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Igniter and Engine Control Module Test, 1996 Toyota Camry

My old 1996 Camry with 2200 cc 4 cylinder engine, frequently keeps losing power to the spark plugs. I have changed the fuel filter and the ignition coil. That did not help. I also noticed that the car was starting when I unplug and replug the primary wire plug to the ignition coil. So I have replaced the primary power plug with a six inch pigtail and a used plug purchased from a salvage yard. This is not helping either. The Toyota dealer near my house want to replace the igniter and the Engine Control Module just to be sure that these are not the sources of problem. Well, the estimated cost of the suggested repair is $1500/- on a car that is worth about $2000/-. The dealer did not test these parts. So I refused to replace the parts without a proper test. I would like to test these parts. Is there a test available for the igniter and ECM that could be performed. I have access to a lot of tools. I need a schematic and/or test to test these components. Please help.

Try swapping out the ignitor with a used one if you can. They are a fairly common point of failure. I doubt the ECU has a problem.

"Toyota dealer near my house want to replace the igniter and the Engine Control Module just to be sure that these are not the sources of problem."

Scary stuff. That’s like taking a shotgun, aiming it under the hood, pulling the trigger and replacing whatever is hit with buck.
Unconscionable for a professional, I think.

When you say it ‘loses power’, do you mean that the car just starts to slow down or do you mean that it shuts down? I ask because then you say that the car restarts when you replug the coil wire.
The ignitor basically is a switch, much like the points used to be.
One side goes to ground, the other goes to one side of the coil. Since the other side of the coil is tied to +12V, the coil it quickly turned on/off which creates the high voltage on the secondary side that goes to the plug. Usually that’s how ignitors are wired, sinking the current.
Some may actually drive 12V to the coil (‘sourcing the current’) and the other side of the coil is tied to ground but the principal is the same.
You’ll have a difficult time measuring this pulse train because it is fast - a multimeter is too slow.
Ideally, you need a scope to see what’s going on. The pulse train may not be there or perhaps it is not the right shape when it acts up.
You seem comfortable around wiring so you may want to dig a bit deeper. Do you know anyone with a scope?

In lieu of that, you could make a fixture to see whether that train is coming with a 2K resistor in series with an LED. Assuming your ignitor is sinking the current, tie the resistor to the anode of the LED, the other side of he resistor to the primary (ie input) of the coil. The cathode of the LED to ground.
With the car running, you should see the LED light up kinda dimly. It may actually seem to dim further or turn off with higher revs. If the car doesn’t start, crank it and look at the LED. If it isn’t on, it is due to the ignitor, whatever drives the ignitor or the 12V isn’t there.

This site has a schematic to your car:
http://www.powerlibrary.net/Remote/Remote.asp?ID=Monroe
To get in, enter barcode 02378001078755

Edit: have you checked your ignition switch? One pole applies 12V to your coil. Next time it doesn’t start, measure common of the coil and see if it has 12V there.
If it doesn’t, trace it back and make sure you have a good connection. It could very well be that your ignition switch is bad.

AutoZone can check the ignitor for you, but it has to be removed first. I’m afraid that in your case, a new ignitor is not going to fix your problem. If you are approaching 200k miles on this car (or more), then you could have a worn distributor shaft bushing.

Remove the distributor cap. Crank the engine until a vane on the shaft lines up with the thin line on the ignitor. Stick an 0.010" feeler gauge in the gap, if you have a feeler gauge with a brass 0.010" in the set, use the brass one. With the feeler gauge in place, push on the distributor shaft to see if you can open the gap. If it opens to more than 0.007", that is a total gap of 0.017, or more, you need a new or remanufactured distributor.

The distributor is easy to replace and should cost about $300 or less. I prefer the NAPA remans for this. If you replace it, be sure to turn the engine till the timing marks line up TDC on #1 before you remove the distributor. Note how the rotor turns as the distributor comes out. If it comes straight out, putting the new one in will be almost fool proof. If it turns, then put something on the head where the rotor point to as it comes out, then use that mark for aligning the rotor when you install the new one. Verify that in the end, a vane on the shaft is almost directly across from the line on the ignitor and the rotor points to the #1 post on the cap.

When the car looses power the check engine light comes on and it display error P 1300, Igniter Circuit Malfunction (No. 1)

So you are seeing 12V on one side of the coil?

If you do what Keith recommended replace the O ring at the base of the distributor shaft assembly when you pull out the distributor. I did this before on the same model year 1996 Camry 2.2 liter engine of mine when I found oil leaking around this area. The distributor fits only one way at the driver’s side end of the camshaft. It is vertically slotted at the driver’s side end of the camshaft in an asymmetric fashion so it is impossible for you to put the distributor position incorrectly, even 180 degrees off.

Just tested the Igniter at Autozone. It is good. I am checking the distributor right now. I have also notice that the car dies when it engines is over 2000 RPM.

RemcoW, Thanks. Just check the coil and the igniter for 12V. Both have 12 V as needed.

I agree with the others…hit up a salvage yard and buy a distributor…or go on ebay…I believe there are very reasonable NEW units on there… You can buy the ignitor individually I think. I have replaced many of the removeable types with a 100% success rate… (When I properly ID’d the issue to be the ignitor) See what you can find on ebay. Forget the ECU…theyre dreamin… Dreamin of a big boat payment that is. ECU’s RARELY fry…and I mean RARELY… The most common issue in Yota’s is that ignitor.

Blackbird

Does this distributor have the coil piggybacked on it or is the coil separate? Since the cut out occurs above 2000 rpm, it leads me to suspect two items that are pretty cheap. If the coil is piggy backed, then the “coil wire” is built into the distributor cap. It could have gone bad. The other thing is the rotor itself but my experience with these is when they fail, which is very rare, they short through to the distributor shaft and it is not intermittent. Once they short out, they never work again, but it is possible.

The igniter checks out but for how long? Remember; it works but not for long. It runs the car for a little while then quits, so consider changing it.

1 Like

Thanks to y’all for the great help. I will be pulling the distributor today to make sure that it is good. Keith, I can not check for the gap in the distributor as suggested by you as the igniter on this car is not a part of the distributor. It is mounted outside the distributor right next to the coil.

Pleasedodgevan2, Thanks for the note. I have tried with a new igniter to no avail. It did the same thing. Once the old igniter was replace with a know good new igniter, the car died within 5 minutes.
I also check out the distributor today. It is good and does not have any worned bearing. While the distributor was out the o ring behind it was replaced to keep the oil from leaking.
I also checked out the primary 12 v to the coil. When the car died, it still have 12 volt to the primary. This was checked with a 12 v LED wired between the 12 v of the primary to the coil and the ground.
I am not going to let a 16 year old car beat me. I am going to win this battle. I thank you all for the help and please stay with me. Together we can do it.

This car should have OBD2 and might have some codes to read. The battery cables might be damaged or chafing too. This kind of checking may seem basic but you’ve looked in a lot of places. Sometimes it’s a simple thing that stops a car from running.

We could say anything and maybe guess right. Crankshaft sensors and things like that can stop the ignition from working.

@pleasedodgevan2 has a good point. While you’re seeing 12V on the coil when it dies, that may only prove that the positive cable to the battery doesn’t have an issue but it doesn’t exclude the negative cable as an issue.
Perhaps do that same test again, but put the negative cable on a bare part of the engine. If you still see 12V, it will eliminate the negative cable as a possibility.

It’ll be tricky to detect without a good scope but you want to know whether the pulse to the ignitor is dying before the pulse from the crank.
In a previous comment, I mentioned that just replacing parts is usually a bad idea but this may be the exception: unless you have access to a decent scope, if you can get your hands on a known good crank sensor to try, it may not be a bad idea…

If the ignitor is outside the distributor, then engine must have either a crankshaft position sensor or a camshaft position sensor or both. It will be bad.

Just checked the voltage at the 5 pin plug of the igniter. At pin 1, White/red wire, it has 4.9 volt and at pin 2, the white wire, it has .4 volt while cranking the engine. So ECM appears to be alright. I will check the camshaft position sensor and the crankshaft position sensor to get additional test data. I also placed a negative cable in paraller with the present negative cable. It did not keep the car running. As usual it stopped after about 5 minutes.

Did you ever find the root cause of the problem? I too have a 96 Camry and am experiencing similar symptoms.