brad11140

OK guys I need some feedback. I have a 1993 4Runner that I just got back from the shop. The engine is rebuilt and after a lot of time and troubleshooting we have it running pretty good.

So it idles well for about 2 minutes than dies. We pull the hose off the throttle body inlet and there is gas there. Further investigation reveals that the plastic 45 that connects the hose to the inlet housing is full of gas. FURTHER investigation reveals that the resonating chamber is completely full of gas.

Dump it all out. Reconnect and it fires right up. Idles for 2 min than the same thing.

I have checked some of the obvious. Did a resistance check of the cold start injector. Got 3.3 ohms. The FSM allots 2-4ohms, so I think that's good. I leave the connector to the cold start injector off and try again. Have the same result. Everything is full of gas. Common sense tells me that it has to be the cold start injector.

Could the cold start injector be leaking by. Even though resistance is good, could the valve be stuck open?

I tried jumpering the fuel pump and than looking into the plenum with a flashlight, but it was very difficult to see if fuel was flowing.

Appreciate the help.

thook

3vze or 22re?

iamsuperbleeder

dude it's in the thread title?

brad11140

it is the 3vze

thook

Pardon me.

iamsuperbleeder

OP

It does sound like the cold start injector to me as well.

Unfortunately though, I'm not a 3.oh guy

thook

Okay, I can see this post was confusing. Sorry. Happens sometimes when one is tired and posting hurriedly.....

Edited version:

Pull the cold start injector and plug the hole with a cork. It may be a little tough to start, but as warm as it is, not that bad. See if the injector continues to eject fuel after a few seconds. If it does, disconnect the electrical connector to see if that changes anything. If not, the injector's obviously leaking. If it does stop, it would mean the injector is continually getting ground to the time switch or the coolant sensor circuit.

Yeah, sorry about that. I'd been working on my brakes all day in the heat. Guess my brain's a little overheated.

iamsuperbleeder

isn't there constant fuel pressure in the line leading to the CSI? so if you just removed it, fuel is going to spray out of the line?

I suppose, if it's a banjo fitting like on the 22re, you could just use a nut and bolt, and reuse the copper washers, and block the end of the line off...

thook

Yeah, but I'm not recommending disconnecting the fuel line. Just pull the injector, with the line connected, from the plenum. Then,,plug the plenum with a cork.

The only other two considerations are the EVAP if full of fuel or lines misrouted, or the fuel pressure regulator has ruptured. Pull the vac lines from either and see if there's fuel in the line. I guess it would actually be easier to start troubleshooting this, first.

brad11140

OK, I just checked. The line going from the charcoal canister goes to the top port of the TVV. The bottom port is routed to the inlet of the throttle body. This is correct according to the FSM. As far as the fuel pressure regulator is concerned. How would that introduce fuel into the inlet, other than if over pressurizing it was causing it to blow by the CSI. I have good idle and combustion for probably 5 minutes, last time I tried.

thook

If the internal diaphragm of the regulator has ruptured, the vacuum will draw fuel into the intake. The vacuum at the intake is what opens the regulator and allows it to close. If you look, the regulator vacuum line routes around the front of the plenum, then underneath, then over to a switching valve on the pass side fender well, and then from there up to the plenum.

brad11140

Suppose it is a possibility. I wish there was a way to determine for sure that it is the problem.

I went and looked. You have the fuel pressure regulator. The vacuum line comes off the top of the regulator and connects to one of the small tubes which ends up running underneath the plenum and than is connected to one side of the VSV. The other side of the VSV connects to the plenum at that 3 port connection. So I would have fuel flowing through my VSV and into the plenum. Would make sense. There would be a vacuum at the 3 port connector, right? And if fuel was getting by the regulator it could conceivably be going backwards.

thook

I'll reply tommorrow. Time for bed, eh.

thook

Yes, there's vacuum at the three way port. Stronger vacuum at idle than open throttle. If there's a rupture in the diaphragm, the fuel will be drawn into the plenum. They way to tell for sure if that's the problem is if there's fuel in the vac line or atleast a strong fuel smell. There shouldn't be either.

brad11140

Ok. Back from camping. I purchased a replacement fpr. Before changing that out I decided to investigate a little further trying to find the source of the fuel. Found it. The line that hooks to the resonating chamber. It's a rubber hose that connects to the piping on the front of the engine. It goes under the plenum and comes out on the passenger side where all of the vacuum lines are. The connection splits in 2. One is connected to the idle up valve where the vsv,s are. The other line disappears going toward the rear, to the gas tank I suppose. When I pulled the line off while running it was pouring fuel into thAt chamber. Not sure what s going on here

thook

Neither am I, I'm afraid. I'll have to have a look at my wife's 3vze, but if it's the line I'm thinking of, it's for the PAIR reed valve. Gimme until tomorrow to reply back.

BTW, can you get some pics of the area in question. I think you have some vac lines misrouted. Not sure, but sounds possible.

thook

Does this look about right?

http://personal.utulsa.edu/~nathan-b...78pulsedse.pdf

brad11140

Figured it out. The morons I paid to rebuild this motor had everything screwed up. When I got it back from them and found all of the vacuum lines plugged into the wrong places I should have known that they probably plugged other stuff in wrong. I was mistaking before. My resonator chamber was hooked up properly. It goes into the line that goes to the pair reed valve. The chamber I was referring to was the smaller chamber under the resonator that tees into the outlet side of the vafm. This chamber also has a rubber line that comes up and connects to one of the pipes running under the plenum. All of the fuel was coming from the fuel return line. The fuel pressure reg line also comes out on the passenger side and returns to the tank. These smart guys had the fuel return line plugged into the pipe going to that smaller chamber under the resonator. It was a teed line with the other line going to the idle up valve. The line off the other side of the idle up valve was plugged into the fuel return line. So now it runs great. Thanks for all of your input and hopefully if someone runs across the same problem they can find this thread.

thook

I'm sorry.......I gotta laugh....BAHAHAHAHA! Unbelievable!! Man! I knew something was screwed up royally. But, I usually go with the likely suspects first. I guess I just assume too much when someone reassembles a motor, they're more likely to do it atleast mostly correct. Wow! Thank you much for replying back with your finding. And, very good work, dude! Congrats!