well i re did the compression test correct this time..as the key turned the compression would shoot up to like 150 on each cyl and as the car kept trying to crank compression would go up up up

i got these as results..
cyl 1) 200
cyl 2) 190
cyl 3) 190
cyl 4) 195
cyl 5) 190
cyl 6) 200


coils are all fine, but has a nasty misfire on cyl 5, once it start i have to rev it up quickly for about 2 seconds then its fine idles at 1,000rpms until it warms up then it drop to like 350 400 and runs like a subaru.. injectors seem to all be working.

 

How did you check the coils? Ohming them out? Same with the injectors?

 

That idle is too low for one ... compression #'s seem ok, did you change the plugs to try and correct the misfire? What codes are you pulling?

 

Move the coil from cylinder #5 over to 3 or 1 and see if the misfire moves to those cylinders. Might want to try the same for the injector if the misfire doesnt move with the coil.

Did you check the resistance on the injector?
Have you checked your plugs?

 

yes checked plugs. there all ok and only have like 300miles on them...swapped coils never has the misfire left cyl 5

 

Sounds like its time to swap injectors. Have you checked the resistance on the # 5 injector? I'd probably put the #5 injector on another cylinder and see what happens. It looks like you've eliminated any other causes...

 

isnt the cyl 5 injector under the intake manifold tho? i got an ohm tester and have no idea how to use it =) but yeah...

 

 

Take intakemanifold off its not hard

 

yayyyyyy... this is going to be fun!!

 

You can ohm it out through the subharness without removing the UIM. Just ohm all three so you can look for a difference, not necessarily an absolute value.

 

yeah ill have to figure out how to use my ohm meter and find the sub harness.. <-im an idiot haha

 

Check the coil boot and check that injector out. most likely it is the boot, ive never really heard of an injector failling on a max.

 

However, the o-rings quite frequently fail, causing the cylinder to either flood, or the fuel to leak out, causing the misfire, even though the injector tests fine with the ohm meter.

Also could be the insulator on the fuel rail. After 170K I had to replace several, as they had developed cracks and led to multiple cylinder misfires.

 

whats the insulator on the fuel rail? and i will check the O rings

 

There are six insulators, one for each injector. They are about the size of a quarter and sit over each of the nozzles on the fuel rail and provide the seal going into the lower intake. Since you'll have to take the upper intake off to get to #5 anyway, you might as well pull the fuel rail and check them. If you need new ones, go to the dealer. I paid about $5 for a set of six. Some autoparts stores have them but in my experience they're the wrong size.

When pulling and installing the injectors to check the o-rings, DO NOT TWIST. I learned this the hard way. The way the lower intake is machined, it will cut the o-ring all to hell.


Yeah, right. PITA, IMHO. The first time is the worst. After that, you get the hang of all the vacuum lines and whatnot. Have never done the job without a complete set of bloody knuckles. And thats the kicker. If it is just an o-ring or insulator, you lookin' at like less than a buck to fix it, but its labor intensive.

 

Just wanted to point out that you might not be so quick to overlook injectors...actually they fail quite often.
hope that helps.

 

you guys are great! and i appreciate all the help and important info you all have given me. i just need to find someone who has done this before and has patience!

 

anyone know how to hook up the "actron cp7672" ? it has 3 slots for the positive and negitive wires. im guessing the black wire goes to the last hole? and the red one goes to the V(ohm symbol)mA slot? never used one before!

 

I had 2 bad injectors on the engine I swapped into my Max (they still clicked but I guess weren't spraying right, o-rings looked fine). One was easy to reach but one was under the UIM.

 

If you're referring to a digital multimeter, red goes in the one labeled V, Ohms, mA. Black goes in the COM slot, most likely the one near the bottom. If it's auto ranging just set it to measure resistance (ohms) otherwise set it to resistance with the correct range.

 

thanks!!!

 

injectors are a common problem on the 4th gens with 100k+ miles. a good injector should read between 10-14 ohms

 

yes as i have been reading i am starting to notice injector failure. I was an Infiniti Tech for about 2 years and seen very little injector failure.

 

injector 1 - 16ohms
2 - 11
3 - 11
4 - 11
5 - 0
6 - 11

5 had a cut wire aswell.. i taped it back up with electrical and got a new injector.. new one ohm'd out at 11.. car starts, runs and drives good. but rough idle before and now still.. thank you everyone for everything. and anyone have ideas for rough idle? i did do a complete tune up.

 

Cylinder one is a bit off.

What speed is it idling at?

 

500-800 but it goes up no higher than 900 and down to about as low as 3 for a second or 2.. then it sometimes stalls and 90% of the time it stays running. i noticed the throttle cable has a very little slack in it and the belt squeals.. if any of that info is helpful or just pointless.. but thats the only issues ive seen/heard

 

Belt squealing is probably the AC/alt belt too loose.

Ever cleaned your IACV? Do that and the TB, that's probably your problem.

 

well i cleaned the intake manifold ALOT of dirt/crap came out.. i never cleaned the IACV but i did clean the TB and i also noticed my car does have a little whistle under the hood.. i just dont know from where

 

Pull the IACV, clean it. Also test it per the FSM since you're getting the pending IACV code.

 

the whistle sound sounds like its coming from the EGR when i was putting it back together the gasket wouldnt stay on so i used black RVT to keep the gasket on while i got it in position to tighten down can that be it? or maybe i messed up wiring the emissions? the car idles fine until it warms up then it stalls and has a horrible idle

 

got codes p0100 and p0110 I'm headed to the shop to clean the maf and tb but any info is appreciated and helpful!!