G35 Sedan V35 2003-06 Discussion about the 1st Generation V35 G35 Sedan

Rough Idle on my '05 G35

  #31  
Old 12-03-2014, 12:00 AM
westsideblu's Avatar
Registered User
Join Date: Mar 2014
Posts: 246
Received 22 Likes on 22 Posts
Originally Posted by Mustang5L5 View Post
For a cheaper alternative to G35 valve covers, look into maxima covers. There is a write up on here.

They are half the price.
This is a good thing to know I can swap my valve cover with cheap ones when I decide to paint them.
 
  #32  
Old 12-03-2014, 09:01 AM
G2B35AGN's Avatar
Registered User
iTrader: (9)
Join Date: Mar 2013
Location: Raleigh, NC
Posts: 1,303
Received 179 Likes on 159 Posts
Coupe, Premium package, sport suspension
Originally Posted by westsideblu View Post
This is a good thing to know I can swap my valve cover with cheap ones when I decide to paint them.
Not quite a swap...you have to do a little bit of drill out and install an o-ring kit for the plugs.
 
  #33  
Old 12-03-2014, 12:16 PM
westsideblu's Avatar
Registered User
Join Date: Mar 2014
Posts: 246
Received 22 Likes on 22 Posts
Actually the maxima vcs swap over just some of the mounting tabs and the oil cap hit the stock plenum and they rotate a few of the coil packs so if your stock you have to extend wires but I did a wire tuck so I got all the wire in the world until I move the hole by the battery and shave the bay
 
  #34  
Old 12-04-2014, 07:26 PM
Registered User
Thread Starter
Join Date: May 2012
Posts: 37
Received 0 Likes on 0 Posts
UPDATE:

sorry its been a while guys. Ive been really busy this week.

I went to o'reilly today and rented a compression checker (since my other one broke after only testing two cylinders). The ones you can rent are built way better than the cheap ones you can buy locally.


here are the compression results, note I did 9-10 full cranks each time:


Cylinder 1: ~151 psi
Cylinder 2: ~170 psi
Cylinder 3: ~60 psi (tested twice, second time I did 15 cranks and it got up to 84 psi)
Cylinder 4: ~164 psi
Cylinder 5: ~171 psi
Cylinder 6: ~158 psi


so, well thats great. My compression checker broke so I assumed compression was fine. Sure enough I try it again after I bought all this stuff and its down really far on cylinder 3


Hanes manual said if one cylinder was "slightly" lower than the others (idk if slightly means cut in half) then its probably worn camshaft lobes.

It also said it if compression was low on the first stroke, followed by it not building on successive strokes, then it could be leaking valves, blown head gasket, or cracked head.

So im not really sure what to do right now. What do you guys think is the most likely cause? Do I need a new engine or is this something I can fix myself at home?


gosh im so mad that my compression checker broke that first time. could of avoided all of this. ugh. If i ever have a misfire in any car again and its not spark plugs I will be sure to do a compression test first before anything else and on all of the cylinders...
 
  #35  
Old 12-04-2014, 08:46 PM
Mustang5L5's Avatar
Registered User
iTrader: (1)
Join Date: Jul 2005
Location: Taxachusetts
Posts: 8,821
Received 451 Likes on 377 Posts
Add some oil to that cylinder and recheck it. If the pressure comes up, it's rings.
 
  #36  
Old 12-04-2014, 09:10 PM
Registered User
Thread Starter
Join Date: May 2012
Posts: 37
Received 0 Likes on 0 Posts
Originally Posted by Mustang5L5 View Post
Add some oil to that cylinder and recheck it. If the pressure comes up, it's rings.


how much oil should I add? will do it Tommorow morning.
 
  #37  
Old 12-05-2014, 08:32 AM
Mustang5L5's Avatar
Registered User
iTrader: (1)
Join Date: Jul 2005
Location: Taxachusetts
Posts: 8,821
Received 451 Likes on 377 Posts
Not too much. Just a few squirts should do it.

Basically you are doing a compression wet test

http://www.freeasestudyguides.com/co...cting-oil.html
 
  #38  
Old 12-05-2014, 11:51 AM
Registered User
Thread Starter
Join Date: May 2012
Posts: 37
Received 0 Likes on 0 Posts
Originally Posted by Mustang5L5 View Post
Not too much. Just a few squirts should do it.

Basically you are doing a compression wet test

http://www.freeasestudyguides.com/co...cting-oil.html
I didnt see your post this morning, so I went with the information that I found last night.


I found 2oz of oil to be enough. (and it looks like your post said that too)

I didnt know however, that i was supposed to do only 3 cranks with oil after doing the normal 7-10 cranks after a dry run.

but nevertheless here is my results, I am letting car sit for a while for that oil to drain, then I will go do the test again properly.

RESULTS:

each attempt what done right after the next, i did it once, released pressure and tried again.

I first poured approximately 2oz of oil into the cylinder. I then put the compression tester in and went around to crank the engine 9 times, except for the third time I did it, which i cranked it 15 times.

First attempt: 85 psi
Second attempt: 67 psi
Third attempt (15 FULL cranks): 154 psi

I then let the engine rest for 10 minutes. I then poured 1 oz of oil into the cylinder. reason why is because when I did 2 oz, the car wouldnt even crank without a few tries. it would try to, but just stop, but after 3 or so tries it began to crank.

First attempt (1oz, 9 cranks): 40 psi
Second attempt(9 cranks): 49 psi
Third attempt (only 9 cranks this time between 2nd and 3rd attempt): 115 psi

seeing it was building, I did a 4th attempt with 20 full cranks and it got up to 255 psi...


very confusing results as it seems to build pressure only after it has cranked a few times.... but again, I did this test wrong in the first place so I am not sure if it can even be used for results.

The oil I used was some Mobil 1 high mileage I had stored. I noticed when I pulled the compression tester out it had these foamy bubbles on it, not sure if it is from the oil or something else.



DO NOTE: the bubbles are above the gasket because I turned the compression tester upside down when I pulled it out. No, it did not leak.
 
  #39  
Old 12-05-2014, 04:47 PM
Registered User
Thread Starter
Join Date: May 2012
Posts: 37
Received 0 Likes on 0 Posts
I repeated the compression test several times. Despite the wait, the oil doesnt seem to be draining, or the rings are still wet.

PSI remains above 120 on that cylinder due to this. Im suspecting the rings are the culprit.

But my only question left is, why am I seeing a random/multiple misfire and not a single misfire on cylinder 3? The engine will not run at all without hitting the throttle. IT will idle for a few seconds after hitting the throttle, but eventually the revs slow down and eventually stop.
 
  #40  
Old 12-08-2014, 08:30 AM
Mustang5L5's Avatar
Registered User
iTrader: (1)
Join Date: Jul 2005
Location: Taxachusetts
Posts: 8,821
Received 451 Likes on 377 Posts
V6;s tend to struggle a bit when one cylinder is dead or not functioning well. A V8 can lose a cylinder and not even feel a thing.

You'll def want to run the engine and burn that excess oil out. I wouldn't go too crazy trying to comp test shooting oil in. I'm not sure i can take away that the rings are the culprit just yet.
 
  #41  
Old 01-02-2015, 12:33 PM
Registered User
Thread Starter
Join Date: May 2012
Posts: 37
Received 0 Likes on 0 Posts
Thanks guys for the help, but after some thought we decided to swap the engine.

We found a used VQ35DE with 39K miles for a good price (about $1400). So we went for it, had a local guy swap it for us. Car is running good now, just getting a lean reading from O2 sensors, not sure why but I'll make another thread on that.


anyway, thanks!
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
netcbc
Exterior - Body Parts CDN
2
08-21-2015 09:50 AM
VANST3R
Lights
2
07-27-2015 08:20 PM
Rehman2009
General Tech Questions
3
07-27-2015 03:23 AM
laksjd84
Exterior - Body Parts
1
07-24-2015 05:12 PM


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: Rough Idle on my '05 G35


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: