Spray distributor - car starts up again!

[Octavius]

This is a continuation of the "Conks out" thread but maybe a bit more interesting.

(History: Just replaced ignition coil with a $40 one from Advance Auto.)

Car conks out again in traffic. Does not want to start up again.
Happen to have a spray bottle of cleaner on the passenger seat.
Spray the distributor in an attempt to cool the ignition coil down and the car starts right up! Got home OK. Phew!

It's hotter than Hades here in NC - when it cools down a bit I'll measure the resistances of this new coil. I measured them before I put it in.

Other than that, I'm hoping for any ideas. Any ideas! For example, what in the distributor is susceptible to heat?

[Octavius]

Just had a horrible thought.

I think there was a horse-shoe gasket between the distributor and the coil. It disintergrated on cleaning. I meant to make another one from cork or something but totally forgot.

I'm betting that gasket is to prevent heat transfer to the coil. The gasket was not 100% there anywhere - maybe that caused the original Toyota coil to overheat.

Whaddya think?

[Octavius]

This is where the original gasket was:

[Doctor J]

No that gasket should not be a problem (it is made of rubber)
have you put a new rotor?
I spend 2 days trying to start my camry due to the crack in the rotor which caused a weak spark.
check for the codes right now, unless you disconneted the battery again.
No codes=secondary ignition or fuel delivery system

[AlaricD]

Originally Posted by Octavius

...what in the distributor is susceptible to heat?

The Hall effect sensor.

[Doctor J]

Then the code 12 should be present

[AlaricD]

Originally Posted by Doctor J

Then the code 12 should be present

You'd think so.

I had an '86 Corolla that had a bad Hall effect sensor; when it got hot from driving, or from a heatsoak condition after parking somewhere (which was more frequent than just from driving), there were no codes. It'd develop an open short when hot, which would resolve itself when it was sprayed with brake cleaner.

The heatsoak condition made it a real mystery-- because the car would take me to work, but I couldn't drive anywhere for lunch-- and then it'd start up when it was time to go home.

[Octavius]

Doctor J and AlaricD,

No engine codes.

Here's the plan:

Order up the following from RockAuto:

Distributor cap with plug leads
Rotor
NGK plugs
Beck Arnley igntion coil
Anything else?

If that doesn't work then get a distributor from the junkyard (for the Hall effect gizmo)

If that doesn't work get a throttle body from the junkyard (for the idle speed gizmo)

Any thoughts?

Cheers

PS Then again, I may just buy a new distributor, complete with cap and wires. Sound good?

[Doctor J]

if no signal is coming from pick-up coils for at least 1/4 second, the code should be present.
obtain the spark tester and when the engine dies check for the spark.


also before ordering all the parts,
check for the power and ground at the ECU computer
Check the throttle position sensor adjustment; the 3-wire box shaped sensor usually goes bad on 2 gen camry get the same one from 90-s mazda protege (as I did on my friiend's car due to the stallling under acceleration.
And verify that there is no airleaks between AFM and throttle body

[AlaricD]

Originally Posted by Octavius

Beck Arnley igntion coil

You already got a new coil. The coil is a red herring. The coil is only acting based on the rest of the ignition system; if the Hall effect sensor isn't working, the coil will have nothing to do.

You need to check the Hall effect sensor. It's very easy to test with a multimeter; or a test light in situ. Do not replace it unless you know it's bad!

You can use any sparkplug, or even a screwdriver as a spark tester-- but it won't tell you why there's no spark.

Originally Posted by Doctor J

if no signal is coming from pick-up coils for at least 1/4 second, the code should be present.

Should, but my '86 Corolla never coded.

PS Then again, I may just buy a new distributor, complete with cap and wires. Sound good?

It doesn't sound good. Don't just throw parts at a problem-- find out what the problem is.

[Octavius]

Doctor J,

Thanks for the pointers - hopefuly I'll be able to check on those later today.

AlaricD,

Thanks for the advice. The resistances on the Hall gizmo (Signal Generator/Pickup Coil, right?) were both 226 ohms on my digital (confirmed on my analog meter) Spec is 140 to 180 ohms.
(Airgap is about 18 thou (spec is 8 to 16 thou), though Haynes says this is for the 1983 to 1986 - mine is a 1990))

Haynes says to replace distributor - should I go ahead? RockAuto has a bunch - any recommendations or ones to stay away from?

Cheers!

PS How do you use a test light to check out the Hall sensor?

[AlaricD]

Originally Posted by Octavius

The resistances on the Hall gizmo (Signal Generator/Pickup Coil, right?) were both 226 ohms on my digital (confirmed on my analog meter) Spec is 140 to 180 ohms.
PS How do you use a test light to check out the Hall sensor?

I'll bet when it gets hot it jumps to 'infinity', and then when chilled goes back down.

It's been ages since I've tested one, but basically the sensor switches on and off when the magnet passes by it on the distributor shaft. I believe you just hook up the light in series between its output and the coil input.

Of course, if you're doing these tests and you're not experiencing the 'no start' condition in the first place, it doesn't prove much. Again, though, heating the sensor should cause a no start condition.

[Octavius]

May have something here:

As the Doc suggested, I 've just measured the resistances of the Throttle Position Sensor:



The first two readings indicate it is kaput? I have not messed with the throttle stop screw - is it worth adjusting?

Cheers

[AlaricD]

Originally Posted by Octavius

May have something here:

As the Doc suggested, I 've just measured the resistances of the Throttle Position Sensor:



The first two readings indicate it is kaput? I have not messed with the throttle stop screw - is it worth adjusting?

Cheers

It does look like there are some issues there... not sure if it's also suffering from a heating issue.

I'm not sure if the car will run without the TPS connected (I've never messed with that, I do know that my '01 Corolla will run without the MAF connected, it just lights the CEL). If it will, that will help determine if the TPS is contributing to the problem.

I'd recommend against adjusting the screw without carefully indexing how far in what direction you turn it. (Even then, it's something I'd not disturb myself.)

[Doctor J]

My 87 camry did run with TPS disconnected.
88on can be different
The resistance of pick-up coils is good; the specks are different for 90-91 from 88 are given in Haynes
This type of TPS can be adjusted by slowly rotating it with the feeler gage inserted between the lever and throttle stop screw (loosen 2 screws for TPS); DO NOT adlust throttle stop screw.