are my fuel injectors bad on my 1994 j30t j30 infiniti?

Question

my car has 189,000 miles on it i replaced the spark plugs,pcv valve,and fuel filter...and the mechanic checked my car out and said one of my injectors is bad is this why my car idles so low it feels like it wants to die out at time? also one mechanic said there is a misfire somewhere? when my car is running and its in park it idles normally now when i put it in drive the idle drops and the car shakes but then if i turn the ac on the idle goes back up what do u think the problem can be?

Answer 1

When your car gets older your injectors are going to be staying open longer. This is due to carbon build up or dirty injectors. At 189k your car is doing a good job. When your engine is idleing you are going to feel the misfire much more then if you were going down the highway. Think about it this way. a foot ball is throw lighty, and spins, its off balance so it wobbles. But when you throw it harder and spin it more it is smooth and doesn't wobble. When you turn on your AC, your MAP sees a increase in load and turns up the RRM. The reason it see this is because it is driven by a belt on the front of the engine. When it starts up it slows down the engine a bit so there is a load on it. If it didn't up the RPM't then then there would be a chance of the engine dieing. The misfire is going to be from the injector. I hope this helps a bit.

Answer 2

Sounds to me that you may have a dirty idle control valve. Somewhere near your throttle body, there is a computer operated valve that controls the amount of air that is entering your engine at idle. It is normal for these valves to collect engine oil vapors over time, and require cleaning. In your engine compartment there is a tune-up decal that ordinarily will show you where this valve is located. While you're there, go to a do-it-yourself car wash and shampoo the entire engine bay. Also, find your PCV valve and clean it, as well (it also collect hot oil vapors). When you put your AC on, the computer automatically raises the idle speed (via the IAC valve) to accommodate the extra strain caused by the operation of the AC pump. If you think you have a clogged injector (not very likely) go to the auto parts store and buy some Chevron fuel system cleaner, using it according to directions. At this mileage, you should consider a thorough de-sludging treatment. If you want to know how, E-mail me!!! Good Luck!!!

Answer 3

The injectors in this car a JECS side feed multiport injector with the number 0G55 or 5G55 stamped on top under the aluminum retaining cap.
This type injector normally doesnt get clogged but rather fails to coil malfunction. Pull the plug connector off each injector. And touch an ohm meter to each of the prongs, it dont matter wich one is positive or negative. the ohm meter should steady out at 11.8-12.3 if your much higher or lower than this the coil in your injector is bad. this overloads the circut causing the injector not to fire which in turn causes a miss.
you can replace just one but you should replace all six injectors at once, this will elimate future injector problems.
check out this website www.fuelinjector.citymaker.com They sell these injectors for $39.99 each reconditioned. Compare that to about $160.00 for new

Answer 4

Infinity J30t