Rough idle and acceleration HELP

[Mzarlenga]

Well the truck always had a rough idle for about 2 or 3 seconds when starting up, then would smooth out and run great. Yesterday, it randomly started running really rough like it did for the 2 or 3 seconds at startup, and when it accelerates it sounds like crap its really wierd. It sounds almost rattly and dry when accelerating. The only thing that I messed with between the time of it running like normal to now is the switch (I think its called the vacuum pump) on the fuel bowl because I'm in the middle of fixing a small fuel leak in the valley beneath the fuel bowl. I just checked to see if there was any more fuel accumulating, and there wasn't. Then I noticed the switch and turned it, and I heard fluid moving inside the fuel bowl or the tubes connecting to the fuel bowl, so I shut it off. I really have no idea what that did or if it could have affected the engine running. I had a friend over yesterday who suggested to add more oil since it was a few quarts low and it sounded like it was running dry. So we added more, and there was no difference. It was 15-40 oil by the way. If anyone has any idea what could be causing this please help me out! Thanks in advance,

Mike

[Patrick Feeley]

Check the wiring to the Injection Pressure Regulator (IPR) valve (back of the High Pressure Oil Pump or HPOP which is in the engine valley in front of the filter bowl). This wiring is part of the fuel bowl wiring harness and leaking fuel can wreak havok with the wiring insulation causing all kinds of problems. Also, make sure the "tin nut" that holds the regulator solenoid on the IPR body is there and tight. Cheers!

[madpogue]

The oil being that low, gotta ask, how old is it?

[southend]

Originally Posted by madpogue

The oil being that low, gotta ask, how old is it?

Exactly what I was thinking, you were draining the fuel bowl with the yellow lever. Change your oil, these trucks must have good oil in them.

Sent from my SCH-I500

[Mzarlenga]

To be honest I have no clue. I've had it for about two weeks and I'm planning on doing an oil change today because my neighbor gave me a ton of 15-40 oil from his firehouse, but I was wondering what drainin the fuel bowl does. Do you have to drain it when you change the filter? And is there a tube you have to disconnect or something to drain it?

[southend]

Originally Posted by Mzarlenga

To be honest I have no clue. I've had it for about two weeks and I'm planning on doing an oil change today because my neighbor gave me a ton of 15-40 oil from his firehouse, but I was wondering what drainin the fuel bowl does. Do you have to drain it when you change the filter? And is there a tube you have to disconnect or something to drain it?

draining the fuel bowl periodically lets the water out, it has a tube connected to it that lets it drain all over your front end and the ground. Get that oil changed, with diesel engine oil.

Sent from my SCH-I500

[Chop]

[QUOTE=Mzarlenga;3100507] my neighbor gave me a ton of 15-40 oil from his firehouse,

Wow ,how did your neighbor get free oil ? I always have to pay for it .I do know as a taxpayer we all pay dearly for these firefighters and others who " serve " us , Is he giving you used oil ?

[BigFuel]

Originally Posted by Mzarlenga

Do you have to drain it when you change the filter? And is there a tube you have to disconnect or something to drain it?

You do need to drain it with a fuel filter swap because if you do not the unfiltered fuel will mix with the filtered fuel when you remove the filter from bowl. Not disastrous but our fuel injectors need to stay as clean as possible on the inside to minimize wear from foreign objects such as hard particles and water.

Personally I do not use the yellow dump valve as it only lets go of the fuel in the bowl and the older the truck the more likely it'll develop a fuel leak from the worn o-rings that support the valve. I open the bowls cap and use a suction canister attached to air pressure to vacuum out all the fluid and the crap that stays on the bottom. I do this every February depending on the miles I've rolled on or the lack of faith in the fuel station to change their filters. Your truck will run "rough" for a while, 10-30 miles, till it gets all of the air out of it's system