Questions and Answers

Tercel Has No Gumption

Q. 1990 Toyota Tercel 1.5 liter, carbureted, A/C, rack & pinion, no ABS, 117,000 miles. Problem: After the car is warmed up, when it shifts into second gear, it smothers out and if you continue holding the gas down, it will quit. Also, after it warms up, in park or neutral, you can rev the engine from 3000 to 3500 rpms, it starts missing and will go no higher in rpms. Already checked fuel pump, pressure is fine. Replaced distributor, rotor button, distributor cap, wires and plugs - no difference. Could it possibly be the ignitor?

Thanks for any insight you may be able to give me.
Kevin

A. Well, you have the basics covered pretty well. There are several things that could cause the symptoms you describe. One of which is the distributor Centrifugal Advance.

Inside the distributor there are two governor weights and two governor weight springs. These weights and springs are attached to the distributor shaft. A rotor shaft is also attached to the distributor shaft. As the distributor rotates, centrifugal force pulls the governor weights against the tension of the springs. As the weights spread apart, locating pins on the weights rotate the rotor shaft causing the ignition timing to be advanced. The amount of centrifugal advance is determined directly by the engine RPM (distributor rotating speed).

There is also a Vacuum Advance system that could be bad. The vacuum advance controls affect the time at which each spark plug fires. The ignition timing control system changes the ignition timing in response to manifold vacuum and engine coolant temperature. Utilizing a series of BVSV (bimetal vacuum switching valves), and check valves the spark control system regulates vacuum source from port to manifold vacuum. The distributor has 2 vacuum advance diaphragms, one diaphragm which connects to a ported manifold vacuum source to advance ignition timing after engine warm-up for maximum performance. The other diaphragm advances ignition timing during cold engine running.

If I read your letter correctly and you put a new distributor in, you can eliminate these possibilities. If you didn't put a new one in, or put in a used one, then they are possibilities.

The ignition coil and or ignitor could also be bad. I usually replace these as a set. The pick up coil inside the distributor can also be bad, sending the wrong signals.

Since these can all cause the same symptoms, I think your best bet would be to have the engine placed on an engine scope and checked. This will save you money by not throwing a lot of parts into the car until it's fixed.

Information provided courtesy of ALLDATA