Truck hazes white at idle
- Thread starter RENODMAX
- Start date
Try raising your rail pressure with DVT tool at idle. See is haze goes away
I have done two LB7 lately that had haze at warm idle but everything checked out great. Raised pressure to 6500 and bumped timing from -3. to -1.
Worked great.
Raising idle rail pressure and timing would give better atomization and burn. Only reason I can think that your truck would start to haze out of nowhere would be the injectors getting farther out of tolerance, or "loosening up" so they need more pressure/timing to stay clean, especially at idle. Just my thoughts.
I was just thinking/typing out loud about the better burn with timing/pressure. Sorry.
You could always send the injectors out to be tested? I've had a haze at idle for the last few years, everything checks out fine, so I've quit worrying about it to be honest.
My dads 02 does this also it has about 235,000 on the original injectors. Good balance rates, no fuel in oil, CP3 passes test at 158mpa has a new frpv.The reason the balance rates show normal is all nozzles are worn/plugged equaly causing poor atomiziation from what I was able to find out. Maybe give it hell on the real injector flush/cleaner. Not sure how good it works but BG makes a flush that runs only on the cleaner itself instead of adding it to the tank. There may be other brands but I'm not sure.
I was just thinking/typing out loud about the better burn with timing/pressure. Sorry.
I'm gonna drive it til it blows. Then it's motor time
Yeah they turned me down a while back too. WTF. Called gm customer care so well see. If it doesn't work she's getting a built Lilly
That sounds better!
Yeah I called GM and told them I didnt like chevys service and they let me transfer over to GMC. Its worth a shot until you build another motor.
It sounds like you have an injector not fully seating any more and its dribbling fuel into the cylinder when its supposed to be closed.. Get it hot to where its smoking at idle, pull all ur glow plugs, pull your #5 edu relay or the ficm plugs, using a starter button or the ign key crank the engine over and look for puffs of fuel/smoke out of glow plug holes, wear safety glasses, use cardboard if you dont have a couple buddies to help look on both sides while cranking. That will show you who the leaker is. As for warranty, it wouldn't matter if your truck was bone stock GM doesn't cover LB7 injectors for this type of wear. Just do Like I am doing go with a LLY swap, for the same money as a set of injectors.....problem solved!
I like this answer way better than mine, seemed that the info I got just didnt sound quite right. Wouldnt this one show up on balance rates though as the cylinder with the leaky seat be trying to pull fuel showing a higher - on the balance rates? Or the smoke would quit when cutting cylinders unless its more than 1 leaky one.
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That's wht I plan on for my future if you read my earlier posts. I've really liked some of the llys I've tuned. Very smooth trucks
I've had them dribble enough to puff vapor out the holes and show no real signs at a balance rate inspection, older ecm's aren't sensitive/fast enough to detect IMHO. I've even had injectors cause the engine to vibrate badly by just barely touching the gas pedal and I mean just breathing on it, anything more and it went away, it also had no signs of BR issues. Who knows what goes on inside an LB7 they are special creatures. :rofl: