3FE Died While Driving, Cranks Hard, No Spark, No Start (1 Viewer)

[Surfteerex]

Remind me, did you already try a known working ignition coil?

I have not yet tried a known working ignition coil or ignitor yet, but resistance of primary and secondary ignition coils tested within FSM spec, and there seems no way to test the ignitors that i can tell. But I am getting a little bit of spark from high tension cord to sound when cranking...

 

[jonheld]

4) Checked resistance at distributor pickup coil - OUT OF SPEC PER FSM: 229 OHMS (FSM SAYS REPLACE DISTRIBUTOR IF NOT WITHIN 140-180 OHM RANGE)

I question your reading here. A coil will open or short, not increase in resistance. Are you testing this at the distributor plug or back at the ECU?
In a very early post on this thread I suggested replacing the igniter and this has been suggested by others several times. Igniters go bad on these trucks and there is no FSM procedure for checking them.

 

[Surfteerex]

I question your reading here. A coil will open or short, not increase in resistance. Are you testing this at the distributor plug or back at the ECU?
In a very early post on this thread I suggested replacing the igniter and this has been suggested by others several times. Igniters go bad on these trucks and there is no FSM procedure for checking them.

@jonheld I just put in a known good ignitor off eBay (Car tested, excellent review from seller), turned key, cranked hard and no start. Also, to answer your last question, my reading of 229 ohms at the distributor pickup coil was at the distributor plug per FSM diagram. Does that make any difference in your take?

 

[Surfteerex]

UPDATE:
Alright everyone, pull up a chair and a cup of coffee, and bear with me as I try not to throw in the towel on this mission and just have the cruiser towed to a shop to deal with. I feel like I'm getting closer, but also at whits end without the cruiser running, and still have a million questions and uncertainties. Here it goes:

TESTS I RAN/RE-RAN TODAY:
1) Tested for spark using the Dorman in-line tester recommended by @SUMMIT CRUISERS in a past post on this thread, and per past comment from @Pin_Head of unreliability of shade tree mechanic spark testing, and got NO SPARK AT ANY PLUG (tested all 6) while cranking. ZERO SPARK. It is definitely my issue, or at least one of them.

2) Retested primary ignition coil resistance: .4-.5 ohms (NORMAL, within FSM spec)

3) Retested Secondary Ignition Coil Resistance: 9.96 k Ohms (ABNORMAL, FSM says replace if not within 10.2 - 13.8 k Ohms). Could this produce weak spark test at end of high tension cord mentioned below? and ZERO spark at plugs? @jonheld @Eicca @Pin_Head @SUMMIT CRUISERS

4) Rechecked distributor pickup coil resistance using wire harness outside of distributor (and distributor side of that harness when unplugged), and confirmed my past results: G to G(-) = 227.9 ohms, and NE to G(-) = 227.1 ohms
@jonheld you questioned my reading here last time, but I think I am performing the test correctly. In addition, i noticed that this reading would be WITHIN normal spec according to your document (you report range between 140 -1800 ohms, which seems large), but is OUT OF SPEC according to my FSM, which calls for normal range of 140 - 180 ohms. Do you think you maybe just accidentally put an extra zero on your doc? Am I in or out of range here?

IGNITOR:
1) I have installed a known good ignitor (using superseded part #89621-12010 per @george_tlc prior suggestion on this thread), purchased off eBay from a well reviewed seller who reported it was vehicle tested. This produced NO EFFECT, cruiser still won't start, and no change in strength of spark upon spark test at high tension cord.

SPARK AT DISTRIBUTOR END OF HIGH TENSION CORD:
1) After new ignitor installed, still EXTREMELY WEAK upon spark test. I literally have to hold the center prong of the distributor-end of the high tension cord TOUCHING a ground bolt to see a TINY TINY TINY arc, and is similar to how the test played out with old ignitor installed. This arc cannot jump a 1.1 mm / .043 inch gap that the plug is gapped at per FSM, or jump any gap at all in my case. Does this seem weak to anyone?What might cause a weak arc here? Ignition coil possibly? @jonheld @Eicca @Pin_Head

2) Can someone with my same 91 cruiser 3FE (except running of course) please run the spark test at the end of the high tension cord (mentioned above, and see how far a gap this arc can jump, if any? Test literally takes 1 minute, you need 2 people: Unplug center wire from distributor (that connects to ignition coil), hold prong of now disconnected end near ground bolt on frame (small gap, maybe 1-2 millimeters), and try to start the cruiser while observing the arc. Does it arc with ANY gap at all or do you literally have to touch prong to ground bolt to observe tiny spark?

THINGS I HAVE NOT DONE/TESTED YET, AND I THINK MAY BE RELEVANT:

1) I have not checked continuity from distributor pickup coil backo ECU. I tried today, but FSM says not to unplug harnesses and to read ECU resistance by inserting prongs into wire side of harness. This seemed literally impossible. Is it ok to unplug wire harnesses from ECU to check for continuity? Or how else could I do it? Also, what setting on the multimeter do i use to check continuity between distributor and ECU @jonheld ? Im assuming connecting from wire harness pin on ECU end to wire harness pin at distributor end? Is that correct as well @jonheld , and what setting on multimeter?

2) I have not checked the air gaps inside distributor using a feeler gauge/thickness gauge, as suggested by FSM.

Would these two tests be worth while pursuing, considering all else?

MY THOUGHTS IN SUM:
I THINK ITS A NO SPARK ISSUE, I THINK THE IGNITOR(S) I HAVE BOTH WORK AND ARE NOT THE PROBLEM, I THINK THE SECONDARY IGNITION COIL IS OUT OF SPEC AND MAY WARRANT REPLACING IGNITION COIL, I THINK THE DISTRIBUTOR PICKUP COIL RESISTANCE IS OUT OF SPEC AND MAY WARRENT REPLACING, AND I STILL DONT KNOW ANYTHING ABOUT CONTINUITY BETWEEN DISTRIBUTOR AND ECU, OR BETWEEN ECU AND ANY OTHER PART REALLY.

Any thoughts on all/any above are greatly appreciated. Not giving up yet, but I really wish I would already Trying to avoid the tow truck call/mechanic bill/more extraneous parts best I can. PLEASE HELP!!!!

 

[Eicca]

How's your voltage supply to the ignitor (assuming "ignitor" means the black box that sits above the wheel well. Not sure why I'm suddenly unsure of this).

To answer your question of how strong the spark should be from the ignitor, I was doing something with the engine running once, don't remember what, and this guy thought he'd be funny and try to unplug the wire that runs from the ignitor to the distributor. The sparks were so big he couldn't grab hold of the line. It was quite funny. All he had to do was touch it and there were very large and very visible sparks jumping out of the socket.

Having a very weak and barely visible spark coming out of that high tension line is highly suspicious. Like I mentioned above, if both ignitors are good, I would check the power coming in to them.

 

[SUMMIT CRUISERS]

Sounds like your igniter/coil pack or distributor has gone bad. I would inspect your distributor pickup coils for corrosion. This is an easy visual check and if they look bad, they either need to be changed (sourced from a salvage yard only) or change the distributor. If your distributor cap does not have the vacuum ports or does and the vacuum hoses were not hooked up properly, your pickup coils are probably corroded.

Maybe I missed it but Is your distributor cap OEM with the vacuum ports? If not, I've seen pickup coils go bad within a year with a no spark situation. Inspect pickup coils for corrosion?

 

[george_tlc]

The distributor pickup coils provide the ECU the information necessary to fire the igniter which provides the drive signal to the coil.

And yes, corrosion of the pickup coils is possible if water/oil contaminants are allowed to sit in the distributor.

Unfortunately with EFI engines, there's a bunch of things that ALL have to work to get a quality spark fired at the correct time.

cheers,
george.

 

[Pin_Head]

The coil doesn't sound far off, but it is easy to test. Remove wires at the - side, turn key on, momentarily ground the - side and check for spark. If you have a big fat spark, then the igniter / pick up is bad.

 

[Surfteerex]

How's your voltage supply to the ignitor (assuming "ignitor" means the black box that sits above the wheel well. Not sure why I'm suddenly unsure of this).

To answer your question of how strong the spark should be from the ignitor, I was doing something with the engine running once, don't remember what, and this guy thought he'd be funny and try to unplug the wire that runs from the ignitor to the distributor. The sparks were so big he couldn't grab hold of the line. It was quite funny. All he had to do was touch it and there were very large and very visible sparks jumping out of the socket.

Having a very weak and barely visible spark coming out of that high tension line is highly suspicious. Like I mentioned above, if both ignitors are good, I would check the power coming in to them.

@Eicca I know the battery is at 12.3 volts, but i haven't tested voltage to the ignitor. Anyone have a way to test this? I will try to eyeball around tomorrow and see if i can find a way to test it as well, but any guidance would be appreciated!

Maybe I missed it but Is your distributor cap OEM with the vacuum ports? If not, I've seen pickup coils go bad within a year with a no spark situation. Inspect pickup coils for corrosion?

@SUMMIT CRUISERS old distributor cap was not OEM according to @jonheld , but it did have vacuum ports, and the new cap i put on is OEM with vacuum ports. I will take the distributor cap back off tomorrow and take a look at the pickup coils, as well as measure the air gap while I'm in there. Keep you posted here...

The distributor pickup coils provide the ECU the information necessary to fire the igniter which provides the drive signal to the coil.

And yes, corrosion of the pickup coils is possible if water/oil contaminants are allowed to sit in the distributor.

Unfortunately with EFI engines, there's a bunch of things that ALL have to work to get a quality spark fired at the correct time.

cheers,
george.

Thanks George. Im going to inspect the pickup coils a little more closely tomorrow and let you know how those look... @george_tlc

The coil doesn't sound far off, but it is easy to test. Remove wires at the - side, turn key on, momentarily ground the - side and check for spark. If you have a big fat spark, then the igniter / pick up is bad.

@Pin_Head which coil are you referring to? the ignition coil or the distributor pickup coils? Also, I may be misunderstanding but both of those are supplied via a wire harness, where + and - come in together, correct? How would i remove negative?

THANKS ALL!!!

 

[jonheld]

3) Retested Secondary Ignition Coil Resistance: 9.96 k Ohms (ABNORMAL, FSM says replace if not within 10.2 - 13.8 k Ohms).

If the coil is out of spec, then I would replace it with a used/known good one. While I've not heard of an ignition coil failing on a 3FE (it's almost always the igniter that fails) a low secondary coil resistance indicates possible shorted windings. If that's the case, then during a spark cycle it could be arcing internally.

 

[jonheld]

4) Rechecked distributor pickup coil resistance using wire harness outside of distributor (and distributor side of that harness when unplugged), and confirmed my past results: G to G(-) = 227.9 ohms, and NE to G(-) = 227.1 ohms
@jonheld you questioned my reading here last time, but I think I am performing the test correctly. In addition, i noticed that this reading would be WITHIN normal spec according to your document (you report range between 140 -1800 ohms, which seems large), but is OUT OF SPEC according to my FSM, which calls for normal range of 140 - 180 ohms. Do you think you maybe just accidentally put an extra zero on your doc? Am I in or out of range here?

Please keep in mind that I did not write the 3FE FSM
However in comparing the spec of the distributor pick up coils between the 1991 FSM and the 1996 FSM, there does appear to be an extra zero in the 1991 version, but I don't know for certain and I'm not going to second guess Toyota right now.
The 1991 version that I have in my documentation is one I downloaded from Toyota publications years ago. I'd like to compare that to the original printed copy. If I get a chance to do that today I'll let you know.

A better idea is to compare it with the FSM for an FJ62. They use the same distributor.

Again, coil windings don't magically increase in resistance. It's a length of wire wrapped around a ferrite core. Windings can short (lowering the resistance) or open. It is not likely that they slightly increase.

It is possible that the connection points have corroded causing higher than normal resistance. This is why I asked you to check continuity back to the specific pins on the connector of the ECU in a prior post, or simply compare the resistance readings that you get between the ECU connector and the distributor housing. The 2 readings should be within 1 or 2 ohms of each other.

 

[jonheld]

A better idea is to compare it with the FSM for an FJ62. They use the same distributor.

According to the FJ62 FSM, the pick up coil resistance should be 185 to 265 ohms.
Both versions of the 3FE use the same distributor, same part number. So there does seem to be a discrepancy between the 2 FSMs. I'm waiting on a buddy of mine to get back to me regarding the hardcopy version of the 1991 FSM, but at this point I would say that 1800 ohms is a misprint.

 

[jonheld]

Just got a picture of the page from the 1991 FSM and the spec reads 140-180 ohms so for some reason the downloaded version is incorrect. I will update my docs.

 

[Pin_Head]

I was talking about the ignition coil. You know, the one that makes the spark and has + and - labels on the terminals.

 

[LAMBCRUSHER]

For testing continuity at the ecu, paperclips can be back-probed into the terminal slot of the wire you're trying to read, then the test leads can be clipped to the paper clips...HTH

 

[Tools R Us]

Have you done the power checks? The + side of the coil, injectors, igniter, etc, should have close to B+ voltage with the key to run. IIRC, they are all black w/green stripe.

 

[Surfteerex]

Here's what I did today to answer some of the last questions:

1) Confirmed valve lifters move when cranking via visual inspection through oil filler cap (to answer an old question from @Pin_Head, but we are not suspecting compression any more - focused on spark). I could not run the ignition coil test you recommended today @Pin_Head because + and - come into the primary coil together through a harness, so i cannot disconnect - to test to ground. Any suggestions here?

2) Confirmed voltage to ignitor and ignition coil when ignition is in "ON" position, getting nearly 12 volts to each, so thats good. Couldn't figure where to check for voltage to injectors as wires seem hard to get to, but I'm alright with that. GOOD TO GO HERE. @Eicca @Tools R Us

3) Confirmed continuity from ECU-side of distributor harness back to ECU using paper clips to back-probe wires at ECU, per @LAMBCRUSHER recommendation (thank you by the way!). It was difficult, but all 3 wires tested out well. GOOD TO GO HERE. @jonheld

4) Confirmed air gaps between both G and NE pickups inside distributor were within spec (.279mm and .330mm respectively, and spec is between .2 - .4mm per FSM). GOOD TO GO HERE. I also inspected for corrosion at both the pickups inside the dizzy, as well as for corrosion at harness on the outside of the dizzy, and both seemed in fair shape. Please see pictures attached of both pickups and harness, and confirm or deny my thoughts @george_tlc @SUMMIT CRUISERS @jonheld , but otherwise, GOOD TO GO HERE. I was trying to confirm continuity from pickup coils to dizzy-side of harness going to ECU, but couldn't figure out a way to do that. Any thoughts on that?

I also tested resistance of ECU-side of distributor harness per @jonheld suggestion, and both G to G(-), and NE to G(-) put out 6.95 K Ohms, so they were the same. But the distributor-side of distributor harness put out 223 and 224 Ohms (re-re-re-tested and re-re-re-confirmed today).

In addition, I was fortunate enough to be able to run a spark test on a RUNNING 1996 TLC (different parts than my 91, because i was hoping to try his ignition coil in mine but couldn't) at the distributor-end of the high tension cord, and his rig put out a MUCH MUCH MUCH MUCH MUCH LARGER AND STRONGER SPARK when placed near a ground bolt, arcing across about a half inch gap with a strong arc! Remember, mine won't arc across any gap AT ALL, and produced TINY TINY TINY sparks when TOUCHING the ground bolt and trying to start the motor.

With all this said and done, I am thinking 2 things are possible causes:

1) Ignition coil failure because of A) reduced spark at high tension cord upon spark test, B) No spark at plugs using inline spark tester, and C) Secondary coil resistance is out of spec per FSM (reads 9.96 K Ohms and spec calls for 10.2 - 13.8 K Ohms) D) High tension cord spark test on 94 TLC produced STRONG arc about 1/2 inch to ground, while mine cannot jump a gap and produced TINY arcs while directly touching ground bolt

OR

2) Distributor failure somewhere between wire harness and pickup coils inside distributor. Dizzy-side of wire harness tests higher than spec for resistance (not sure why or how this is happening, but it is). FSM says 140 - 180 Ohms, and I've repeatedly tested 223-224 Ohms. This is also a little suspicious as @jonheld has reported the FJ62 using the same distributor and its FSM calling for a resistance range of 185-265 Ohms, which would make my reading WITHIN spec

PLEASE give me your input on any other tests i can/ought to run to better guide my decision making, or if you'd go for one or the other (or something else) based on all the results I've already gotten.

Thanks so much guys, hopefully we get there soon!

 

[Pin_Head]

Measuring 12V doesn't mean anything if the circuit is open. You would get 12V even if you had a 10,000 ohm resistor in line. You need to measure when the circuit is complete. Ignition coils rarely fail, but they are cheap. It is more likely the igniter and or pickup. If you can't disconnect the - side or the ignition coil, just try grounding it.

 

[Surfteerex]

Measuring 12V doesn't mean anything if the circuit is open. You would get 12V even if you had a 10,000 ohm resistor in line. You need to measure when the circuit is complete. Ignition coils rarely fail, but they are cheap. It is more likely the igniter and or pickup. If you can't disconnect the - side or the ignition coil, just try grounding it.

@Pin_Head how do you recommend i measure when circuit is complete? Also, how do you recommend i ground the ignition coil to perform that test? Keep in mind your talking to a relative NOOB . Also, I have a second "known good" ignitor installed now, and it didn't do the trick. Still producing extremely week spark at end of high tension cord, and no spark at plugs...

 

[Pin_Head]

When you ground the - side of the ignition coil, the circuit is complete.