pass the test. That should not be done. They should have simply failed the test. Why? It’s better for you really. There may have been something more seriously wrong with your car. Retarding the timing may have just masked the real issue.
Now that a mechanic has looked it over it should be fine.
That was always my understanding. And I too was surprised to see a test facility do adjustments (esp since you’re in Ca and I’m not).
But after following this thread, I see Calif also added test-and-repair smog facilities. Maybe that’s the kind of place where PaddyOFurniture went.
According to the www.bar.ca.gov/star site: The STAR program was created pursuant to Assembly Bill 2289 (Eng, Chapter 258, Statutes of 2010) to improve the overall quality of Smog Check inspections and help the state meet required emissions reductions. The program offers voluntary certification of Smog Check test-and-repair and test-only stations that must adhere to high inspection-based standards.
A search for “What are California STAR test-and-repair stations?” can show more.
I think the tester goofed. You said mechanic #2 found the timing 10 degrees retarded. That’s not normal. So the tester must have changed it and either did it wrong or kept dialing it back until the emissions cleared. Maybe that’s what he meant by spec. As in to meet the emission spec.
No, the emissions from this vehicle have always been low. Failed tests have only been due to items that make no real-world difference in terms of emissions or gas mileage – like the distributor vacuum advance, or the pre-heater hose. (That is, when the functional tests have failed, the actual measured emissions have been very low anyway.)
The spec for ignition timing is 5 degrees before top-dead center. It was probably at that when I arrived for the test, and the car was running fine. When I left, according to mechanic #2, the timing was 10 degrees retarded, which would be 5 degrees after top-dead center. The car was running poorly, fuel efficiency was reduced, I could not start the car a week later, and sometime after that I actually ran out of gas while driving. All corrected by mechanic #2 changing the timing to its normal setting.
At the test site, if the timing had been incorrect upon arrival – for example, 8 degrees before top-dead center – then the technician could have tweaked the timing to the specified timing, 5 BTDC. Then continue with other measurements – idle speed, measured emissions, etc.
I tried to discuss with mechanic #2 how such an error could have been made at the smog test site. He did not know what happened and did not come up with any scenario to explain it. One possible scenario that I can imagine: confusion between BEFORE and AFTER top-dead center (as in 5 BTDC and 5 ATDC). Ridiculous, but those are the figures that mechanic #2 identified as being relevant for the car’s problems with ignition timing.
