HELP!!! No Spark. Pulling Hair Out!! Please...
- Thread starter kgriff
- Start date
LOL. We talked about needing something like that. We don't. I'm just whining. I have shade part of the day from trees. Unfortunately, the best shade is morning and evening when it's cooler anyway.
I guess I assumed you had already messed with the MAF but yeah... so... I would swap MAFs THEN try swapping cam sensors
Cam sensor swapped with T100. No Go.
As a point of interest, and something else I've learned today, the T100 fired right up with the cam sensor unplugged. Probably wouldn't have ran well, but idled just fine.
On to tracking grounds, I suppose.
And rechecking all fuses.
And rechecking all relays.
And looking for some elusive fusible link or fuse that somebody, sometime, maybe, installed for some silly reason that I can't fathom.
19963.4lsr5
New member
Your scanner talking to the 4Runner even if it won't start at least indicated the ECU isn't dead.
The ICM grounds the coil power is always on the plus side.
Somewhere there is a engine state signal telling the PCM the engine is cranking. It's terminal STA of ECU
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The ICM grounds the coil power is always on the plus side.
Somewhere there is a engine state signal telling the PCM the engine is cranking. It's terminal STA of ECU
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Can you explain what you mean by "The ICM grounds the coil power is always on the plus side."?
I'll take a look at STA on the ECU and see what I can see.
I did find one slight anomaly.
Measuring power to the ECU...one terminal is always 12V, another is 12V with Ignition ON. They are measuring around 11.83. Battery voltage measured at the battery is currently 12.01. Is this enough of a difference to be concerned about?
I have located every ground strap I can find, ohmed back to battery negative, all look good. ECU case to battery negative looks good.
19963.4lsr5
New member
I've used that port to get the abs lights to flash to show why it was on.
The ECM grounds the coil to start the spark process. When it removes the ground the spark happens. It takes milliseconds.
Look for the start input, it should be hot when the small wire to the starter is energized by the starter relay and the starter is turning over the engine.
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The ECM grounds the coil to start the spark process. When it removes the ground the spark happens. It takes milliseconds.
Look for the start input, it should be hot when the small wire to the starter is energized by the starter relay and the starter is turning over the engine.
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STA on the ECM is as it should be.
I actually went through every ECM terminal that I could without the engine running and all checked OK.
I've got 0.2 Ohms higher resistance when measuring from the ECM gnd terminal directly back to battery negative than I have when measuring test leads shorted together. Seems like a reasonable number to me. The only thing I could do to confirm is measure the T100 resistance the same way and see if it's equivalent.
I'm reduced, at this point, to having my wife crank the engine over while I tug, pull, and bend wiring to see if I can identify an open somewhere.
I'm still trying to figure out if one of the added on things could do this. All I have that's not bone stock is the VIP security and an aftermarket stereo. Looking at the stereo wiring though, I'm not terribly thrilled with whoever installed it.
Finally, I went through all the fuses again and all are good.
I'd like to take a moment to thank everyone who has offered ideas and suggestions.
I actually went through every ECM terminal that I could without the engine running and all checked OK.
I've got 0.2 Ohms higher resistance when measuring from the ECM gnd terminal directly back to battery negative than I have when measuring test leads shorted together. Seems like a reasonable number to me. The only thing I could do to confirm is measure the T100 resistance the same way and see if it's equivalent.
I'm reduced, at this point, to having my wife crank the engine over while I tug, pull, and bend wiring to see if I can identify an open somewhere.
I'm still trying to figure out if one of the added on things could do this. All I have that's not bone stock is the VIP security and an aftermarket stereo. Looking at the stereo wiring though, I'm not terribly thrilled with whoever installed it.
Finally, I went through all the fuses again and all are good.
I'd like to take a moment to thank everyone who has offered ideas and suggestions.
19963.4lsr5
New member
So if you put a test light on the STA the bulb lights up when starter is cranking the engine?
On the coil connectors the Red for coil 1 should pulse. The Brown With White should pulse for coil 3 and the Orange should pulse for coil 2. The black with red wire on each coil will always have battery voltage applied as long as the ignition is on.
It be nice to see the wiring for the factory alarm.
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On the coil connectors the Red for coil 1 should pulse. The Brown With White should pulse for coil 3 and the Orange should pulse for coil 2. The black with red wire on each coil will always have battery voltage applied as long as the ignition is on.
It be nice to see the wiring for the factory alarm.
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Last edited:
19963.4lsr5
New member
When you checked the timing the crank sensor lined up with the pulley, correct?
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gamefreakgc
Elite Member
That's just normal voltage drop. All the wires/connectors etc. add a tiny bit of resistance along the way. Try measuring the voltage from the battery to the headlights and you'll really start to see the voltage drop!
I wasn't surprised at the voltage drop, just didn't know how touchy this vehicle would be about it. On older vehicles, I'm used to seeing as much a half volt drop from one point to another.
SHE'S RUNNING.
Thanks to a PM from CB3G_GM that got me headed in the right direction. He suggested that, if the crank sensor I replaced was aftermarket, it could either be a bad part, or just not satisfying the ECM.
I reached down to unbolt the crank sensor and, lo and behold, it was spinning freely in the mounting bracket.
After I had installed it, the little mounting ear had broken, allowing the sensor to back out. (I know it didn't break while I was installing it because I connected the electrical connector AFTER it was mounted in place.)
Yes, it was an aftermarket part. The Toyota dealer didn't have them in stock, so I went aftermarket, against my better judgement.
Along those lines, I would recommend ALWAYS buying timing and water pump components from the dealer. When I did the timing belt on my 97, I got to do it 3 times because of bad aftermarket parts. Third time I waited for the dealer to get parts in and, how about that, everything was good.
Next to lastly, how do I change the title of the post so it can say, "Solved"?
And finally, I want to throw out a huge thank you and figurative case of beer to everyone that had thoughts, ideas, suggestions. I may have gotten there on my own eventually, but thanks to all you guys, I got there much quicker.
Thanks to a PM from CB3G_GM that got me headed in the right direction. He suggested that, if the crank sensor I replaced was aftermarket, it could either be a bad part, or just not satisfying the ECM.
I reached down to unbolt the crank sensor and, lo and behold, it was spinning freely in the mounting bracket.
After I had installed it, the little mounting ear had broken, allowing the sensor to back out. (I know it didn't break while I was installing it because I connected the electrical connector AFTER it was mounted in place.)
Yes, it was an aftermarket part. The Toyota dealer didn't have them in stock, so I went aftermarket, against my better judgement.
Along those lines, I would recommend ALWAYS buying timing and water pump components from the dealer. When I did the timing belt on my 97, I got to do it 3 times because of bad aftermarket parts. Third time I waited for the dealer to get parts in and, how about that, everything was good.
Next to lastly, how do I change the title of the post so it can say, "Solved"?
And finally, I want to throw out a huge thank you and figurative case of beer to everyone that had thoughts, ideas, suggestions. I may have gotten there on my own eventually, but thanks to all you guys, I got there much quicker.
19963.4lsr5
New member
That she is.
theesotericone
New member
Both. LOL
Figured out thanks to all the nice folks here. What a great bunch of folks.
