Rough idle no codes yet, worst when cold

silver04v

silver04v

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Like the title says. It's pretty cold here in New Hampshire, this past week my idle on startup has gotten much worse. It's had a little stumbly feel for awhile now, and now if you rev it cold she comes down to idle real rough, almost stall rough. No dtcs yet. I checked plugs, look fine. So I decided to check my valves. 111k. The first intake I checked by the specs I found at my work(identifix) I'm 3 thousands to much on intake, and that's hot too. So, 4-5thousands cold?

I'm a master tech for Nissan but honestly have no experience in valve adjust cause that's just not a thing on Nissans.

Do we have valve specs on the forum here anywhere that I might be missing?

What's everyones thoughts? I also hear a bit of clicking when cold under revs. Car runs 90% normal after it warms all up, every now and then a little stumble here and there maybe. But revs and idles ok..little lumpy maybe in idle sound out exhaust, like light pops.

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.009 on intake side
.010 -.011 on the exhaust side

from honda below. From your description, I'd say you def need to adjust the valves. Others have said just 2 thousands out and it can run poorly.

val1.png val2.png val3.png
 
Welcome. Let us know what your specs are if you would. I’m curious to see how close your specs are at 111k miles.
 
Oh for sure. Yeah, the two intakes i checked today were at .012-.013 and that was pulled apart at operating temp. So however long it took to tear it down...like 20 mins or so they are only going to get bigger when cold. So Im already .003-.004 out as is.
Im hoping for a complete fix here and the problem fixes the symptoms Im having. So far its all adding up.

Cars has been 2/3 highway, 1/3 back road driven its whole life. Never babied. Redlines a lot. So its turned fast many many times. Hopefully all goes well and I have good reports tomorrow.
 
Yeah make sure to do it cold. Honda made me leave a car overnight when I was traveling so they could do it in the morning. I was over 1k miles away from home and was under warranty (car was running really rough)
 
webby said:
Yeah make sure to do it cold. Honda made me leave a car overnight when I was traveling so they could do it in the morning. I was over 1k miles away from home and was under warranty (car was running really rough)
Click to expand...
Oh wow, still under warranty. Damn. Yeah, Id say the last 40k its had a rougher idle, and i thought i should do it..but now its getting REALLY bad. It was time to check. Yeah, Im driving to work, open hood outside...20*F and then ill push it inside 4 hours later or something and tear in.
 
It was on another Honda that had a warranty valve adjustment TSB or whatever. I was driving in some higher elevations and the car was dying out on me.
 
Son wasnt feeling good, so I had to stay home today. Hopefully I'll be able to get it done tomorrow at work.

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So all my exhaust was tight. Some tighter than my .006 feeler gauge. So that's odd, I'd expect them to loosen but was once before told I'd probably find them tight. Anyways, intakes varied but average I found them at .011-.013. So those were a bit loose.
I set intake to .009 and exhaust to a loose .010
So far was running real smooth on the initial cold start after the work. Drove it home 52 miles and it was real good, however blizzarding at the moment and hard to gauge anything. But yeah, time will tell but so far it looks optimistic.

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Yeah, sounds like they were all in need of adjustment. It’s wild how just a few thousandths can make that much of a difference. It did in my case too.
 
webby said:
Yeah, sounds like they were all in need of adjustment. It’s wild how just a few thousandths can make that much of a difference. It did in my case too.
Click to expand...
For sure, I'll keep this updated over the next day or two. Thanks for the info again, made it a breeze. Very easy procedure.

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Another day of very good results. No issue this am in the cold after sitting overnight. It would almost die if reved cold, until well after the blue light goes out.
No issues at lunch..
And there is absolutely a noticeable difference in low end power and response. This thing has been out for awhile now. The exhaust being .005-.006 when spec is .010-.011 is pretty substantial and then backed with intakes out of spec by .002-.003.
I thought maybe I was making it up but no..definitely had some power loss from this. Even the sound of the engine on the highway rolling onto 6th is more smooth sounding.
 
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