eddieleephd

can you check while cranking?

and all of this started with a tune up right??

and have you checked for fuel pressure?

what year is it?

SublimeBoa

Also about the ground, I checked continuity from the ground cable on the bat to several parts of the engine and firewall, checked it to the igniter body and other ground points in the vicinity. All is good. I have no rust, no corrosion and barely even any dirt anywhere in the engine compartment. Just bought new cables and new Optima 6 months ago.

SublimeBoa

I'll need to round up some help for that or install a remote starter switch, but yeah, I'm sure I could. Think it would make a difference?

SublimeBoa

Yeah, a simple plug change no less.

I have fuel pressure at the rail. That was the easiest and first thing that came to mind. I relieved the pressure, cranked it a couple turns, and checked it again. It had pressure. Since I filled my tank the night before, I was dreading that thought.

SublimeBoa

See, I know what the problem really is. I made a New Years resolution that nothing was going to boil my Irish blood this year.

So naturally, every day this year, something has tried.

eddieleephd

if there is supposed to be intermittent continuity with the black wire and ground possibly. have you disconnected the battery and cleared the ecm memory?
and did you check the signal from the ecm to the igniter?

I do not see what you do so what are the colors of each wire IGT,IGF,Ground?
was assuming black was ground but ???

and year

SublimeBoa

95, added it to my sig line.
Did disconnect battery earlier on after fuel pressure test to attempt to reset the memory, with no change in symptoms. Haven't tried since. Also have not checked between ECM and igniter.

I'll have to physically look when I have some light, but the FSM diagram says IGT is B/L and IGF is B/Y. Black goes to Tach and IG- and shows the body of the igniter as ground.

eddieleephd

Ok check the signal from the ecm before thinking it is the igniter because the ecm tells the igniter what to do and if there is no signal there then you will have to run different diagnostics to see why.

this should be your next step from what I see.

the ecm tells the igniter to fire it then tells the coil to fire.

SublimeBoa

OK, Thanks a bunch. Reading up on Timing belt change right now, just in case. I printed out the VAF, ECM and full ignition diagrams, so that's gonna help a bunch too.

eddieleephd

ok so the black wire should give a voltage when it is being cranked and then this may be considered grounded but it should be probably an ac voltage and this does not tell me at all that the igniter is bad more tests are required to diagnose...good luck keep us informed and We will be happy to assist.

SublimeBoa

Got a friend coming to help me with the things I need extra hands for this weekend. Went out yesterday to check the connection from the ECM to the igniter and never could get to the ECM. At some point an aftermarket alarm was installed, and the under dash area is just chock full of all the extra wire, sensors and misc crap that came with it. Tied up in there with about a billion zip ties makes it really secure, but really difficult to get it out of the way too. I ran out of light and patience.

Hopefully I'll get it all out of the way when I have more time to mess with it this weekend and get that test done too.

I did pull off the VAF and test the resistence on it since it was mentioned as a possible cause for no start, and I need extra hands to continue the other stuff anyway. It's way out of the ranges provided as correct. About 115 ohms low on the closed and about 200 ohms low on fully opened. Supposed to be 200-600 ohms. FSM says replace it. Not sure if that would cause my problem, but I don't like it being that far out of range. Could explain some other minor symptoms I was experiencing before the big quit.

Did notice a sticker on the cross member that says the timing belt was replaced 25,000 miles ago. Not likely that broke already, but not ruled out either. I would love to not have to take that all apart.

So, I'm at a stand still till I get extra hands involved to complete the tests.

Thanks again for all the help.

eddieleephd

you can bypass accessing the ECM by using some straight pins and pushing them in to the connector from the ECM to the Igniter parallel to the wire aka along side till they make contact and test for current that way. This is the easy way so there ya go if how ever you need to run more tests then you will need to access it for instance if there is no power at the igniter from ECM you should check at the ecm to be sure that there is not a simple short before diagnosing it as the ECM.
Also read up on the things that the ECM is looking for before sending current to the igniter and test those next if there is no signal to the igniter from the ECM any where.. I had a similar issue with my truck after replacing the engine and it turned out to be a short between the cam shaft sensor and the ECM causing the issue I went round and round banging my head on the fender before I figured it out. so there may be a short between the three coils at the distributor and where they go or they may be disconnected so do not forget to check those as well continuity test may reveal this but voltage check most likely AC I keep saying this because if you test it on DC and it goes + - + - + - + - you are most likely reading an ac current however if you test only with AC and it doesn't read any thing then test on DC before deciding it is not right or always test on DC and realize if you find this fluctuation to test on AC...

SublimeBoa

Geez, yer kidding me. A cam sensor? I thought a cams job was to spin and open valves at the right time and duration. Silly me.

Yep, gonna have to get serious about that refresher course. I've always been a decent mechanic, but I also always owned and worked on older vehicles. This newer stuff is kicking my butt with all the extra doodads, sensors and brains that can go wrong. And my truck is 15 yrs old. Now I'm scared to look into a new one.

Anyway, I'll try what you said about the push pins and see what happens once the rain lets up. Meanwhile, off to read some more FSM.

Thanks again!

eddieleephd

the cam sensor on my truck is on the front of the left cam and its basic function is to tell the ECM that the engine is at TDC, the crank sensor is at the front of the crank and tells the engine when each cyl is at the top from this the ECM knows when to tell the Igniter when to fire. since there are 3 coils to fire 6 cyl.s the igniter when to fire 1,2,or3. when the ECM finds where TDC is then it knows which coil to fire first second and third. I am kinda assuming that yours is figured by the three pick up coils and TDC does not matter because there is only one coil and the distributor rotates probably twice per rotation of the engine thus the fire timing. I understand where you are on these new engines I used to drive a 75 Nova and it had an HEI ignition which was high tech from the points that that my dads truck I learned on had. I am thinking that there is a simple fix for your truck some how I mean a simple tune up should not be this frustrating. pull plugs and replace what can go wrong especially one at a time. is probably some thing that you are over looking like a loose coil wire to the distributor. as a matter of fact do you use di-electric grease??? this can be a simple fix. My friend last year had an issue where he parked his truck and when he went to start it no go!! I fixed it by pulling the coil and cleaning the chassis grounds applying a slight bit of di-electric and doing the same with the wires to the coil and as well all of the wires to the plugs pull clean di-electric. put it all back together and vroom no more issues. Before then it was an intermittent issue and he just could not figure it out so if you did not use di-electric then I would suggest trying this before going any farther with diagnostics. I tell many people to do this.
At one time I couldn't stand the stuff because it seemed like some useless funky stuff on electrical components until it fixed my misfire issue a couple of years ago on this truck. so yeah there is a little learning curve but really not that great. What you need to do is look through that FSM and see what creates spark aka what the ECM looks at to send spark to the plugs then clean and test all of these components if that that doesn't work look at the ECM diagnosis chart and follow it for the ignition components one by one from the most likely to the least.

I wish you the best of luck,
ED

SublimeBoa

So I got it rolling again, just wanted to let y'all know that it turned out to be the Volume Air Flow Meter.

Friend that was supposed to come and help me out...turns out he has a 94 that he rolled in 2001, and has been resting under a tarp behind his shop since then. He says he plans to make an off road toy out of it some day, so wouldn't sell it to me for parts. Had to try though. LOL

Anyway, went and snatched the VAF the ECM the igniter and coil from that truck and come do a quick swap on my truck. He thought that'd be easiest, even though he might damage a good part from his truck. So we started with the VAF and it started first crank. Put the old one back on, no start. Going to get one from the junk yard tomorrow so I can give his back.

I'm stoked, but who woulda guessed?

Thanks for all the help! Some good info in here.
Rick

eddieleephd

Congratulations!!!
And Congratulations for having a friend that has this resource at his disposal

Yeah that is actually one of the reasons that I was saying to look at all of the things that the ECM looks at before replacing parts sorry I didn"t mention the MAF or VAF as possible suspects. Oh so sorry should have knoen to mention that.

the ECM uses the reading from the MAF/VAF to see how much was coming in by, then it tells the injectors to inject so much fuel, and the O2 sensors actually give it the understanding of how much air there is per cubic foot and the ECM uses this for fuel trim modification to get the 14.45% Fuel Air Ratio. so if there is no or inadequate initial volume/mass intake reading then there will be no initial input of fuel, and if there is no input of fuel the ECM will not give a spark to ignite. This is why I asked if you checked fuel pressure.
should have gone straight to air.

You can test the output of the air meter vaf/maf using the previously mentioned straight pin method for proper voltage. This process should be listed some where in the FSM you downloaded.

A good Friend to be able to save you the expense of that lesson.

This is part of the reason so many clean their vaf/maf regularly it will also assist in fuel mileage.

SublimeBoa

The VAF is one of the things that gave an inadequate reading when tested. It was actually the last thing I tested though. Someone mentioned it, I think in this thread, which is why I tested it. The FSM gives you the proper resistance it should be reading both closed and open and says if it's off, to replace it.




As soon as I tested the resistance on my friends, I knew that was going to be the problem. His hit right within the ranges provided. I'm just glad to be rolling again. Now to talk him out of that 94 Runner. Sure would be nice having a whole parts house just sitting on stand by. LOL

Now I can read that manual on my own time, instead of feeling pressed for time to find the problem.

Anyway, thanks again for all the help. Hopefully my problem will help someone out.

REALGRAVEROBBER

Never hurts to:

1.) Remove your battery-ground and (1.) Emry-cloth the contact points between the wire, chassis, and under the head of the bolt, then smear on a little electrical grease to prevent further corrosion, and reinstall. The negative battery cable, engine ground, and engine-to-firewall ground are all important!

2.) Add an extra battery-ground strap, going from the battery to the chassis.

3.) Remove and clean each end of the postive battery cable.

Usually after doing this, the (1.) engine cranks faster & starts faster, (2.) headlights are brighter, and (3.) entire system just seems to have some more zip to it.

I buy and sell a lot of cars in my spare time, and this is always done after I check the oil for the first time. Some cars that would NOT even start before, will start after getting sufficient Amperes to the starter.

Getting a new-to-you car:
1.) Check oil.
2.) Clean electrical stuff mentioned above.
3.) Clean under battery, battery itself, and battery area with baking-soda and water.
4.) etc...

clocklaw

subscribing to this thread so I can read it at home later tonight. Anyone have a thought about aftermarket coil and igniters?

clocklaw

Ok...so I ran through all of the tests and everything checks....does that mean the ignitor is bad?