Running Problem
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New User
Joined: Jul 2005
Posts: 9
Likes: 0
Running Problem
I have been having a ongoing running issue. 94 460 sd, in RV.
Hard to start, but idles fine once its cranks. Spits and pops at take off but you can pump the gas and it will get though it and then will run fine until you stop and take off again.
Replaced plugs, wires, cap and rotor, coil, fuel filter. I have been told it could be a weak fuel pump, but it seems unlikley that it would run so well on the interstate and up large inclines with a weak pump.(this problem has been on going for over a year)
I am wondering if it could be vacuum related. The units has a vac guage and I noticed when the engine starting missing and popping the vac guage goes into the negative. Something else i noticed is that when the guage maxes out and goes into the negative for a substaned time, the ac vents are effected.
Does anyone have any thoughts on what I can check?
Hard to start, but idles fine once its cranks. Spits and pops at take off but you can pump the gas and it will get though it and then will run fine until you stop and take off again.
Replaced plugs, wires, cap and rotor, coil, fuel filter. I have been told it could be a weak fuel pump, but it seems unlikley that it would run so well on the interstate and up large inclines with a weak pump.(this problem has been on going for over a year)
I am wondering if it could be vacuum related. The units has a vac guage and I noticed when the engine starting missing and popping the vac guage goes into the negative. Something else i noticed is that when the guage maxes out and goes into the negative for a substaned time, the ac vents are effected.
Does anyone have any thoughts on what I can check?
Lead Driver
Joined: May 2003
Posts: 9,303
Likes: 48
From: Lyndonville, Vermont
Well let me see!! Popping of any kind in the intake usually means a lean condition. Such as fuel pump or filter. Hard start Could be the same but my guess its not either of those esp if you can take it down the road and floor it and it pulls hard.
I would check map sensor coolant temp sensor for proper value's. Does it have a Maf device? Then that also. How many miles on this thing? Is the timing chain ready to take a hike? I would put a fuel pressure gauge on it to be sure. There's a regulator in there also.
Dick
I would check map sensor coolant temp sensor for proper value's. Does it have a Maf device? Then that also. How many miles on this thing? Is the timing chain ready to take a hike? I would put a fuel pressure gauge on it to be sure. There's a regulator in there also.
Dick
