86smiley

Sorry, but this came up in a different thread.

My mechanic has told be that I have a weak spark and it is the Ignitor Module (or ignition assembly) on a 1986 Toyota 4x4 22RE that is failing. This also cause the injectors not to fire..... ie therefore no gas into the cylinders.

Is it just me, or does this make no sence????

Can anyone shed light on the firing of the injectors?

Thanks

fireman1559

hmmmm that doesnt sound right when mine went out i could smell the fuel but was getting no spark and when mine went out there was no warning to it at all it just died going about 45mph down a back road(thank goodness) so it might be something else

ScottyC

iTrader: (1)

Yes, that is what can happen when an ignitor fails.

myyota

A weak spark can be caused by a bad coil, try replacing the coil and see what happens, because a coil is a whole lot cheaper than an ignitor. The last time i checked the price of a new ignitor it was in the 350-400 dollar range, unless you get lucky and find a good used one.

abecedarian

Considering that the only information the ECU gets about the engine 'turning' comes from the distributor, to the igniter, then to the ECU... what's so hard to believe?
Keep in mind that the igniter fires the plugs when starting the engine without any control from the ECU, sends distributor position signals to the ECU (NE signal) and even sends a signal to the ECU about cylinder combustion events - spark plug fired or fouled (IGF).
If the igniter is failing, any one of those signals could be sporadic yet not be failing 'enough' to cause the ECU to not fire injectors... and may even cause the ECU to fire the injectors multiple times.

86smiley

Just found a used Ignitor tonight. Left it for my mechanic to swap out tomorrow ( I have to be a work... gotta pay for this stuff some how )

so what the mechanic is suggesting is reasonable? I guess I will find out tomorrow for sure....

fireman1559

im curious about this now so does that mean that a weak spark can cause the injectors to not send fuel to the motor?

86smiley

abecedarian- what if there is no gas present on the spark plug after turning it over several times and pressing on the gas? Is should be flooded...no? and the plug should be "wet" if the injector was firing. ...just asking.... I am definately no mechanic.

Thanks for all the input so far

abecedarian

Nope. If the ECU doesn't get the signal from the igniter, it won't fire the injectors regardless on the foot on the pedal.

abecedarian

Maybe I should add that with a cold engine, below about 60-65F, the cold start injector should be firing and that could cause wet plugs if the plugs aren't firing.

fireman1559

ahhhh ok makes sense now

Kiroshu

Yea the whole system is in sync for the engine to run. A fouled or cracked distributor can cause weak spark too... old and cracked plug wires? fouled out plugs? Bad coil? igniters usually last a long time and don't go out much. i've had luck tapping on them if they are acting up and they stop...

Aubs

Here's the story: 2 months ago I had my friend (toyota mechanic by trade) do the heads on my '92 3vze 4x4. Before that it sat in my garage for 5 months warm and cozy.

All good until 2days ago when it died just like i had turned the key off. It started for a few seconds then died again. So to get me off the road i put it in 1st and turned the key to bump me out of the way. I noticed that it would crank with out the clutch or the cancel button pushed in (wrong). I got no warning lites. So 10 minutes later i can't crank the engine unless the it's pushed in (as it should be), and it fired up just fine for about 5 seconds, then died. So, when the button works so does the engine. when it don't then engine won't.?! Coil? distributor? The button? Ignition switch?

Where's the cheapest place to start? I can do the work no problem.

Thanks

Jay351

Cheapest way to start it to test things.

Test everything you can, coil and igniter (to be safe), AFM.... Did mice have at your rig when it was sitting in the garage??

Aubs

i will be testing everything once my buddy is done with his Multi-meter.

Im not done lookin yet....but no mouse marks yet.

What ohms, volts range is ideal? How much should the coil read (for eg.)?
I just soaked my chiltons guide, so its not readable. oops

thanks.....Rock on and Throttle out!

86smiley

Just an update:

On Friday, I stopped by the mechanics place to have the truck towed to another "Toyota Mechanic" for more diagnostics. When I got there, they were testing the fuel pressure (thought that they had done this already...).
Only running about 10 to 13 pounds of pressure..

Dropped the tank again, changed the fuel pump and the truck started right up.

I have noticed since Friday that it takes about 3 to 4 seconds of turning over before it catches... maybe still something not working right... But for now I have a running truck.

Thanks for all the input from everyone. I will post some pic's after i get the box repainted..

cheers
86smiley

Aubs

Awsome, I love a happy ending.