TA22 No Spark/starting problem

[Lambolica]

Gents,

I jumped in the Celica to go to work this morning and She wouldn't keep running.

If I kept the Key on Start the engine would fire and run, rev etc, but as soon as I release the Key the engine would immediatly die.

This is a Stock TA22 with a 2TC, and it was running fine yesterday.

I was on short notice this morning anything too extensively, but looking quickly at a wiring diagram, seems to indicate that power goes from the battery --> Key --> fuse box --> Coil with very little in between.

15A fuse is OK in the Fuse box.
There is power to the indicators etc that run off the same wiring from the "ON" key.
If I ran power from the Battery to the +ve on the coil. the car would run, but very poorly, then stopped idling.

I didn't check to see if there was power at the +ve on the Coil.

What I'm looking for here is what the problem might be. I'm thinking that the Coil may be an issue, but other things to check would be helpful.

Cheers
Simon

[ta22fan]

I'd start with checking your points - I've seen problems a bit like this caused by a bit of oil/dirt partially shorting the points gap. Also, give it a try this arvo - could be old high tension leads which can absorb moisture overnight causing higher than normal resistance - when this happens they often come good after a few hours in the warm/dry. Sounds like you've got 12V from the "Start" circuit to the coil (lead runs from the solenoid direct to coil +ve terminal) - check the normal running 12V circuit that runs to the ballast resistor on top of the coil, and then to the +ve coil terminal. You should have roughly 9V across the coil terminals from this circuit with the ignition in the ON position (points closed). If all that checks out, I'd swap the coil out as a next step.

[pandaah]

Also making sure the idle circuit shut of solenoid is powered up as that will cause stalling, easy easy to test is keep the car on revs see if it stats alive, that's what it sounds like to me how you say it idles rough then stalls

[allencr]

Classic symptom for a Ballast resistor.
Also, file/reset the points after their stint at taking the full current.

[Dazza]

Yep it sounds like the ballast resistor to me. If the ballast resistor is ok then it must be the ignition switch.

[Dan_k36]

Ballast playing up

[Lambolica]

For those who vote for ballast resistors you prize is in the mail.

As soon as I found my circuit tester, I found no voltage at the coil side of the resistor.

But thanks to those who chipped in with some answers, I was able to get the missus to get a coil and ballast to swap in to night whilst I was at work.

It had me buggered as to why there was spark under start but none at "on" but closer inspection at wiring diagrams has answered that as well.

Now to look closer at that electronic ignition conversion I found when searching.

Cheers
Simon

[roadkill]

Hi,

in case you don't know the coil is provided a higher voltage under cranking (basically bypasses the ballast resistor) to make sure it starts easier, once it is no longer cranking the ballast resister comes into effect and drops the voltage to help lengthen the life of the coil.

bEn

[Lambolica]

Yes,

Wiring diagram indicates power to the coil straight from the Starter motor for cranking.

Cheers
Simon

[Dazza]

You can normally get away with bypassing the ballast resistor for a short time to get yourself out of trouble if you are stranded, but the coil will get hot and start breaking down on a long trip.

[ctrain]

i was also going to say ballast resistor, can i have a prize too?

Id also like to add, if you get a new coil, say a bosch su12 (common replacement) you will need to remove the resistor out of the loom, an su12r requires a resitor though