1jz filling cylinders with fuel??

[suprafanatic]

So today my 1jz swapped mk3 starts missing out real bad. I simply think it needs new spark plugs so I went and bought new plugs. Put the plugs in and the car wouldn't start, wouldnt even turn over. Pulled the plugs back out and there was gas sitting in the cylinders. There was even gas pouring out of my wastegate :aigo: ... The car has a Stinger ems stand alone. Would this be a problem with the ecu? or something wrong with the injectors? After we cleaned out the fuel we put the plugs back in and tried to start the car. It cranked for like 2 seconds then stopped turning over. Pulled the plugs again to find the cylinders full of gas. I'm lost on what to do to fix this problem. The ground for the injectors seems fine to me.

 

[SupraCorwin]

Since i find it hard to believe that all six injectors got stuck full open i'd say take a look at the ecu, maybe hook something up to it like a laptop so you can get charts and hard data.

Possibly the fpr stuck?

Not really my area of expertise just throwing out ideas.

 

[suprafanatic]

The fuel pressure regulator isn't stuck, I even tried turning down the fuel pressure to like 8lbs. Still flooded the motor... I don't have a laptop right now to hook up to the ecu. I read about the stock 1jz ecu's having issues with caps. Is it possible for that to happen to a Stinger ecu?

 

[mkiiichip]

. The ground for the injectors seems fine to me.

What do you mean? The computer is supposed to ground the injectors.

 

[suprafanatic]

I was told the ground was on the intake manifold??

 

[toyotanos]

The sensor ground is bolted to the intake manifold, but the injectors are grounded through the computer. 12v is fed through a resistor, then to the injectors. If you have a constant ground to the injectors there is a wiring issue with either the harness or the computer.

I've seen used engines come into the shop with locked up injectors, open and closed. I'd pull them (I know its not fun) and try to see if they are sealing after you've verified the wiring and computer are working properly.

 

[suprafanatic]

its got 440cc injectors in it, not the stock ones. And how can I find out if its got a ground problem?

 

[toyotanos]

Do you have a high-impedance (high resistance) test light or a noid light set? If not, go buy a test light that has a high resistance value (20-100ohms) and plug it into each injector's plug on the harness and turn the key on. The light should stay off until you crank the engine over. Then it should pulse as the engine turns. If it lights up at key-on, you have a wiring issue. If it goes really bright and doesn't pulse when cranking you might have an ECU problem.

The fact the cyls are filling with fuel makes me think they're stuck open, but you need to find out wether its a mechanical failure (bad injectors) or electrical (harness/computer)

 

[suprafanatic]

No I don't have a test light like that. Can you buy them at an auto parts store like auto zone? And then I connect the test light to the injector clip and then crank and see what it does? Just making sure I understand you correctly here. Can I do this with the fuel pump disconnected that way it stops filling my motor with gas? And I also have the spark plugs out too. I just find it wierd that this many injectors would be sticking open together.. seems like a wiring problem to me but I guess i'll have to try this and find out.

 

[toyotanos]

Yep, I'll try to find a pic of the light I use here at work. Its not common, but when fuel system parts are drained of fuel and not treated with mineral oil/etc they have a tendancy to get sticky in my expeience. Fuel pumps, injectors, etc.

Yes, I would disconnect the fuel pump so you don't hurt anything in the engine. I'd also change the oil since its obviously seen a lot of gas.

edit: pic of generic test light:

Just make sure its a high resistance test light. I find they respond a little better to pulsed circuits.




Also, I posted this in another thread, but I don't think you saw it.
-Nate, I have you to thank for what my supra is today. You're the only other person on youtube who listed their lipp boss turbo. Its a little different than yours, but pretty close imo. T-4 comp billet 67, built 7M, etc. <3

 

[suprafanatic]

Nope I didnt see that but your welcome lol And ya I wasted 40$ in oil cause after it happened the first time I drained and refilled the oil.. thinking the problem was fixed I tried to start the car again and it just filled back up with gas.. so i'll have to drain it again ugh... A friend of mine is trying to get a hold of a noid light for me while I go to work. Which end of that thing goes to the injector plug and whats the other end go to?

 

[toyotanos]

It uses both pins of the injector plug. Basically if the test light is on, that means the injector is injecting fuel, and if its off the injector shouldn't be injecting.

I see three likely outcomes

1- Normal electrical condition (indicates mechanical failure with injectors)
Key off, engine off = light off
Key on, engine off = light is off
Key start, engine turning = light pulses

2- Injector drive circuit shorted to ground
Key off, engine off = light off
Key on, engine off = light on steady
Key start, engine turning = light on steady

3- Faulty ECU signal/map problem
Key off, engine off = light off
Key on, engine off = light off
Key start, engine turning = light on steady

alternate possibility in that scenario could be:
Key on, engine off = Light on steady
Key start, engine turning = Light pulsing or off.

 

[suprafanatic]

So just an update. Im starting to think its an ignition problem. We unpluged the fuel pump so it would stop filling the cylinders with gas when the car is cranked over. put the spark plugs back in the car and then went to crank the car to see if it would fire up for a min before it ran out of gas because there was still some gas left in the lines. The car cranked over for about 30 seconds then slowly stopped cranking. It never fired up at all. Then I pulled the spark plugs back out and there was more gas sitting in the cylinders. If there was enough spark the car should have fire up,, at least to my understanding it should have. So would this either be bad gas, or an ignition problem?? We pulled the front coil and a plug out and grounded it to see if it was sparking outside of the car. I cranked the motor over and the first time it sparked really bright. After that it had an extremely weak looking spark every time. It was dark out and I could barely see it sparking. Im not sure how big of a spark it should have but I feel like it should have been sparking more than that.. So what should I check next, Coils, wires, or ignitor? Any ideas?

 

[suprafanatic]

Is there a way to test the coil packs or ignitor?

 

[suprafanatic]

Ok we used the test light and a volt meter. I plugged the test light into the injector plug and the light stayed off untill we turned the key to the ON position. The light stays on with the key in the ON position. Then when we crank the motor the light stays on but also pulses as it cranks over... SO what would be your verdict on this? bad ground or wiring?

 

[toyotanos]

You can do the resistance check on the coils, but that doesn't say whether its a stong coil, it just tells you if the coil has the capacity to operate theoretically. (if there's an open/short the coil won't work)

I also wouldn't worry about the spark so much, as the cylinders are still having fuel in them again. Gas in the cylinders can reduce your compression to the point it takes a long time to get the car running even when fueled correctly, too.
Pull the gas cap off to get rid of fuel system pressure and pull the plugs out. Crank the engine over a lot to flush as much fuel out as possible then add some oil into the cylinders to give them some lubrication and then do the injector pulse test.

From the sounds of it, I'm thinking more and more that you have injectors that are leaking/stuck open.

Edit: just saw the extra post. sounds like you need to check the wiring- the injectors are on when the engine isn't running, which is allowing fuel to dump into the cylinders. Bad. You want the injectors to be off until you hit the key.

 

[suprafanatic]

You guys wont believe what was causing the motor to flood so much... lol spent alot of money and time working on everything just to find out I needed a new vented GAS CAP!!! There was a really old gas cap on the car and it wasn't venting so it was building up so much pressure that the fuel couldn't return back to the tank and it was flooding everything out. Got a new gas cap, flushed oil, had to flush the intercooler cause it was full of gas too. car started up and so far running good.

 

[GN_Convert]

good find!

 

[toyotanos]

I am suspicious of the diagnosis- but if it works, then whoo!

 

[suprafanatic]

Drove the car a few times and pretty good distances and its running very well now. We figured out it was the gas cap because we started to take the intake manifold off and we disconnected the fuel return line and gas just came shooting out of it. Realizing that the tank was pushing gas out I ran back and took the gas cap off and it stopped shooting gas through the lines and ALOT of pressure rushed out of the fill hole. Put the car back together and had to add more gas, left the gas cap off for the time being and the car started right up like nothing was ever wrong with it. However, there is still a slight issue. I went and bought a new vented gas cap for the car. Started the car then put the new cap on and let the car run for a while sitting. Turned it off, then later went to start it again and it wouldn't start. Took the NEW gas cap off and the car started right up. Why is the pressure not getting out properly? Is the new gas cap to cheap to work right? When I removed the new gas cap there was pressure that came rushing out again. Its a $6 cap that they had for our cars at autozone...