98 12 valve low rough idle
 

My 98 12 valve when it sits overnight i go to fire it up and it only idles at maybe 500 rpm and has a blueish haze and smells very rich also idle is a little rough..after about 10 seconds it climbs right up to 800rpm.. blue smoke goes away when truck is warmed up and truck idles at 850rpm when warmed up.. it only happens if truck sits more than a couple hours.. do i need to turn up idle maybe? Or is lift pump going out? Ofv was replaced same as fuel filter and pre screen..thanks!

Mine bacicaly does the same thing.
I asked a shop i know about it and they said thats normal for a 12 valve.
What's happening is while the motor sits a little fuel will leak out of the injectors and set in the cylinder until the motor is started again. That blue smoke/haze is the fuel in the cylinder being burned off.

Ok i was just wondering because when i first bought truck it didnt do it at all no smoke so low idle fired right up to 800 rpm.. then i advanced timing turned starwheel and put new plate in and now it does it.. do dont know if i caused it lol... also is it normal for my oil pressure gauge not to show oil pressure for about 5 seconds after trucj starts?

Mine was almost identical to yours. Mine didn't do it, then i modded it then it started doing it.
As for your oil pressure gauge, mine goes up right after i start my truck. So you may have another issue starting, not sure? Hopefully someone can help in this.:humm:

I would say you need to up your Idle ... ALso need to check your Fuel pressure before Winter hits .. it will only get worse ..

As for the oil pressure gauge .. Either put a Mechanical Gauge on it OR check it and possibly change out the Sending unit ..

Kppe posted .. :pca1:

hey john:hellox:

OLAH Trevor .. :hellox:..:rocking:

Yea i do neex to check my fuel pressure and i jus put in a new oil pressure sensor about 2 months ago becausey gauge would drop to 0 driving down the road.. well the new sensor fixed that issue but it still takes about 5 seconds to show oil pressure.. i start my truck and my abs light e brake light and check gauges light come one 5 seconds later all lights go out and oil pressure jumps to 60psi

That sounds normal.. 5 sec is just the sender and the signal all getting to where they need to be .. These trucks are a high Volume oil system .. not high pressure .. so if it takes a min .... thats ok .. 10 second rule though .. and if the oil light dont turn off for 10 sec.. shut it down and stat checkin ..

Ok yea from what quickserve says that as long as the engine is showing oil pressure before 15 seconds its ok.. 15 secs. Is a little long for me but hey they made the spec. not me lol