Dripping Injector floods engine now won't idle.

Our 99 Nissan Maxima had a severe injector o-rings leak on two injectors on a 6 cylinder engine while idling for two minutes. There was also a bottle of engine flush put in the oil pan. It flooded the engine to the point of stalling the engine. It was so severe that it won't start. While cranking it will crank several revolutions before it simply hydrolocks. I notice raw fuel spitting from the tailpipe when it idles. The center exhaust pipe was a quarter filled with fuel. I took that apart and drain it. The oil pan was drained. Two new injectors were put in, making sure it doesn't leak. The catalytic converter was removed and air dried. With the catalytic converter on or off the car it still won't idle. It will idle for 15 seconds with no knocks or pings then stalls even if I press on the gas pedal. It will easily re-start immediately but stalls after 4 seconds. All the plugs had spark and all the fuel injectors squirt fine. No smoke is seen coming from the exhaust. What part of the car is affected by a flooding that won't let it idle?

Thanks

Reply to
Ned Sanders
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My sister has a 99 Max that does something similar to what you are describing lately. One thing you may want to try is holding the throttle on the floor before and during starting. It seems the computer has functions to similate the old starving or flooded fuel conditions from the old carburetor days. By holding the throttle full open, it goes into flood condition clear by turning off the injectors until the flooding is cleared or the engine starts. By pumping the throttle while starting, it enriches the mix for starting. Your problem may also be related to the O2 sensor(s) being badly contaminated. IIRC, you have 4 O2 sensors.

Another possibility is the fuel pump if the stall is always at 4 seconds as this is close to the timeout for the fuel pump to stop if the computer does not sense the engine is turning. This is sensed through the ignition control circuits.

You may also want to use a nonresidue electrical cleaner to clean the MAF sensor just in case it has become contaminated with crankcase vapors or whatever else my pass through the air intake. There are pics on the net on how to do this.

In any case, I would suggest removing the negative battery cable for 10-20 minutes to allow the computer to lose it's rmemebered paramaters and stored fault codes. Reconnect the battery. Turn off all accessories like radio and air. Try starting the car by only using the ignition switch. Do not touch the throttle. If it starts, allow it to warm up for a few minutes if it will. Before driving, move the trans selector into eact position for a few seconds to allow the engine to relearn it's idle speeds. If all seems well, drive the vehicle around a few miles to allow the computer to relearn it's operating parameters.

If none of this works, you will probably need to have it checked by someone with the correct scan tools for this vehicle to find the culprit. I do not recommend the shotgun approach to auto repair by wholesale replacement of perfectly good parts.

Lugnut

Reply to
lugnut

You did put in new plugs to replace the fouled ones, right? Or if you're as cheap as I am, cleaned the old ones.

--scott

Reply to
Scott Dorsey

Don't know this car, but to answer your last question, a leaking fuel pressure regulator diaphragm can cause flooding. Only way fuel can go around the injectors as far as I know. Might be better to take it to a pro and get it on a diagnostic machine instead of taking it apart and putting it together again.

--Vic

Reply to
Vic Smith

"Ned Sanders" wrote in news:SzyCn.52841$ snipped-for-privacy@newsfe01.iad:

Did you replace the transmission fluid? You clearly should have.

Reply to
chuckcar

FIXED UPDATE: Thanks for your response. They really help a lot. Turns out the fuel on the O2 sensors probably dried up the next day or so (I think) that's what happen.. Now it idles fine To be honest, I was absolutely stumped when it refuse to idle even when I give it gas. It was a though a beast's breath was choked when it stalled. This prompted me to ask the universe for help because I really can't afford four O2 sensors, or better yet don't have the energy to replace these rusted-in parts. I really believe in this new age thingy. Well, it paid off.

How this ordeal began. If you want to avoid my mistake, please keep reading. Initially, one of the injector didn't fire right. I took three injectors out upon which two slip and fell into the ground. Upon falling into the pavement a plastic piece on the tip of the injectors cracked in half. Half asleep and not very bright I put new orings on them then lube them with some white lithium grease. And then put these broken injector back into the injector rails. I went to start the engine and two minute later the motor stalled. This is when the tail pipe is half flooded with raw fuel. The two new injectors I bought had these plastic pieces, but they look like unbreakable plastics. Honda fuel injector uses steel in place of these plastic pieces. Honda design there injectors so they cannot flood the cylinder chamber no matter how half asleep people are. I am sticking with a 96+ Civic in the future because it's easier and quicker to fix. This ordeal is embarrassing to mention but what is more embarrassing is that the designers can change this design. If they don't change it in future models, even a brand new injector can flood when the o-ring binds.

I am linking fuel injector images that are not mine if you want to see the difference.

Honda injector rail (notice that you can't really flood the cylinders.)

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Nissan injector (notice the grey, I believe, are now, unbreakable plastic)
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Reply to
Ned Sanders

Why?

Reply to
IGot2P

He should have checked the trans fluid, brake fluid, radiator fluid, rear end fluid, and windshield wiper fluid. Hey, you never know. :-)

Reply to
willshak

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