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Injectors stuck open!

'90 maxima 245,000 miles…over the course of a few days all three rear injectors (1,3,5) are stuck open and dumping fuel…lots of white smoke and fuel smell. Mechanic told me to replace the fuel injectors, that they are bad. I do not believe this since i recently replaced the injectors. I confirmed the Ohm on the injectors(10-14) and it is getting a spark…i heard that it could be the wiring harness is grounding out? how do i test this? could my ECU be bad? thanks.

Unless you are planning to be driving at Lamans, this is indeed a problem!

Injectors stuck open? That’s a weird one. And three stuck all at once? That is really weird. And it seems very unlikely. How was this confirmed? Did the mechanic pull all the injectors and test them side by side?

Unless you got a really bad tank of gas, or you recently changed the fuel filter – which can inject debris into the fuel line sometimes — I’m thinking it is an electronic problem. Either the engine control computer is on it’s last leg, or a loose or grounded connection somewhere.

It should be possible for a fuel-injection-trained mechanic to verify one way or another if the supposedly bad injectors are getting the right congtrol signal. That’s probably the first place to start. You’ll probably have to get an auto-electrical expert to help you too.

Are you absolutely sure the injectors are being held open constantly on the rear bank? White smoke is generally a sign of engine coolant entering the combustion chambers.

You should be able to listen to them with a stethoscope and verify if they’re clicking or not. If they’re clicking then they’re not staying open.

I do not have a schematic handy for this car but if the injectors are really being held open constantly I would tend to think this may be a fault with the ECU. It’s hard to imagine the leads between 3 injectors and the ECU all grounding at once due to a harness fault.

I had the same thought as OK4450. This sounds more to me like coolant is gettng drawn into the cylinders, more like a blown headgasket. Burning excess fuel makes black smoke, and if you were dumping fuel into the cylinders you’d flood out three and substantially reduce the spray from the other three. I doubt seriously if the engine would run with three injectors stuck wide open.

Has the engine been overheated recently?
How did the mechanic diagnose this as stuck injectors?

Check the dipstick.If the problem is dumping gas the oil level will over full and smell like gasoline. If it’s a head/head gasket problem the oil will be milky.

If the injectors are truly dumping gas, and they are all on the same bank of cylinders (assuming you have a transverse-mounted V6), I’d look for something common to all 3. I don’t know if the computer supplies “hot” or “ground” to fire the injectors on your car. You could have them all grounding when they shouldn’t, or you could have an internal computer problem with the circuits that ‘drive’ the injectors for that bank.

i thought it was the head gasket too, but yes, gasoline was pouring out of my tailpipe, the problem is the fuel isnt being burned…its raw fuel…i went to a different mechanic who said he thinks it is the ECU, not the wire harness grounding. He is putting it in tomorrow…i really hope it works!. Thanks for your comments.