UKrunner

Can some one please take a few pictures of the vacuum lines connected the engine and the air intake tube? I can get the egine to run if I play with the throttle but if I take my foot off the accelerator it will eventually die. I did notice that as it's dieing as soon as the warning lights light up on the dash it fires right up again and runs fine for a few more seconds. It does this a couple of times until it finally dies completely.

hross14

did you check the plug wires?

The haynes manual i have states the firing order is 1-2-3-4-5-6.....but that is wrong!!!! Double check that and just to test the system--cap off all the vacumm lines to emissions and etc....

UKrunner

Plug leads are in the right order. Capped off all vacuum lines. Problem still exists.

It's interesting that as its dying, as soon as the warning lights flicker on the dash, it will jump back to life and then slow down, sputter and either jump back again when the dash lights come on or die if it doesnt "catch". IF I feather the throttle it will run all the time, smooth at first then rougher and rougher until randomly it clears up again and runs fine for a few more seconds.

hross14

I dont want to frustrate you--but that is exactly what my toyota did when i had the leads reversed.

Is it running really rich? Are the cats glowing? Crank and Cam sensor are clear from obstructions? No vacumm leaks with the intake manifold? Timing belt on correctly??

I know this sounds frustrating but it sounds a 180 degrees off. That is a saying we used here in the states when a distributor was 180 degrees off.

Is there another engine you can check to make sure the leads are correct. I, much like yourself did all the same things you are doing--then i checked my leads against a stock truck and wouldnt you know it--they were wrong.

Also, the lower intake manifold has air passages in it to inject air right at the injector spray nozzles--make sure all injectors are seated properly and the !!!!!!!!!THAT VACUMM LINE AT THE BACK OF THE INTAKE MANIFOLD--IT HAS TO BE HOOKED UP TO RUN!!!!

Had an AH HA moment--there is a vacumm line at the back of the lowest/lower intake manifold that feeds the air passages to the injectors. It is the "Y" kinda shaped one. In order to idle right I think it needs to be hooked up. Check that one out also--and verify with another running yota the lead order.

Good luck

UKrunner

Thanks for the follow up. This is West Michigan, I think there are 12 Toyota's here!!! Gonna be hard to check my leads with another engine so if anyone has pics that would be nice.

Whats this vacuum line you speak of? I dont see a Y shaped line. Any pics of this?

UKrunner

Triple checked plug wires and they are in the right order. 1-4, 2-5, 3-6.

UKrunner

Checked the timing marks. Both camshafts line up with the notches and the crank pulley is at the 0 degree mark.

hross14

I dont have a picture on hand--but it is under the middle intake manifold. You would be able to access it from the rear of the motor. This vacumm line leaks air directly to the injector tips where it helps atomize fuel.

Check it:


Air-assisted Injection

Prado's air-assisted fuel injection system improves fuel economy, reduces emissions and better stabilises idling speed. It improves fuel atomisation by combining an air stream with the fuel at the bi-directional injector tip. The air-assisted fuel injection system consists of an air bypass pipe from the main idle speed control valve (ISCV) to the main injector nozzles.

The 5VZ-FE engine's electronic control unit controls the air-assist system, using information from a pressure sensor in the intake manifold. The air-assisted injection system provides finer fuel misting. It also allows for fine-tuning of the intake manifold air volume when there is a large negative pressure in the manifold - such as when the engine is on over-run.

AND

http://www.mr2.com/files/mr2/techinf...a/3vzVS5vz.pdf ***PAGE 84***

I cant find an image but it is the hose that connects to the IAC valve (Not the two coolant lines) and goes to the back side of the motor. There will be a black plastic "Y" and then two more short formed hoses--on nipples coming out of the intake manifold. While you are back there you should also make sure your coolant temp switch is hooked up.

Give that a try and then we will go from there. Its just hard to figure out a problem when you are not there!!

UKrunner

I'm finding the hose from the IAC and following it as far as I can reach. When I tug on it it doesnt move but I cant see any connections down the back there and I cant see a y shaped fitting. I also cant see nipples on the manifold. And, I dont remember this from when I had the engine on the stand.

Anyone have good pics of the back of the block? There are some on here but I dont see what hross14 is talking about in those pics.


Could it be the IAC itself? Looks like I'd have to remove the upper intake manifold to get to it.

UKrunner

OK after some interesting stage lighting using LED's and a cellphone camera I managed to get pictures of all the joints and connections at the back of the engine, and it all looks correct. No cracks or splits visible, its routed correctly and I dont see any sepage.

So, timing belt and gears are good/ no teeth skipped
Plug leads are correct
Hoses are correct and not leaking
Fuel pump is running
Grounds are checked ok
No check engine light
Springs to life as the dash warning lights come on

2 things are going through my mind: IAC and electrical.

IAC, doesnt idle and this engine was a roll over - everything had oil on it or in it and has been sitting for possibly 2 years, so the IAC could be blocked. Can I clean this in acetone?
Electrical because as soon as those lights are on it picks right back up and runs smooth for a few seconds. So relay of some sort?

UKrunner

IAC clicks when power is applied to either of the pins and I can feel the air flow change when blowing or sucking through the tube. Should it go completely closed or is there always some air flow?

Also I discovered the PCV is open whether blowing or sucking. I dont think that is the issue but it cant hurt to have a working item in there.

hross14

the pvc needs to be cleaned. check your hoses and make sure they arent clogged either. I would use a can of electrical "stuffs" cleaner on the IAC.

Man oh man right computer??

UKrunner

Yes, correct computer, I got everything off the same vehicle.

I cleaned the IAC and bought a new PCV, regapped the plugs and it runs much smoother but still wont idle. I've drained the fuel tank and will be getting a new filter fitted on Monday. I twisted the end of the metallic line that goes into the filter and split it.

I still dont understand why it picks up when the dash lights come on. What the heck would change at that point? Is it not looking for a signal when its cranking vs when it'ssupposed to be running, and that signal is missing?

UKrunner

New fuel lines and filter fitted. Slightly better running - able to keep it alive long enough to put it into reverse and drive 4 car lengths. Still will not idle.

Out of ideas now unless the fact it has no airbox nor air filter, 2 feet of exhaust off the headers, no cat, no O2 sensors, no evap is stoping it from idling.

Fink

Great thread, you seem to be getting it reasoned out slowly but surely.

I'd be happy to rename the thread, just let me know what you want it titled.

Fink

RobD

Does it need the first O2 sensor to get an accurate reading of fuel/air ratio? Someone with better knowledge of O2 sensors should chime in.

UKrunner

I'll pm you with something witty when I've thought of it. Its a great thread for you guys, its record of despair and wifely anger for me!

See I thought it would have needed the first O2 also, but searching the site, there are poeple who have ran their engine just fine in the same condition as mine.

My dad tells me to get an exhaust on it and take it for a hard run to clear out any varnish or stuck residue of the intake and injectors.

Fink

You might try hitting it with a dose of Seafoam if you think it would run long enough.
You could also try some fuel injector cleaner, however, with it running as poorly as you say it is you may not see the benefit in time for it to even make a difference.

Fink

UKrunner

A bit of a development! I replaced the plus and it ran long enough for me to get out and play with things in the engine bay. This is the first time I've had the chance.

So, like other people, I put my hand over the maf and bam, idle picks up and it sits there purring like a kitty!!
So is this indicative of a massive air leak? Do I need the air box and filter on it to create some restriction in the intake? Should the arrow on the maf point towards the engine? Pic of the maf installed would be great if anyone has one.

GETTING CLOSER!!!!!!!

RobD

I don't think you need it covered. I have no airbox on mine, just a huge K&N conical filter and it runs fine.