Hey guys, let me give you the run down.

Last July I had to change my radiator cause the car over heated and turned off (g/f driving the car). Mind you it was 115+ out here. Car wouldn't turn on so we had it towed to the dealer. They replaced the radiator and 3 sensors; 2 cam sensors and 1 crank sensor. They said it would be best if the sensors would be replaced because the crank sensor failed (or did its part). Anyways... So a few months later in October I notice the car making a water splash sound inside the cabin. First thing I'm thinking is "great! they changed my coolant and it sounds like they didn't properly bleed it". So I bled it and it had lots of air bubbles. No more sounds!

Next, this is where it all begins. It seems that 25% of the time the car didn't want to start and had to give it a few cranks before it would turn over. This lasted a couple of weeks randomly through out the day. Didn't know what it could be. I went to Firestone because that's where I bought my Interstate battery and had them check it. I figured maybe it was going bad even though I purchased it 2 years ago. Well the battery turned out to be okay. I had them replace it regardless. Oh and every time they started the car, it turned over without hesitation. For $20 I had them do a electrical check just for ha has. Again, everything cleared to be okay!

So one night in February on the way home from the grocery store, I decided to go through my gears as I was merging onto the freeway. Everything was fine until I got off the freeway a couple of miles later. As I sat at the light, my idle was bouncing from 400~800 rpms. I didn't really think much of it, but when I was reversing into my parking spot, my rpms dropped down to 200-300 rpm and started bouncing up to 500 rpm. I thought the car would turn off, but it didn't. It was almost the same symptom as when I first installed my 5/16th spacer. So once again, I did a ecu reset and it didn't do anything. I added some injector clear and fuel treatment and it seemed to help a bit because it was idling smoother a week later.

Until the last couple of weeks the car has been fine. The problem that I'm having now is my car doesn't want to crank over right away, but rather a long abrupt crank. As soon as I'm about to stop cranking, it catches itself and does a rough idle for about 3 seconds, but smooths out right away. I feel like it's not running on all cylinders sort of speak. Through out my power band I do not have power from 3k - 5k rpm. It seems that I lose power at 3,250 - 3,400 and get it back at 4k, but lose it again around 4k. It's like it someone pauses my rpms. Also I get about 240 miles before the the fuel gauge drops to empty. This morning on the way to work I had a 1/4 tank of fuel left. 12 miles later when i got to work the light is on and its on the LAST line. I hear my fuel pump priming so I don't think its the fuel pump but who knows.

I ran it for codes using self diagnostics, and it gave me 10 blinks. Nothing wrong! I've searched and searched and all I can come up with is bad cam sensors and/or crank sensor. I have 1 day to fix this before I fly out so I am seeking for additional suggestions. Let me know what you guys come up with.

Here's what I did so far...
- Changed spark plugs = nothing (45k on them when swapped out)
- Added fuel treatment = nothing
- Checked air intake = K&N (good - cleaned few months ago)


Here's what I plan on doing...
- Clean TB
- Clean MAF
I highly doubt those things would help with my problem, but will try it later on.
- Check fuel pressure
- Reset all modules (air ration, throttle, ecu, etc)

My car is a 05 G35X with mods listed in my sig.

Thanks again.

 

Did Firestone replace the cam/crank sensors with OEM? If not I would suspect that's your issue and 1, if not more, of the sensors is causing the problem. Our cars are very finicky about OEM electrical parts.

 

Sorry it's such a long read, I'll summarize it when I get to work.

The only thing Firestone did was replace my battery do an electrical test. Everything checked out fine. I had the car at the dealer and they replaced all 3 censors. I'm within a year of warranty but over for mileage by 8k so everything is out of pocket again.

On the way home last night the car started up fine and drove fine but with more power than before, but still not how it should of been. I've had this car for almost 4 years and put over 110k. This is really the only mechanical problem it's given before besides what I have mentioned previously.

 

My first suspicion is that it's electrical in nature, and not sensor related. The slow, aburpt cranking wouldn't be an issue if it was a cam/crank sensor.

I was about to suggest that you could possible have a loose connection, or a bad ground. I then noticed you had a grounding kit installed. Personally, i'm not a fan of them because they tend to create ground loops and weird electrical issues. I'm from the school of thought that 1 good solid ground is better than 5 or 6 grounds.

So i guess my first question is how is the wiring in the car? Corroded? clean? etc?

 

The cranking is rather fast as if it doesn't have spark. I'll upload a video shortly for you to see. The grounding kit was installed by the man himself and it's been great since I think. I had it installed in September but only started to experience the problem in October. I thought it would be the starter since the car has about 159k miles on it, but it still performs fine. Plus what does it have to do with loss of power band, you know? Everything on the car is original except for the battery, radiator, the 3 sensors, and my small mod list. Can't say the car hasn't been good to me. Another thing that comes to mind is probably a coil pack or ignitor is going bad. Again, no codes.

My next option is the dealer, but i want to see if someone could steer me into the right direction before doing so. Appreciate the help.

 

Ok. So just to back up a sec

So when you go to start the car, the starter engages and turns the motor over. What you are saying is that this speed has always been the same and has never changed? The only think that changes is how long a period of time it takes before the engine fires?

If so, i'm kinda thinking Blue Dream nailed it and the issue is the sensors.

 

http://s241.photobucket.com/user/Chu...57443.mp4.html

http://s241.photobucket.com/user/Chu...417ce.mp4.html

I drive through construction day to day so it's collect a lot of dust lately.

 

I'll have to check at home. Can't really listen at work

 

I have no problem buying the sensors, but it'll run me $325 for all 3 sensors from Nissan. I don't want to replace them if I don't have to because they were just replaced about 20k miles ago. What are the chances of them going out and not throw a code? That's the frustrating part.

 

Ok, I guess i do have speakers on my laptop

That's not a starter, or electrical issue pertaining to the battery and such.


With 150K on the clock, i wonder if it's a fuel issue. However, no CEL, so you aren't getting a lean code.

Does your code reader have a menu option called "Pending Codes" Some code readers have these and some only read mature codes

With no CEL, it's possible you have whats called a pending codes. However, like i said, not all coder readers can read these. My Actron does.


I would suspect the crank/cam sensor, but would also go through your checklist of things to clean like the MAF and TB...as well as checking the fuel pressure. I understand not wanting to buy sensors without being 100% sure. I personally wouldn't do it myself until I was absolutely confident

 

Im in the same situation as you ..out of the blue came the long extended crank and rough idle, bog from 3-4k, I have been getting random codes such as p0300, p0171, o2 sensors, p0011, and others just random...so I took off my spacer because of a vacuum leak, changed the big 3 c censors, changed plugs, checked coils - spark, cleaned my maf, and TB ( bat was unplugged and MAF was disconnected - polished) one thing I did find it that my pcv valve was clogged from some thing in my catch can, changed it and she runs a bit better now but not at 100%...going to do the maf first, relearn, and then the TB- thinking the tb may have gotten messed up... all throught this process I have done the ecu resets and iac relearns.. ill let you know what I find. Im at 100k but I suspect its my maf, last time it was covered in just crud, cleaned it with maf cleaned but still hasn't been right since. I have two different code readers too, one finds some that the other one doesn't, I would check that as well...pending code as stated above.

This is the processed I did...
https://g35driver.com/forums/5354482-post17.html

 

I do not have a code reader nor does anyone in Cali rent them out like they do in the New England. This sucks. I did a quick search and did the pedal method. 10 blinks = 0000 No Codes. Again, I can bring it to the dealer, but they'll charge me $130+ just for the diagnostic and if it is the sensor I will be pissed off. I've been meaning to get myself a nice OBDII scanner as I do all the work myself. I'll have to invest in one really soon. And with the loss of power through out the power band and minor rough idling it could possibly be the MAF and TB, but with my cranking issues I think there's more to it.

I have fuel pressure also listed because to me it seems like the fuel gets sent back to the tank and when I start the car there isn't any spark. Could be a bad fuel pressure regulator and/or a valve that isn't doing it's part by keeping the fuel in the lines (forgot the name).

 

At least you have the codes to go by. But here's a suggestion for you. Try to fix it one step a time. By doing multiple steps to fix it, you can create more problems or you'll end up spending more money on something you don't know what fixed your problems. Be patient and start with one code at a time and see where that leads you to. Good luck on your problem and let me know how you make out.

 

hey I say swing by an auto zone and an advance they should do free code reading they may have different scanners as well, worth a shot. To you above statement same thing I thought but I went back to basics to try to figure it out...spark, gas, air I'm thinking we both may have the same issue...lack of air. A/Fr is off... IF I had to pick between the two MAF>TB...imo

 

Thanks, yeah did that and by process of code elimination is what brought me down to the maf /tb...I currently don't have any codes and none show after drive cycles, ecu and relearn has been done. still bogs at 3-4k, crank has gotten shorter, but still extended, idle is still hoppy, only thing really left is maf, tb, and a stealership colonoscopy ... But ill let you know what changes after tomorrow.