My '95 Maxima vibrates when starting up and till driving to 30mph. From my research, one of the injector misfired. It has more than 230K miles so I decided to replace all three (inner ones) to save trouble in the future. Now the car misfired again. Is it possible that one or more of the older injectors is misfiring?

The mechanic charged me $635 on the 3 injectors and labor. I'm looking to buy the injectors (OEM Bosch) online for a cheaper price. Local nissan sells it at $120/piece. Courtesyparts.com has it but has two different price, one at $97.72 and another at 89.27 plus $2 for o-rings. Has anyone ever bought injectors from courtestparts and what is the stock part # for '95 Maxima?

Does anyone know any cheaper online sites?

 

how about taking your car to another mechanic to be sure is the injectors
it could be a lot of things or a combination like
fuel filter
air filter
bad plugs
fuel pump
ignition coils
pcv valve
idle air control valve
even a vacumm line leaking
do yourself a favor take it to another person but don't say what has been performed on your car let him find out and give you his diagnostic after that then decide or write again telling us the results

 

did u check the ecu yet for any codes

 

I have the exact same problem with my 95 maxima, diagnosed as 2 injectors misfiring. Are cylinders 3 and 5 on the same bank, out of curiosity?

 

Stop throwing parts at cars. Injectors are not known to go bad that often. people just assume they do. same with coils (unless you are a 99). The mechanic was probably happy as hell when he saw you coming. What makes you think the injectors are bad? how do you know its not a coil? or plugs? I get a discount at Nissan if you really need the parts. Usually works out to be the same +/- as courtesy without the wait.

 

The ECU indicate the injector was bad. The mechanic suggested to replace all 3 injectors on the same bank which I did even though only one was misfiring. As of now, I'm afraid the of the other older 3 is acting up.

 

What code did you get? As fas as i remmebr there is no code that says "injector malfunction" (I could be wrong). and yes cylinders 3 and 5 are on the same side of the motor. 3 = center closest to the firewall and 5 = far right closest to the firewall (both when looking at the motor from the front of the car.

 

Thats a fast reply. The mechanic told me he checked for the code and it indicate it was the injector, I wasnt there in person.

Mizzax, I PMed U. Check it

 

0603
0604
0605
0606
0607
0608

http://forums.maxima.org/showthread....31%3Cbr%20/%3E

 

yeah so that says cylinder misfire. says nothing about injector. that could be plugs, loosened deposits, coil packs etc. as stated previously, there is no code that specifies an injector failure. boy am i glad i work on my own car.

 

Why don't you check the stickies for the method of checking your injectors with a volt meter to see if there good? Thats what I did and sure enough one of my rears was faulty, so I spent the three hours taking the intake manifold off to get to the rear bank and then pulled and replaced the bad injector with one from Pepboys. It was something like $75. Done. No more problem.

 

Yeah, I got burned by one of my local mechanics for $1100. My 1995 car was misfiring and had poor acceleration. The mechanic diagnosed it as being two bad injectors. And he convinced me that it's better to replace all of the injectors at once. The car ran only slightly better...and only for a few months. Not too long after replacing the injectors, the engine light came on for the first time. It indicated a faulty knock sensor. My car ran great after replacing the knock sensor. But I often wonder if that's what caused the initial symptoms in the first place. This site is great by the way!!

 

hungurr, they recommend replacing all the injectors at once because there is a lot of work involved in getting the upper intake manifold off and that is required to get to the rear bank (3 injectors). You could have done all six yourself for $75 x 6 injectors + 3 hours. Also, I can't remember exactly, but I believe the knock sensor (code 0304) doesn't trip the CEL, if your sensor is bad then it just records the code, but doesn't display until you actually manually pull the codes from the computer, so if your CEL came on, then there must have been another code associated with it. Plus the knock sensor will just retard your timing slightly and cause you to loose a couple mpg. Hope this helps.

 

as mizzax said, there is no "bad injector" code. only misfire codes, which could be due to a number of things. coils and injectors are by far the most common cause. you can check your injectors by listening to them with a probe (s-scope, or put your ear to a screwdriver handle, rubber hose, etc). they will make a rapid "click-click-click" if they are working.

for coils, you can move them around and see if the misfire follows them. or ohm out the primary side to determine if the transistor is blown (secondary side could still be faulty, though). or you can take them out one at a time, with a plug installed, start engine and check for spark -- not 100% conclusive, but a quick test for the presence of spark.

secondary side coil failures (such as high voltage leakage) can be tough to diagnose. sometimes it's just a process of elimination -- if all else is good, replace the suspect coil(s).

but you have to read your codes first.

 

i got that error code from running cheap gas in my car

 

For Testing Purpose Only....Do at your own risk!!!!

1. Swap the two suspected coil with another coil.
2. If the misfired still exists on the same cylinder....then
3. Check the Fuel Injector resistance around 10ohm
4. If the misfired exists on a different cylinder....then
5. The coil may be the problem.

Misfired: Either the coil or the fuel injector....that is the first I should expect.

 

I have an idea on removing fuel injectors easy way.

 

To validate the "Many" things it could be when you get a misfire.......

I got the usual coilpack misfire. With the A/C on at traffic lights, it was really noticeable.

So I ordered a set of the NGK Platinum plugs because I couldn't remember the last time they were done. and when they arrived, changed them out. When I got to #3, it was in a pool of oil. Maximum Tuning did the valve cover gaskets less than a year before, so back it went to be redone!

Misfire went away. Eventually, that coil pack did go! I read up that NAPA has a great track record for working well and NOT kicking any codes. Not a peep out if it since!

 

Care to enlighten us Mr. Gravedigger?

 

Put a timing light on it and pull your codes...