G35 Coupe V35 2003 - 07 Discussion about the 1st Generation V35 G35 Coupe

g35 misfiring... what do you think?

  #1  
Old 04-08-2017, 02:50 AM
Registered User
Thread Starter
Join Date: Oct 2016
Posts: 12
Received 0 Likes on 0 Posts
g35 misfiring... what do you think?

Hello guys I have an 05 Infiniti g35 Coupe with 113,000 miles.
All was well until one day the G started misfiring heavily and went into limp mode. Thankfully my parking spot was 20 feet away, and at that point I parked her and she sat there for months until I had time to diagnose.

----------- months later --------------------------------------------------------------------------------------------

put new gas in and right before giving up she started back up, but was in limp mode, couldn't get over 10mph or 1500rpm.

a week or so later I brought the G to a local mechanic who then told me my timing chain was broken... lies

I then towed the G back to my garage and began my own diagnosing...

changed:
spark plugs (found oil in 4 and 6 assuming it's the valve cover, planning to change this week)
Crank position Sensor
PCV
Oil change
Full tank of high grade fuel with Lucas fuel injector cleaner
Clean MAF
checked for vacuum leaks with a stethoscope (none)

At this point she was running again but would misfire at various rpms, but not without load.

I didn't know what to do next so I took the G to infiniti for guidance.

They ran a diagnostic and returned to me with two codes that they presumed to fix the misfire.
p0345 Camshaft position sensor bank 2 and
p1283 upstream air to fuel ratio o2 sensor

and also a code for the spiral cable.

I went to the auto parts store and bought the two sensors, both OEM and then proceeded to install them.

After installing she started up well and sounded good in park, but as soon as I put her in gear she misfired horribly. It sounded like marbles being dropped into a tin can.
Then I checked the spark plugs and all were clean but 4 and 6

changed coil packs for 4 and 6, but the symptom continued so I then swapped the old CPS back in and the misfire code went away but this misfire did not. but new codes appeared.


P0345 CPS
P0037 Heated oxygen
P1065 ECM backup circuit

my thoughts are it could be the fuel injectors, fuel pump/filter or the ecm is bad. another theory is that one of the resonated pipes on my exhaust has deteriorated inside and causing restricted flow and a bad reading for the o2 sensors.
Where should I start or should I go back to infiniti...


any input is appreciated. thank yaa
 
Attached Thumbnails g35 misfiring... what do you think?-fullsizerender-2.jpg   g35 misfiring... what do you think?-img_0918.jpg   g35 misfiring... what do you think?-fullsizerender-4.jpg  
  #2  
Old 04-08-2017, 08:16 AM
Urbanengineer's Avatar
Super Moderator
iTrader: (3)
Join Date: Jun 2013
Location: OH-IO
Posts: 9,967
Received 807 Likes on 758 Posts
Sounds like leaky valve covers. Thought I'd see an old rusty 200k mile G, this is too nice not to be running!
 
  #3  
Old 04-08-2017, 09:35 AM
Registered User
Join Date: Mar 2011
Location: Central NJ
Posts: 2,035
Received 117 Likes on 105 Posts
Originally Posted by Tristan Laravea View Post
........

I didn't know what to do next so I took the G to infiniti for guidance.

They ran a diagnostic and returned to me with two codes that they presumed to fix the misfire.
p0345 Camshaft position sensor bank 2 and
p1283 upstream air to fuel ratio o2 sensor

and also a code for the spiral cable.

I went to the auto parts store and bought the two sensors, both OEM and then proceeded to install them.

JAMIN:
So far so good!


Originally Posted by Tristan Laravea View Post

After installing she started up well and sounded good in park, but as soon as I put her in gear she misfired horribly. It sounded like marbles being dropped into a tin can.
Then I checked the spark plugs and all were clean but 4 and 6

changed coil packs for 4 and 6, but the symptom continued so I then swapped the old CPS back in and the misfire code went away but this misfire did not. but new codes appeared.


P0345 CPS
P0037 Heated oxygen
P1065 ECM backup circuit

my thoughts are it could be the fuel injectors, fuel pump/filter or the ecm is bad. another theory is that one of the resonated pipes on my exhaust has deteriorated inside and causing restricted flow and a bad reading for the o2 sensors.
Where should I start or should I go back to infiniti...


any input is appreciated. thank yaa
Why didn't you return to the dealer instead of guessing?

Perhaps your cats are clogged but continuing to replace random parts by guessing without a pro to find the root cause on a 12 year old vehicle is going to be a huge waste of time and money.

Just my $.02

Telcoman
 
The following users liked this post:
Tristan Laravea (04-21-2017)
  #4  
Old 04-08-2017, 09:49 AM
Blue Dream's Avatar
I drove ttrank's car solo
iTrader: (50)
Join Date: Mar 2009
Location: By the sea, Tx
Posts: 18,194
Received 1,434 Likes on 1,182 Posts
G35 sedan w/ too much money in mods
You said you bought OEM sensors at an auto parts store but in my experience that isn't possible. Our cars don't usually play well with aftermarket sensors so you might check into that but I'd probably take it back to the dealer for a true diagnosis before replacing anything else. I'm not usually fan of the dealership but sometimes they're our best bet.
 
The following users liked this post:
Tristan Laravea (04-21-2017)
  #5  
Old 04-08-2017, 04:37 PM
Registered User
Thread Starter
Join Date: Oct 2016
Posts: 12
Received 0 Likes on 0 Posts
Hey guys thanks for the responses! and yes it is probably more effective to bring to the dealership to have them fix it, but as I may have not made clear I already did. They told me to replace the CPS and the upstream 02 sensor. I could have payed them to do it but they wanted over $1,200. I figured I could do exactly what I would be paying them to do but for 1/6th of the price. Plus, everything I tried after the fact was of low cost. The G actually only has resonated test pipes leading to the cat back so maybe something is loose in there. In regards to the sensor response, from my knowledge many auto parts stores do sell OEM parts, my concern is that maybe I got a dud, even though it is unlikely, I personally know it is possible as on the old motor I installed a new OEM sensor and it didn't work, bought another new one from somewhere else and it fixed the issue. Needless to say its electrical, there can be flaws
 
  #6  
Old 04-08-2017, 10:01 PM
partyman66's Avatar
Registered User
iTrader: (1)
Join Date: Jul 2004
Location: Southeastern Mass.
Posts: 3,559
Received 222 Likes on 195 Posts
Test the sensors you bought. Typically the FSM has a test procedure for most sensors.

If you have a Bluetooth OBD-II reader you can also look at real-time voltage readouts from each of your oxygen sensors and see if one is bad as well as see the readouts from many other sensors.
 
The following users liked this post:
Tristan Laravea (04-11-2017)
  #7  
Old 04-11-2017, 10:24 PM
Registered User
Thread Starter
Join Date: Oct 2016
Posts: 12
Received 0 Likes on 0 Posts
I do have a bluetooth reader so I will check that out when I get back in the states! putting my issues on hold for a week out here in Barbados
 
  #8  
Old 05-08-2017, 11:05 PM
Registered User
Join Date: Nov 2015
Location: Durham,NC
Posts: 76
Likes: 0
Received 2 Likes on 2 Posts
I had a problem similar to this. The problem with mine was anytime there was a large temp change in the weather the car would start misfiring and would run pretty rough for a while. Then the problem would disappear. I tried all kinds of things, plugs injectors, injector cleaners. This drove me about mad. I even thought I fixed it a few times.

In the end it was a faulty relay. It finally went out and the car went in limp mode. Unfortunately this relay is on the relay box(what ever its called) behind the battery. Even though the relay is fairly common on nissan/infiniti vehicles, it is always on that box. The dealer wanted like 600+ for the relay box and did not sell the relay by itself. It was not sold at parts stores either. So I hit the junk yards and looked in every vehicle till I found the relay and grabbed like 20 of them .

I no longer have the car now, but I still have the relays. I will see which one it is and post it here tomorrow, maybe it is the same problem you have. Unless you fixed it already.
 
The following users liked this post:
Tristan Laravea (06-11-2017)
  #9  
Old 05-09-2017, 07:44 PM
Registered User
Join Date: Nov 2015
Location: Durham,NC
Posts: 76
Likes: 0
Received 2 Likes on 2 Posts
It is the OMRON model G8VL-1A4T-V relay. I see them on ebay for 12-30$. I should sell mine. I may have 20 of them
 
The following users liked this post:
Tristan Laravea (06-11-2017)
  #10  
Old 06-16-2017, 02:16 PM
Registered User
Thread Starter
Join Date: Oct 2016
Posts: 12
Received 0 Likes on 0 Posts
hey thank you for sharing your experience! Could you please clarify the symptoms you were having as far as the misfire? I live in Florida and its pretty consistent with temperature, but **** if it could be as simple as a relay, how would one diagnose this? Or is changing it the only way to know? I have been to infiniti dealership and they said nothing in regards to the relay.
 
  #11  
Old 06-16-2017, 02:33 PM
Registered User
Thread Starter
Join Date: Oct 2016
Posts: 12
Received 0 Likes on 0 Posts
UPDATE:

so I have been traveling a lot and working, but finally got a chance to save up some $$$ and planned to take it to the dealership to get raped financially, but leave with a working G.

So I towed her to infiniti and they began to run another diagnostic. I wanted them to spend a few hours to check everything under the hood to give me a detailed description of all the things I could replace.

so i get a phone call and they tell me to come in and have a meeting with them about my car.
they begin to tell me the car has been worked on so much, yada yada yada. and that the harness is extremely damaged, and need too be replaced before they could tell if it was the ECU or not.

note there are no codes being displaced other than the p0300.

So after hearing this I got the G towed home.

finding a used harness from a G for about 150 bucks, and my buddy and I swapped it in about 4 hours, without pulling the engine. no change in the misfire.

actually to our surprise, or maybe not, the replacement harness and the harness that was originally on the were practically identical. I couldn't find any signs of "damage". so that pissed me off especially after infiniti said to repair it, it would take them up to 10 hours! @ $150 a hour! WTH.

now that I am sure it is not electrical,
after checking to make sure the following are good:
spark plugs
coil packs
no vacuum leaks
CPS sensor


now I believe it could be the fuel injectors or the fuel injector harness, plan to change those this week.

Infiniti did mention my ECU could be bad, but given how honest they are, I question it. I get no codes referring to the ECU and my misfire is only on acceleration, not in park or idle.

I think its injector related because I had a very interesting idle, It almost seems like a cylinder is cutting in and out in addition to one being out all the time. needless to say she is driving extremely sluggish. Also, spark plugs 4 and 6 have black tips, indication improper combustion.'




I would hope this is the end of the saga, simply I am not sure what else could cause this.

If anyone has any input, similar experiences or any experiences relating to bad fuel injectors please feel free to share, it would be greatly appreciated!
 
  #12  
Old 06-16-2017, 10:05 PM
Registered User
Join Date: Nov 2015
Location: Durham,NC
Posts: 76
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by Tristan Laravea View Post
hey thank you for sharing your experience! Could you please clarify the symptoms you were having as far as the misfire? I live in Florida and its pretty consistent with temperature, but **** if it could be as simple as a relay, how would one diagnose this? Or is changing it the only way to know? I have been to infiniti dealership and they said nothing in regards to the relay.


Sorry for late reply. My experience with relays is they won't throw a code until they fail. But I have not had many fail on me, actually this was the first one . I will copy and paste what I put in another thread and other things I found/did when I was trying to figure this out.

One day last week when I started my car up it was idling fine. When I started going down the road(without letting it warm up) it started running like it was missing. I had a bad smell coming from the exhaust(full throttle burt cat smell). The check engine light was also blinking erratically. I pulled over and checked and made sure no electrical plugs around the spark plugs was loose or unplugged. They were not. The car went back to idling fine, no flashing check engine light and drove fine and pulled as normal. The car was also warmed up by now. No problems until today.

The same thing happened today as well. Started it up, it idled fine, 30 secs later it was running like before. But now I have a constant check engine light, it blinked a lot like before but now constant. I am going to pull the intake pipe off tomorrow and make sure again I did not overlook something from last week. Then will slide down to the parts store and have them pull the codes to see what it threw before I pull the plug packs and plugs and reseat them. That is the only thing that has been touched in this time period. After the car warmed up(or shortly after it was running fine again).

I would like to note that the two days that this happened was a decent change in the air temp outside and I am wondering if that has something to do with it. The first time was over a 40 degree change. I would like to get some opinions and will follow up tomorrow with what codes were thrown. I have worked on my own cars for a long time but I am not a mechanic by no means especially when it comes to the ecu part of it.
checked pvc valve, not the problem but didnt hurt to check
Later on I pulled the recently replaced plugs and checked them. They looked fine, also checked coil packs, MAF. Nothing changed.
After all this finally got a code. Ended up being cylinder 4 misfire and nothing else
Switched plugs and coil packs with a working cylinder to see if one of those two was the problem. The problem did not shift to the working cylinder. I figured it must be the injector sticking. Also contacted a tech at one of the local Infiniti dealerships. He stated it sounded like a sticky or faulty injector and suggested running some industrial injector cleaner they use. Tried it, Seemed to work, problem returned a short time later.
This went on and off for a little over 3 months. The first few times this happened there was a somewhat large temp change, which had to be an electrical problem somewhere. I was even thinking maybe the ecu was going out. One day it started missing again, then immediately went into limp mode. I was able to get it home and pulled the codes.

I can not remember what the exact code was, but it pointed to a relay on the box behind the battery. It is called the IPDM. It took me quite a while to find this silly box from wiring diagrams and also calling Infiniti to see what the name of the box was. BTW it was like 700$ give or take from them. They don't sell the relay's nor anyone else. Which is bothersome because this one is used in a ton of applications. Image below for the location and what it looks like.

There were times where it misfired for a couple seconds to several minutes. I fixed this last mid year and never had a problem with it since. TBH I am not sure how or why that caused a misfire. I checked a schematic of the box and I was even more lost. I can not remember which specific relay it was, but I think from looking at this picture it was one of the lower right 2 which is the Throttle control motor relay and ecm.
 
Attached Thumbnails g35 misfiring... what do you think?-2015-05-27-18.56.03.jpg  
  #13  
Old 06-16-2017, 10:37 PM
Registered User
Join Date: Nov 2015
Location: Durham,NC
Posts: 76
Likes: 0
Received 2 Likes on 2 Posts
I forgot to add, not only did I replace the injector, I also switched it around with other cylinders to verify it was not a sticking injector with no avail.
 
  #14  
Old 06-21-2017, 04:14 PM
Registered User
Thread Starter
Join Date: Oct 2016
Posts: 12
Received 0 Likes on 0 Posts
well guys I just did a compression test and it looks like my cylinder 4 is low. 75 to be exact, the others all were 210. I added a little oil to cylinder 4 and tried the test again, no change. does this mean head gasket? and at this point is it better to swap a new motor, being that the head gasket went out once, it may go out again after being repaired.? or should I just sell the thing as is :/ I don't want to but might have to if it doesn't get resolved soon.
 
  #15  
Old 06-21-2017, 05:27 PM
Texasscout's Avatar
Registered User
iTrader: (11)
Join Date: Feb 2005
Location: South Texas
Posts: 31,727
Received 1,625 Likes on 1,299 Posts
My Nissan Frontier started that, it was the crankshaft position sensor. But, mine threw the code for it.
 

Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: g35 misfiring... what do you think?


Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: