wmayota

I'm not much of a mechanic, but when I was going through all my troubles, a guy at my uncle's garage said to check the little switch inside of the air box lid. That can get stuck sometimes and cause the engine to stall. I have no idea if that will help, but it is just something that came into my mind.

ChefYota4x4

iTrader: (5)

Not a 3.0 guy, so I'll not be of much use with this diagnosis. However, that basic FUEL-AIR-COMPRESSION-COMBUSTION standard is a good place to start. However-2, lol..... This sounds SO MUCH like an issue a buddy of mine had. He had some bad wiring in the harness, and every time he pulled upward on the main part of the loom, the thing would start.... he'd let go, and NADA! Also, it SEEMED to have spark, etc..... BUT, when trying to start it, turning it over, it was not allowing the plugs wires to get spark, most of the time. He tore into the harness, and low and behold, 3 corroded connections that made contact when pulled on but not when just hanging there.

Since you're not getting ignition when ether is injected...... I would guess either NO spark(hold the plug wire right to the block, with the plug in it, in darker conditions and check for GOOD BLUE SPARK).... orrrrr, the dizzy is way off. Even then, I'd assume you'd get SOME 'chuggachugga' attempts to start from it, ya know?

PICK UP COIL, 3.0'guys?

Dang, I'm interested..... Watching, best wishes,

Mark

fusion1620

Spark is good.. Timing is good.. Compression is good.. EFI?? No fuel with intake hooked up.. Something...
I'll let you know..

ChefYota4x4

iTrader: (5)

Maybe whatever the 3.0 uses as a "fuel cut" is defective? I've heard of the sensor that cuts the fuel to the injectors when you brake over 1000rpm going south and causing the fuel to stay off.

Rob2tech, whom I was helping for a bit with his motor, wound up with wiring in the harness being the main issue impeding fuel to the injectors.

Hope you get her sussed up soon!

Mark

VileKyle

By intake, i assume you mean air intake? Try cleaning/replacing air filter?

TNRabbit

If it fired up with the intake off but then doesn't when it's on I'm guessing you have a short in your wiring harness.

WesinTX

I would have say you are not getting air through the filter box and intake tube.

ChefYota4x4

iTrader: (5)

I believe what he said was "These guys removed the INTAKE to get to the INJECTORS, ....fiddled around and voila, it started". I would agree, as I hinted before, it would more likely be a harness issue or intake ground.... Something causing fuel cut to engage? Still, it's VERY strange, if you're getting spark all the time, that Ether wouldn't give you even a 'sputter' of ignition...>??? Could you clear up exactly what these guys did please? Maybe ask them?

No codes....that stinks... been there.

It started with the intake removed????? I'm guessing that it was still wired up and the AFM(MAF?) was still connected??

fusion1620

When we unhook the EGR pipe from the exhaust it tries to start.. We unbolted the intake manifold on the top of the motor. Put a piece of wood to wedge the intake off of the intake manifold and it starts up. Still trying to figure it out...

fusion1620

When we take off the air intake chamber, the truck starts right up. Put the chamber back on and it dies out......... Any ideas?

fusion1620

My latest idea is that the computer is not adjusting the air/ fuel mixture properly. I think there is a problem in the EFI system.. Possible?

ChefYota4x4

iTrader: (5)

Plenty of tests in the FSM and even more generic books for verifying/eliminating the EFI system(ECU, Air Meter, TPS, Coolant Temp Sensor, Injectors) and ignition related portions of whatever P.O.E. you want to lay out and attack.

As I said, not a Guru of any kind, let alone with the 3.0.... and yet, I find it odd that you're removing the Air Flow Meter from the picture(that is what you're saying, right? You're disconnecting the air tube from the meter and letting the intake just suck air straight in?) and it's running fine? Seems to me your springs/coils inside the Air Meter MAY BE shot? Obviously you still have to have it plugged in to run, but if it's not opening when you turn over the key, it apparently can not get enough of the one of major 3... "AIR". No air, no combustion. You said you've tried another Air Flow meter, right? (sorry if it's MAF on this model... as I said, not well versed on it, lol).

I tested mine with the normal tests, and then the FSM had more, telling me to open the plate with the IDL-E2 connected.... as I'm opening it, if it goes above 1K Ohms, radically, I would have an issue with the unit. That thing is VERY touchy..... but it must be opening enough to engage the fuel pump while turning it over, even if it's not connected to the throttle body, get me?(again, I'm guessing on this motor...but I would assume it's the same, guys, right?>>>Flap has to open to engage the Fuel Pump???)

fusion1620

The fuel pump engages while cranking, then the flapper takes over once the truck is running from what I have read... The fuel pump does come on when we press on our flapper.... It sounds like the truck is choking to death when we start the truck with the intake chamber off, then put it on and hold in down.. The mass air flow sensor in the intake tube has been swapped with a known good one. Also the coil, igniter, and the distributor, have been replaced. Knock sensor, distributor cap, rotor, and spark plugs have also been changed. The fuel pressure regulator has been changed. And the whole intake chamber was swapped with another on.. The fuel tank has been dropped and cleaned out. Fuel filter has been replaced..

It sounds like the truck is not getting enough air with the air chamber on.. Even with the throttle plate wide open and the air intake unhooked from the throttle body.. My guess it that it is either getting too much or not enough fuel with the chamber on causing the truck to die out. Fuel pressure problem, or the computer itself. We are going to try another computer today... Thanks for you help. Any tests that you can think to try, let me know..

ChefYota4x4

iTrader: (5)

If you go through my thread, you'll see the HUNDREDS of tests I ran, lol. (Troubleshooting thread, with TONS of input from others.) Far as the 'guess' I'd make?....I really don't like to do that, as it can lead to people digging in and tearing things up or throwing parts at it that might not be necessary... BUT, if you have lots of spares to try, HEY! lol.

ECU might be the issue.... BUT, since it seems to run with the AFM taken out of the picture, I would still lean toward Harness/wiring issue. OR, something with the "FUEL CUT" system has gone totally haywire.

NICE TRUCK btw! Seriously! Just hang in there, man, and keep digging... but if I may suggest: Make a clear and numbered Process of Elimination P.O.E.

Might wanna do that, starting now, on this thread....

1. Swapped out a., b., c., no avail
2. When intake tube is pulled away from AFM, intake pried up, it starts,
3. etc.,
4. etc........

Know what I mean? I know it's anal, but it's REALLY effective in bringing more voices to the 'theory festival'.... I would know, hahaha.

bunnone31

i just had the same problem with my 4runner? try replacing the mas air flow sensor thats what was wrong with mine

fusion1620

Just can not figure this one out!

Took the injector rail out toady..

Put it all back together outside of the engine and checked the fuel injectors.. All of the injectors are firing.

The cold start has more of a mist than the other six though.

Put it back together. Bolted the air intake chamber on, and she started up. Tried it like three times. Started up every time.

Took the air intake chamber off. Checked the injector wiring for shorts and wrapped it up good with electrical tape.

Put on a new upper intake gasket, put the air chamber back on, and hooked every thing back up.

Now it doesn't start again.

Tried a different computer.

Same thing.

The only thing that I have not checked is fuel pressure cause I don't have a gauge.

The friend is ready to tow it to a shop and pay an arm and a leg.

I am bummed...

ChefYota4x4

iTrader: (5)

Really sounds like; "When it's all buttoned up, for some reason it WILL NOT allow spark.

Just for the heck of it, turn it over with it all connected, one plug out, in wire, laid against the BLOCK or steering bracket. If you get spark, just for the heck of it, disconnect the #1 Plug wire from the plug and put the plug back in, just hand tight. Turn it over a few times(10 seconds) and then pull that plug out QUICKLY and see if it's soaked with GAS, k?

I think there are a couple things that could stop fuel from getting out of the injector. One is no spark...obviously you have spark WHEN it's firing up. However, for some reason, when everything is hooked back up, ....NADA! Is it possible that an igniter section of wiring is grounding out when you're buttoning it all back up and therefore, taking the spark out of the picture?

This is mind numbing, ...I can relate to him, THAT'S NUTS! Still, it really seems like either it's not getting air when things are snugged up, or it's not getting spark when things are snugged up,....or it's not getting fuel due to something cutting it off.

I thought you said you had an FSM...if that's the case, see if you can hunt down the "Fuel Cut" system. These things are OLD compared to many on the road, ...and yes, they're REALLY long living and reliable... but stuff like this happens, period.

Just a weird scenario for ya;

Buddy of mine had an issue with his fuel cut. Fuel cut engages when you hit the brake and the RPM's are over 1000..>Literally, CUTS OFF the injectors momentarily. This is more crucial in Auto's, so that when you are stopping, if you're pushing 1200rpm, there will be no fuel to push you through the stop light, lol. It is, however, in manuals, too(5spd.). For some reason, on my buddy's truck, the button that is pressed when the brake pedal is depressed, stayed pushed in. So, every time he tried to take off, it would just bog out, .....back up, then bog out again. Took him a while to track that down, but it's just an example of how some freaky stuff can go wrong. Tell him not to feel bad if he ends up entrusting a professional to figure it out. Just a hint....Toyota will usually check out sweet older trucks for free, to a point. If you have to pay, it's usually 98$ for a diagnosis. Just go in and speak with them as 'eager learners', and explain everything you've tried, and you might just get lucky and get a guy like many of us, "I HAVE TO FIGURE THIS OUT!" type guy, hahaha.

Best wishes, and let me know what happens with what I said to try, k?

davesluggo

I have found so many of these issues on here but never find the final outcome. I am having same issue. Can not locate the issue. Has anyone ever figured out the cause of this?

fusion1620

Well I'll tell you what happened. My friend ended up buying another motor from a totaled truck with low miles and it now runs great!!

When they were taking out the old motor he found the problem..

The truck had a one piece dual exhaust system.. The catalytic had a very bad rattle in it.. He cut the pipe and hollowed out the cat. When he clamped it back together, he thought it would be a good idea to use two pieces of cardboard with holes gut cut out as gaskets.

He forgot to cut a hole in on of the two pieces therefore blocking the exhaust flow..

rustyf99

iTrader: (1)

Ouch! I wonder how many simple mistakes have turned into big problems?