I noticed today after rapping up 1st gear really fast WOT, I heard a slight noise (can't really describe it), but i have a feeling it was my belt starting to shred from the quick spool up and RPM change. I have now changed my belt after the first strand had started to go. I put on a Gatorback, and the noise has not come back at all yet.

So as i was driving back to school, i was idling at a stop light and the truck was vibrating more and on and off, also you could hear a difference in the idle. After checking vitals (i know our dummy gauges, but they read good) i watched the tach. and every time it would start vibrating more (slightly, feels as if its running rougher) and sound a little different the RPMs dropped a bit. I turned off all my accessories (just the radio at the time being) thinking maybe im having a charging issue. Not the case. So i turned on the A/C to see if maybe the clutch in that is having an issue, again not the case, it surged with it off and on. The surging is also random, no pattern to it that i can tell.

Another item worth noting, i popped the hood when i got home, let it idle for a minute or two while i was listening in under the hood. I go and turn the truck off with the ignition, and go back under the hood, and I can hear a leak (sounds like an air Hiss) of something coming from the passenger side.

Wondering what your guy's ideas are.

The truck does have a CEL, but its been on for about a month now, My drivers side glow plugs are reading too much voltage indicating a few are bad. Have not changed them yet, so the CEL keeps coming back. Would an idle issue like this possibly have set a code, but i dont know since the CEL was already on?

Thanks

Matt

 

The AC compressor is on all the time except for 'vent'. So it may still be the compressor causing the surge.
The AC will make a hissing sound right after shut down, not sure what it is though?

The hissing noise might be vacuum. The HVAC unit always defaults to defrosters with a loss of vaccum. Place your HVAC controls to anything other than defrost when you shut it down....after the hissing stops fire it up again, be sure to turn the fan motor all the way up, hold you hand over the defroster vents and fire it up. If you feel air at the defroster then it changes by itself, the noise is vacuum hissing.

 

I will go try that now. I have it set on the off postion when i shut it down. Ill fire it up and see if its blowing out the top with the fan on High, but it still on the OFF position.

I dont think this is an issue though, because everytime I fire the truck up each morning, the fan is normally on High and the OFF Position and there is no air flow coming out of the defroster.

I did try the A/C today for the first time (had the truck a month) and it blew colder than any of our other cars. Not to bad for 212K miles.

Be right back to check to see if it is switching to the defroster and maybe to get a video.

 

Off won't work, the fan will doesn't blow in that position IIRC.

 

Okay, ill try it agian in a different setting...

but i just shut the truck down and did not hear any hissing or noises after shutting it off.

I did take a few videos on my phone (crappy quality) i am uploading now.

another thing i decided to do was take the oil cap off and smell for burned wires. No smell of burned wires, but it was smoking out of it when i took the cap off. I dont have a clue what that is about, unless the oil is being burned (dont know last oil change, been meaning to do a Rotella 15W40 change on it)

 

That's blow by, normal for most engines, especially turbo charged...but, there shouldn't be too much coming out when its running. The Crank Case Vent (CCV) evacuates those fumes by sending them back into the intake and burns them. Kinda like a PCV on a gasser.

 

okay that saves me... none of my race car engines have smoked from the valve cover (n/a nitrous motors)

here is the first video that is done,

dont think you can really tell from it though,

two more to come

http://www.youtube.com/watch?v=RKTLaiSuLLc

 

YouTube - Idling Powerstroke Diesel 97

 

Can't really see much in the vids except the idle is not that bad watching the tach, for an old truck and all it's faults.

 

Yea affaid that you would not beable to see anything. I love the truck, makes gobs of power, and rides nicely... just wish my ZF tranny syncros in 1st and 2nd were better (double clutching FTL)

Guess ill just keep driving it,if something changes ill post thats for sure.

 

Well update...

took the truck to my buddies house across town tonight (25 miles). Highway driving most the time, but when i was going slower (less road noise) i could hear the turbo spooling up. I have never been able to hear this before. This has me thinking that the cause of the missing(running rough, surging slightly, what ever you want to call it) is from a tube or something that broke.

I also tested the A/C trick. I used the a/c all the way to my buddies house on full blast and then turned the truck off. When i fired it back up three hours later, it came directly out of the vents, and not the defroster.

So what could have i blown off or done to cause it to run differently at 0 throttle?

I also noticed no change in power at all, truck hauled *** as normal.


5th Gear on the highway is fun... had the speedo way past 85 MPH on my 35s, so i was really going much faster, at about 3100 RPM. I dont have a PRYO gauge yet, but should i worry with a stock tune on the truck with my EGTs?

 

I would love to know the answer to the surge issue. Mine does the same thing. Has done it since I bought it about 2 months ago. It is more annoying than anything.

 

isnt that just the fan belt sking or but pulley bearing hard to tell

 

Take a look here for ore info on idle quality
Oregon Fuel Injection, your diesel fuel injection specialist, rebuilt turbochargers, injectors, pumps and diesel performance products.

 

I'm wondering, maybe the engine is running just fine. And the vibration I am feeling is a loose cab mount or something similar that randomly something is touching the cab making it viberate. Will look into it some more this afternoon after school.