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Hi everyone, just want to say thank you in advance. This forum has been very helpful to me. I am a first-time Toyota owner whose mechanical experience is limited to oil changes, spark plugs, distributor cap and rotor, and plug wires. I've always wanted a Toyota, this is my first one.
I couldn't find the answers through my google and forum searches. So I decided to post a thread. I will keep the post as concise as possible.

I have had the truck about 2 months.
It is an 1987 Toyota Pickup with 3VZ-E 3.0L. Toyota tells me that based on the VIN, that the truck was originally sold with the 4cyl 22R-E. It was also sold to me as an 88 but the badge on the door jam says manufactured September 86.Toyota told me it's an 87. I understand that the truck would be sold as the next-model-year. So 87 makes more sense to me than 88. Anyway..

Here is the nutshell --
Because there is no spark to the plugs, which was found by a mechanically inclined persons's troubleshooting, I followed the instructions on how to test the ignition coil using a test light. I connected the test-lead alligator clip to the positive battery terminal and then touched the probe to the negative terminal on the ignition coil. A green light turns on inside the test light. When I have someone crank the engine, the light turns off and stays off while the engine is cranking.and stays off when finished cranking
My question is, based on that test result, where should I look to next? I read somewhere that this indicates the problem is before the coil?
I have replaced the rotor inside the distributor (it is in pretty rough shape, worn down and covered in corrosion) - no change
I replaced the distributor cap - no change
I put the old distributor cap back on because it looks just like the new one so I assumed its ok and wanted to return it to save the money
I replaced the 12v ignition coil - no change (i haven't had the new cap on with the new ignition coil..)
I checked fuses
I was told to check for fuel pressure at fuel rail by cracking the bolt at the fuel rail - fuel bled out when the bolt was cracked open

Spark Testing:
Screwdriver inside spark plug boot --> screwdriver close to engine ground --> have someone crank --> no spark (same with spark plug inside boot)
Removed high-tension cord boot off the ignition coil --> attached test-light alligator clip to negative battery terminal --> placed test-light probe real close to ignition coil --> have someone crank --> no spark
Moved test-light alligator clip to positive battery terminal and touched probe to negative terminal on ignition coil --> light comes on --> have someone crank --> light turns off and stays off while cranking and stays off when stop cranking

Here is how I got here, so as to give you all as much information as possible.

The truck would intermittently not start. It would always start with a jump. Other times, it would start if you just kept trying. In these instances during no start condition, you would turn the key and - nothing would happen. The lights are on in the dash, and the truck would blare its little internal siren noise saying "you're key's in the ignition" etc.. but there would be no engine cranking, like the truck hasn't reached that step in its start-up process. Anyway, the last time it failed to start, I checked fuses etc.. and ended up replacing the EFI Relay in the driver-side kick panel because it (even though it was pretty rusted) it wasn't showing any readings on my ohm meter. To be fair, I think I might have shorted that relay because I'm new to this. When I replaced it, it started right up when I replaced this relay. Now this is where I think a gremlin crawled in and died in the truck. I turned off the truck, then proceeded to pull out the battery to replace a ground wire that's going from the negative battery terminal to the fuse box inside the truck. Don't ask me why I did this.. someone said I should and so I did. The wire isn't actually going into the fuse box, its just attached to one of the screws that holds that fuse box assembly to the inside of the engine bay. When I put everything back together, the truck would not start. That was 4 days ago. I put the old ground wire back and still nothing. This no-start condition I am experience now is unlike the other times the truck hasn't started. Because it cranks and cranks yet doesn't turn over.

I should mention that a week ago, due to high and rough idle, I removed and checked the Throttle Position Sensor. I found that it would stick open or not close all the way due to gunk and grime. I cleaned it out. It mechanically works OK now, springing back into place. I had to adjust the TPS by "feel" because the marks I made wore off. Stupid sharpie, Before I readjusted the TPS, I had driven the truck around the block and found the truck would have hard acceleration after pressing the gas a little. So when I parked the truck, I would adjust the TPS to the point that the engine wouldn't have stuttering RPM when I pulled the throttle cable gently. The truck has worked fine up until my "no spark" issue.

Thank you in advance!

854x4

Lets deal with the known issue (NO SPARK) worry about the efi relay, dis cap , tps ,and fuel pressure till later. Go back to testing the coil put the test light clip to a good ground and probe the positive side of the coil, you should have 12v or a bright light. Have someone crank it while holding the light it might dim but should stay lit, if its stays lit then power to the coil is good. Since you have already tested the negative side of the coil and it doesn't flash then this usually points to a bad igniter, wiring or it can also be a bad distributor. The distributor sends a signal to the computer that the engine is cranking and then the computer relays that signal to the igniter telling it to fire the coil.

Capsulated

Thank you for your informative reply - the result of the test you suggested is that the light stays lit while the engine is cranking. I attached the alligator clip to ground and kept contact of the probe to the positive terminal on the coil. With the key in the on position, the light turns on. When cranking, the light stays light.

When checking the wiring, would you be referring to the wiring that is attached to the igniter? Unfortunately I don't have access to another distributor assembly or igniter at this time

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I checked the distributor for a rotating rotor - had someone crank the engine with the cap off and I could see that the rotor is turning. I wanted to test the pickup coils but i couldn't find the "how to" in the FSM - only what the readings should be. I've tried looking this up on the internet but they all seem to be different distributor from the one on my truck.

854x4

Try looking at this thread https://www.yotatech.com/forums/f2/n...89-95-a-10543/ it tells how to test the distributor pickups and the igniter.

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Thank you very much for this link - I have stumbled upon this one before but I was having difficulty understanding the information and where I should be connecting the leads. I am in the process of educating my self further on this so that I can actually test the pickup coils.

I stumbled upon this thread yesterday about no spark - https://www.yotatech.com/forums/f116...t-come-190314/ which grabbed my attention becauase I also don't have any check engine lights appearing. In the thread, way down near the bottom, the person mentioned the VAFM and how they pulled the silicon cover and noticed the pins were damaged, sitting across across each other and arcing. He replaced the VAFM and he got spark. I previously pulled the connector from the VAFM a few days ago because a video showed that if you pull the VAFM connector and start the truck, if it starts and dies then the problem (in that scenario) was the VAFM. I tried that but no change. I am wondering if I damaged the pins.. I do not want to peel the silicon cover to check because I don't know if that will damage the device. I'm pretty certain it will so I am leaving it alone. I am going to proceed to try and educate myself about diagnosing the pickup coils.

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The issue I'm having is colors are not matching up from what's in the thread VS what's on my truck but I may be interpreting this wrong. What I am interpreting is that I should be probing the terminals on the distributor's harness which is the tail end directly connected to the distributor assembly (the male harness). I do have these terminal colors listed below, but they are on the harness which is connected to the engine wiring (the female side). Additionally, the colors do not match from the thread to what I have on my igniter..

Thread states "Identify the terminals on the Distributor connector using the wire colors on the harness side.
Terminal-1: White..NE signal
Terminal-2: Red..G1 signal
Terminal-3: Black..G2 signal
Terminal-4: Green..G- signal"

The terminals on my distributor harness colors are Terminal 1-Red, Terminal 2-Green, Terminal 3-White, Terminal 4-Yellow
I have these numbered based on the colors they're plugging into on the female, engine-wiring side
Engine White to Distributor Red
Engine Red to Distributor to Distributor Green
Engine Black to Distributor White
Engine Green to Distributor Yellow

Lastly,

Thread states "Go to the Igniter, which should be mounted at the Coil. On the Igniter connector, locate the Black/Blue wire and probe into it with a test-light."

I do not have a Black/Blue wire on either the harness connected directly to the igniter (male connector) or the harness connected to engine-bay wiring (female connector)
I have on the igniter.. Brown, Yellow, Red, White
I have on engine-bay connector.. Black w/Red Stripe (to Brown), Blue w/White Stripe (to Yellow), Red (to Red), Black w/White Stripe (to White)

I apologize if my post has too much "red herrings" in it. I just wish to provide you with as much info as I'm looking at.

Thank you again for your help. It is sincerely appreciated.


.

854x4

Use the harness side wire colors to identify what wire to back probe or test on the part because a lot of times parts can have different color wiring. The distributor wire colors looks the same on both 88 and 94 diagrams.
On the igniter 88 wiring diagram
black/red stripe is ignition power
red is IGT terminal
black/white is IGF terminal
blue/white is Tach signal
you should also have a ground wire and then the wire from the igniter to the negative side of coil.

On the igniter 94 diagram
black/red is ignition power
black/blue is IGT terminal
black/yellow is IGF terminal
black is Tach signal
black/white to coil negative
doesn't show ground wire on diagram
Looks like the wire you want to (Tap Test) is the IGT wire which in your case should be the red wire.

Capsulated

Ok, the directions make sense to me now, thank you.
With the harness disconnected, I've checked the resistance between the wires on the distributor assembly connector based on their counterparts of the wiring harness.
If I've done the test right, the results don't look good for the distributor's pickup coils..
I set my digital multimeter to 200ohms and probed...
G- to G1 --- I was actually not able to get any readings at that scale. There was no change in the display. I set it to 2000ohms out of curiosity and got a reading of 309?
I tried this multiple times with the same results.
G- to G2 -- 154.8 (set to 200ohm scale)
G- to NE -- again, no reading at the 200 scale. Set to 2000ohm however, and I get a reading of 312
I went ahead anyway and tried the tap test after reconnecting the distributor harness and turned the ignition to on. I was unable to get a spark.
I had shoved a sewing needle into the igniter's red wire slot from the back-side of the connector. Is this why they call it back-probing? because you need to get readings/tests based on when the connectors are locked in?

Thanks again

854x4

Alright I checked my manual, and it shows

Cold -10 to 50 Celsius --------------- Hot 50 to 100 Celsius
G1 to G- 125 to 200 ohms --------------160 to 235 ohms
G2 to G- 125 to 200 ohms --------------160 to 235 ohms
NE to G- 155 to 200 ohms --------------190 to 290 ohms

You have
G1 to G- 309 ohms BAD
G2 to G- 154 ohms
NE to G- 312 ohms BAD
The reason you had to set your meter to the 2000 ohm scale is because the meter will only read up to 200 ohms on the 200 ohm scale. It looks like you have a bad distributor and need to replace that before going any further. The igniter might not let you do the (Tap Test) without having a good distributor plugged in. The distributor might fix the no spark problem or it might just get you one step closer but it is bad going by the numbers. Also yes that's why they call it back probing is because you need to back probe the wire while it is plugged in. Be careful back probing wire sometimes you will not get a good connection. Glad to see someone actually testing things instead of just throwing parts at it.

854x4

I just checked a distributor that I had laying around that came from a running 89 3vze, the measurements I get are
G1 to G- 339 ohms BAD
G2 to G- 169 ohms
NE to G- 341 ohms BAD
This distributor came from a supposedly running truck with a bad head gasket. I can confirm the blown head gasket (I'm rebuilding it)but I cant confirm that it was running but I have no reason to doubt the guy that sold it to me. I'm leaning more towards you having a possible bad igniter.

Capsulated

That is very interesting - thank you for that info. What I had been wondering is if the truck would still spark even with these readings. I am wondering because my truck was also running just fine until I pulled out the battery to replace this ground cable shown in the picture. Is it possible that I shorted something out when pulling the battery? I have read posts about bad grounds, to check wiring etc.. but I am in the process of educating myself about how to do this because there are procedures mentioned without the instructions. Going back to my test light not flickering when the engine is cranking while probing the ignition coil, I found a youtube video which the mechanic has this comment posted "No flicker = no control = cam or crank sensor issue, a bad igniter or module, a faulty computer, no power or ground to computer, or a shorted 5v reference circuit" -- I would like to check the "no power or ground to the computer" (is that the ECM located under the passenger kick panel?) It would be weeks before I could afford any new parts and I am happy to educate myself on proper diagnosis rather than just throw parts at it. Troubleshooting is in my nature because I have been a computer geek since the early 90's and have always wanted to learn more about working on cars.
Cheers

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I just remembered something. My truck used to throw a CEL after hitting a certain RPM while the truck was still working. The code was 11 if I interpreted it right.. CEL would not be on when I started the truck. I could drive and only until I hit that certain RPM, the CEL would not show. This website showing ODB1 trouble codes https://www.2carpros.com/articles/to...thod-1990-1995 says that "Code 11 Momentary interruption in power supply to ECU (electronic control unit or computer) up to 1991" - Could this be related to my current issue? Could you point me in the right direction to follow up with this?

854x4

It could be a bad computer power or ground I forgot about that. One test I use is does the check engine light light up when you turn the key on? This usually means the computer is getting some power and working but it doesn't hurt to check the power and grounds anyway. If the check engine light doesn't light up with the key on then you either have a bad bulb or the computer is not getting powered up. The computer should be located behind the passenger kick panel. to test the powers and grounds you need a wiring diagram and a test light or you could use a multimeter and check voltage drop but I like the test light. Test each wire (power and ground) with the other end of the light hooked to the battery (or at least a good ground or power) and crank the engine while testing each wire, this will load the circuit and you should be able to tell if you have a bad wire because the light will get real dim or go out. Going a little dim is ok because the starter is drawing current while cranking but the light should stay bright.

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I don't have a CEL when I turn the key on - which is odd because I would think that I should be getting one? When the truck was running, the Code 11 CEL would come on once I hit a certain RPM. Checking for ground and power to the ECM are what I want to check since it's something I can tackle without having to replace a part. I found this thread about testing the ECM https://www.yotatech.com/forums/f116...e-nuts-186678/ and it has a page from the FSM in there about checking it. However, I ended up taking some pictures and posting a new thread asking for some clarification because I'm not certain what wires I should be probing since I can't find a color-coding chart for me to cross-reference. I want to ensure I'm probing the right wires because I don't want to risk damaging anything. My post about the ECM is here at https://www.yotatech.com/forums/f116.../#post52338048