96' Camry... coil 'spark' with engine off - Toyota Nation Forum : Toyota Car and Truck Forums

cintronfamily · 08-15-2011, 09:34 PM

I have a 96 4cyl. Camry and have trouble with it today. It was running fine and then the engine stalled. I try to start it and after 10 mins. it started but it ran for just a few more miles and died again. I check everything like suggested here:

DIY : HELP 92-96 5sfe CAMRY WONT START

The only thing I found odd is that when I turned the key (before starting the engine) I heard an intermitent clicking noise coming from the distributor. Also the tachometer needle was jumping intermittently... I checked and there was a spark coming from the coil (all this with the engine off). I measure resistance for the pick up coil, the Crankshaft sensor and the coil (primary and secondary) and everything is in between specs. I suspect the Igniter is sending voltage to the coil without reason... but why? Is there a way to test the Igniter? Could it be the ECM...?

PS I started the engine and ran the car for 1/2 an hr. without problems... but I'm still concerned it will happen again.

dc_98_cam · 08-16-2011, 01:36 AM

... I don't have a gen 3 ... I used to work on a lot of distributor engines.
Intermittent problems often require a trial and error process ... replacing one thing at a time.

That being said:

Are the metal electrodes inside the distributor cap reasonably clean?
If the metal electrodes are covered with a layer of oxide ... they will not efficiently conduct the high voltage spark current to the spark plugs. It could be that this is the cause of your intermittent problem.
If there is any question at all about the integrity or functionality of your distributor cap, consider getting a new one.

I can't be certain, but I have seen faulty distributor caps cause problems similar to what you have described. Typically, the car will stop running at a stoplight or stop sign. It will start again when the engine has cooled down a little.

cintronfamily · 08-16-2011, 06:35 AM

Thanks for your reply... I change the distributor already thinking this was the problem but still the same. The thing is that the coil is 'firing' with the engine off... and I'm sure is firing erratically when trying to start the engine. That's why I suspect the Igniter could be causing this (if not the ECM...)

PS I drove the car this morning to work without a problem... but I'm still nervous it will do it again

Stillrunning · 08-16-2011, 08:08 AM

The igniter is a switch controlled by the ECU to turn the primary voltage (12v) of the coil on/off to produce secondary voltage. The ECU switches the primary voltage negative to ground on/off which causes 12v flow to ground or not. When the ignition switch is turned to run 12v+ is sent to primary of the coil and the igniter, as the engine is started that 12v+ is grounded on/off (switched) to produce secondary voltage. The igniter also sends signal to tachometer. It is possible you have a short in the igniter which is grounding the 12v from the ignition switch causing constant flow through the primary. I would inspect/replace the igniter before blaming the ECU.

cintronfamily · 08-16-2011, 11:16 AM

I agree... is there a way of testing the Igniter? (resistance/continuity)

dc_98_cam · 08-16-2011, 11:32 AM

There was a recent post ... the problem turned out to be a wire going between the ignitor unit and the ECM ... behind the glovebox. The wire had somehow lost its insulation and was touching metal of some sort.

You might try inspecting these wires for any bare spots ... frayed insulation ... especially at any point the wire might be chafing against something.

Stillrunning · 08-16-2011, 12:34 PM

Quote:

Originally Posted by cintronfamily

... is there a way of testing the Igniter? (resistance/continuity)

All I've read is test all the other components and if they all test OK it must be the igniter. Even my FSM does not provide a test method.

dc_98_cam · 08-16-2011, 04:17 PM

Quote:

Originally Posted by cintronfamily

... 'firing' with the engine off... and I'm sure is firing erratically when trying to start the engine...

If there is erratic firing one thing that could cause it is the trigger wire coming from the ECM. ...
If there is still a problem, try to take a look at ... carefully inspect ... the wires that go to the ignitor.

The wiring diagram for the ignitor shows:
the white wire is the trigger from the ECM
the white wire with a red stripe ... the one that goes to the ECM, is the
..... confirmation of spark signal ...
a second white wire with a red stripe goes to the battery
a black wire with a red stripe goes to negative terminal of coil
a black wire goes to tachometer

So, it looks like your choices are getting fewer, more expensive.
Try a salvage yard ... ignitor, ECM.

Give us an update when you have time ....

cintronfamily · 08-16-2011, 07:00 PM

So... today my car would not start... I checked the wires coming from and to the Igniter from the ECM. They look perfect no indication of wearing whatsoever. Same 'spark' noise at the coil/Igniter area and tachometer jumping with just the key in the 'ON' position (engine off). Sometimes the engine will 'turn' for a moment with just turning the key from OFF to ON because of the 'spark'.

Half an hour later the car started and ran fine! I moved all the wires inspected above trying to find a faulted wire... nothing. I'll try to find an Igniter and see what happens...

PS The only component telling the ECU to send the signal to the Igniter is the Crankshaft positioning sensor, right? (although I measure resistance and was in spec.)

dc_98_cam · 08-16-2011, 08:35 PM

I looked at the wiring diagrams, and it seems that the signals that cause the ECM to generate the spark signal to the Ignitor come from the distributor.

I could not find a crank position sensor on the Gen 3. The Gen 4 has one, but not the Gen 3 ... at least the 5s-fe version.

... Just curious ... How are the spark plug wires on you car?
Do you know if they have ever been replaced? Do you think they are ok?

cintronfamily · 08-17-2011, 11:57 AM

Quote:

Originally Posted by dc_98_cam

I looked at the wiring diagrams, and it seems that the signals that cause the ECM to generate the spark signal to the Ignitor come from the distributor.

I could not find a crank position sensor on the Gen 3. The Gen 4 has one, but not the Gen 3 ... at least the 5s-fe version.

... Just curious ... How are the spark plug wires on you car?
Do you know if they have ever been replaced? Do you think they are ok?

I checked the Hall Effect sensor @ the distributor and looks fine... (I even replace the distributor just in case) This sensor just sends a signal every revolution of the distributor.

There should be a crankshaft sensor in the front of the engine...

The spark plug wires were replaced not long time ago... besides I'm getting 'spark' before trying to start the car (key in the 'ON' possition)

dc_98_cam · 08-17-2011, 12:43 PM

If you do have a crank shaft sensor, and also a cam shaft position sensor, then your engine is built like a Gen 4 ... 1997 to 2001, than a Gen 3, which was built from 1992-1996.

Regretfully, I don't really understand what is going wrong.
You might exchange the ignitor with another one ... but no guarantees with that.
If the ECM is the problem ... then as you suggested... it could be a faulty input to the ECM, or maybe the ECM itself.

Stillrunning · 08-17-2011, 01:10 PM

You might be able to use a 12v test light from coil primary (maybe at igniter) from 12v connection to ground then crank engine and test light should flash off/on. Connection may have to be in series rather than parallel depending on connection point.

cintronfamily · 08-17-2011, 07:59 PM

Quote:

Originally Posted by dc_98_cam

If you do have a crank shaft sensor, and also a cam shaft position sensor, then your engine is built like a Gen 4 ... 1997 to 2001, than a Gen 3, which was built from 1992-1996.

Regretfully, I don't really understand what is going wrong.
You might exchange the ignitor with another one ... but no guarantees with that.
If the ECM is the problem ... then as you suggested... it could be a faulty input to the ECM, or maybe the ECM itself.

So... a few things... I notice that in the book and in this forum it shows the distributor with 4 wires - Mine has only 2. Also there's a sensor by the crankshaft pulley, and I'm pretty sure is a Crankshaft sensor.

That being said... this engine has to be a Gen 4 engine!

(I'm not the original owner of the car... hmmmmm)

Does anyone has a diagram of the system and/or the specs. for the sensor?

hill8570 · 08-17-2011, 08:08 PM

Quote:

Originally Posted by cintronfamily

So... a few things... I notice that in the book and in this forum it shows the distributor with 4 wires - Mine has only 2. Also there's a sensor by the crankshaft pulley, and I'm pretty sure is a Crankshaft sensor.

That being said... this engine has to be a Gen 4 engine!

(I'm not the original owner of the car... hmmmmm)

Does anyone has a diagram of the system and/or the specs. for the sensor?

1996 is when they went to OBD2 on the 5S-FE, and a lot of things changed...among other things they added the cam and crank sensors, and the distributor was no longer mechanical (there is no mechanical connection from the camshaft to the dizzy). I think the '96 still had a single coil, but I'm not 100% sure when they went from single-coil to waste spark (two coils).

Wish I could be of more help, but I don't have a 1996 FSM, so I'd be guessing pretty hard -- your '96 is quite a bit different in that area than my '95.