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Fuel Injectors not firing! What would cause this?

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Old 08-10-2016 | 05:19 PM
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I think I'm down to hauling it to the dealership, everything checks out, and I have threw a lot of parts at it. this 4runner ran great before I changed the knock sensor, and now its just killing grass in my yard.
Old 08-10-2016 | 05:22 PM
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Originally Posted by nuknuk
I think I'm down to hauling it to the dealership, everything checks out, and I have threw a lot of parts at it. this 4runner ran great before I changed the knock sensor, and now its just killing grass in my yard.
Did you try the starter fluid in the intake? Will it fire up?
Old 08-10-2016 | 05:31 PM
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Originally Posted by Trents3.slow
Did you try the starter fluid in the intake? Will it fire up?
I have before and it did nothing. will try again
Old 08-10-2016 | 05:45 PM
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Originally Posted by nuknuk
I have before and it did nothing. will try again
Try it again and let us know.
Old 08-10-2016 | 09:12 PM
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Hmmm. If you have spark, fuel and air, it should (at least try to) start. But there is at least one case where it won't; if the distributor is 180° out. So if you can verify spark (put your timing light on each plug wire; if the timing light flashes the plug is firing) and verify fuel (a squirt of starting fluid counts) but it still won't fire, it could be your spark is at the wrong time.

First, use your timing light to check that timing is at least close. (you said timing is "good," but you've got the timing light connected so just take a look) Now you're going to have to take off the upper timing cover so you can see the cam sprocket. Turn the crank to TDC -- and turn it one more time if the sprocket mark is pointing down (there are two TDCs per 4-cycles). Now lift the distributor cap and verify that the rotor is pointing at the #1 plug wire (actually, about 10° past it, but you can't really tell that accurately. Just make sure it isn't pointing at #4)

Good luck!
Old 08-13-2016 | 05:57 PM
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Originally Posted by nuknuk
I think I'm down to hauling it to the dealership, everything checks out, and I have threw a lot of parts at it. this 4runner ran great before I changed the knock sensor, and now its just killing grass in my yard.
I hope we didn't loose you to a stealership. If it ran before you pulled it apart it can run now. What's the status?
Old 08-16-2016 | 02:14 PM
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Ok, so I finally got out and messed with it again. First I tried the starting fluid, with no results. I sprayed it where the cold start valve goes, I tried it at the throttle body also, and nothing. So then I checked the timing and went ahead and pulled the distributor and started all over with it. Rolled the engine over manually, put the notch on zero with number one piston at top dead center, and reinstalled the distributor. Still got nothing. So then with my timing light, I checked for fire on all wires including the coil wire. NOW HERE I DID FIND SOMETHING, I had fire on all wires, but only on the coil wire, and #2, and #6 wire, did I have a very fast flash of light on my timing gun. All of the other wires, I had a very slow flash on my timing gun. So, is this info helpful???
Old 08-16-2016 | 02:50 PM
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Originally Posted by nuknuk
..., put the notch on zero with number one piston at top dead center,..
You may have done this correctly, but you haven't described it that way.

There are TWO top dead centers in each 4-strokes; one at the top of the compression stroke (where the plug is SUPPOSED to fire), and another TDC at the top of the exhaust stroke. If you just set the engine on the mark with #1 at the top, you don't know where the cam is, so don't know if you're in the right place. Your plugs MIGHT be all firing at the top of the exhaust stroke, and that will do nothing.

You need to remove the upper timing cover so you can see where the cam is. The cam rotates at 1/2 the speed of the crank, so the cam could be 180° out (with the arrow pointing down, instead of up). Once the the crank is at TDC AND the cam arrow is pointing up, then check the rotor in the distributor. Pointing at #1? Or 180° away?

The coil wire should "fire" 6 times as fast as each plug wire. The engine is only cranking somewhere around 60rpm, so the coil wire will "fire" 3 times per second, and the plug wires once every 2 seconds. I'm not sure why you'd be getting some plugs firing "fast."
Old 08-16-2016 | 04:42 PM
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Originally Posted by scope103
You may have done this correctly, but you haven't described it that way.

There are TWO top dead centers in each 4-strokes; one at the top of the compression stroke (where the plug is SUPPOSED to fire), and another TDC at the top of the exhaust stroke. If you just set the engine on the mark with #1 at the top, you don't know where the cam is, so don't know if you're in the right place. Your plugs MIGHT be all firing at the top of the exhaust stroke, and that will do nothing.

You need to remove the upper timing cover so you can see where the cam is. The cam rotates at 1/2 the speed of the crank, so the cam could be 180° out (with the arrow pointing down, instead of up). Once the the crank is at TDC AND the cam arrow is pointing up, then check the rotor in the distributor. Pointing at #1? Or 180° away?

The coil wire should "fire" 6 times as fast as each plug wire. The engine is only cranking somewhere around 60rpm, so the coil wire will "fire" 3 times per second, and the plug wires once every 2 seconds. I'm not sure why you'd be getting some plugs firing "fast."
ok, well when I was turning the engine I was also watching the rotor. But I will check the cam also. Also I check the cold start valve again, and it still does not spray, unless you put power to it with a jumper wire from the battery.
Old 08-21-2016 | 05:51 AM
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so I went ahead and put on a new timing belt and reset the timing from the beginning. It did look like the timing was off, but now I have it all right, AND yes it made a difference. Now when I go to crank it, it at least sounds like it wants to start and will even chug a little after I let off of the key. So sounds like I'm getting closer but still can not get this thing to fire off and start. So now it just chugs and sputters while trying to crank it, but no busting off and starting.
Old 08-21-2016 | 06:11 AM
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Originally Posted by nuknuk
so I went ahead and put on a new timing belt and reset the timing from the beginning. It did look like the timing was off, but now I have it all right, AND yes it made a difference. Now when I go to crank it, it at least sounds like it wants to start and will even chug a little after I let off of the key. So sounds like I'm getting closer but still can not get this thing to fire off and start. So now it just chugs and sputters while trying to crank it, but no busting off and starting.
Last time I had the "chug" symptom was when I took my distributer out and didn't put it in right. It's kind of hard to get them right. Try pulling that distributer you just put in and retarding and advancing it a little. The rotor will want to spin a little because the gear on the bottom so you need to compensate for that. There is a correct way of doing it but I just kept tinkering with it until I got it right. Pull the cap when you do it and see what cylinder it's on and get it close to that mark when putting it back in. I'm pretty sure it needs to be retarded.
Old 08-21-2016 | 06:13 AM
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Originally Posted by Trents3.slow
Last time I had the "chug" symptom was when I took my distributer out and didn't put it in right. It's kind of hard to get them right. Try pulling that distributer you just put in and retarding and advancing it a little. The rotor will want to spin a little because the gear on the bottom so you need to compensate for that. There is a correct way of doing it but I just kept tinkering with it until I got it right. Pull the cap when you do it and see what cylinder it's on and get it close to that mark when putting it back in. I'm pretty sure it needs to be retarded.
do i need to do this at TDC?
Old 08-21-2016 | 06:50 AM
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Originally Posted by nuknuk
do i need to do this at TDC?
yea. Get the crank on the zero and set the distributer.
Old 08-21-2016 | 06:53 AM
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I need a pic of the rotor position at TDC
Old 08-21-2016 | 06:57 AM
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Originally Posted by nuknuk
I need a pic of the rotor position at TDC
Take the cap off the distributer and roll the crank to top dead center. Take a mental note of where the rotor is and pop the distributer up and twist it back or forward to advance and retard it. Stick it back in and see what you have.

It's the back yard way of doing it but it works.
Old 08-21-2016 | 07:43 AM
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when i line up all the marks on the distributor and install it at TDC to rotor does not point at #1 on the dis. cap. It is over to the right of it. like a 2oclock. And does nothing when I crank it over. So I dont know, Im just pissed off at this point. twisting it back and forth still cant get it to fire off. Going to replaces the plugs, check the cold start valve again, I still honestly dont think my injectors are firing at all.
Old 08-21-2016 | 08:29 AM
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Originally Posted by nuknuk
when i line up all the marks on the distributor and install it at TDC to rotor does not point at #1 on the dis. cap. It is over to the right of it. like a 2oclock. And does nothing when I crank it over. So I dont know, Im just pissed off at this point. twisting it back and forth still cant get it to fire off. Going to replaces the plugs, check the cold start valve again, I still honestly dont think my injectors are firing at all.
There is no point in replacing more parts. If it started to "chug" then the plugs are firing. Get the timing right and it should run. You just need to play with it. It's not easy.
Old 08-21-2016 | 10:04 AM
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Just to be clear, engine at top dead with all marks lining up on crank and cam gear pullies. Marks on distributor should line up with mark on gear and housing then when inserting mark on housing to mark on camshaft bearing retainer.




Old 08-21-2016 | 02:34 PM
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Originally Posted by Trents3.slow
... Try pulling that distributer you just put in and retarding and advancing it a little. ... There is a correct way of doing it but I just kept tinkering with it until I got it right....
"Distributor." Yeah, there is a correct way to install the distributor. http://web.archive.org/web/201212070...13distribu.pdf Note that Andy A's picture matches the manual. "Tinkering with it" is fine if you have nothing to do all day, for a couple days ...

Originally Posted by Trents3.slow
... It's the back yard way of doing it but it works.
No, not really. You can't set timing without a $20 timing light. Put your timing light on and look. If you really are off one tooth, the timing will be out by about 28°. If you're within 28° of 10° BTDC (with the jumper in), then don't remove the distributor. Just set it.

Originally Posted by Trents3.slow
...If it started to "chug" then the plugs are firing. Get the timing right and it should run. You just need to play with it. It's not easy.
Correct, but more importantly, if it "chugged" it's getting fuel, so I doubt injectors are your problem. But it IS easy; just use a timing light. Without a timing light, "playing with it" isn't just hard, it's impossible to set the timing correctly.

The reason you need to follow the manual is because the distributor has a helical gear, so it rotates as you slide it in. But Toyota has it knocked; just match the protrusion on the gear to the mark on the housing. You don't NEED to align the distributor to the bearing housing retainer, as that will change as you set the timing. But there is no reason NOT to, as that position is "most likely" the correct timing. (You still need to check it with a timing light. If someone says you can set timing "by ear," remember that is just synonymous with "you can blow a hole in a piston.")
Old 08-21-2016 | 04:08 PM
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ok, I got the thing running I reinstalled the distributor and got it to start, BUT I cant get it to idle, and have to keep giving gas to stay alive and to start it. Thus by not being able to get it to idle, not sure if I can check the timing? I do have a timing light. Also when I was taking the intakes off to replace the knock sensor I broke the EGR valve, so I went to a junk yard and got one to replace it. WELL, I had my wife start it and keep it running while I look over things, and noticed that the EGR Valve was smoking, then I placed my hand at the exhaust tip and the exhaust coming out was HOT! So this is where I am at now, how to check timing if cant get it to idle? Bad EGR? and if so, is that why it will not idle?


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