problem with rpm range

[phillipm]

I have a 1999 for expidition with a superchip, flowmaster exhaust and just recently got a engine flush. About a month back i noticed, when i puched it the rpms would only go up to about 3300 and before they had been passing 4000 easy. I don't think i need a tune up and i don't know what the problem is. help!!

[rivguy]

do you have any other symptoms like high rpm cut-out, popping, loss of power at high rpm?

[phillipm]

I noticed i can get to high rpms when im moving at about 40 miles an hour sometimes. But i can never get to a high rpm at a dead stop. My truck used to be able to jump to 4000rpms or high right off the start. I wonder if a bad alternator has anything to do with it.

[phillipm]

Re: problem with rpm range
I noticed i can get to high rpms when im moving at about 40 miles an hour sometimes. But i can never get to a high rpm at a dead stop. My truck used to be able to jump to 4000rpms or high right off the start. I wonder if a bad alternator has anything to do with it.

[rivguy]

has the fuel filter ever been replaced - have seen many of these trucks plug filters and engine will run at lower rpm ranges but looses power at high rpm. easy to test if you have a pressure gage or pull the filter off and shake it and see if dirt comes out.

[phillipm]

yeah i replaced my fuel filter like 3months ago. The problem isn't a loss of power at a high rpm. The problem is i can't get to a high rpm as quick as i used to. It doesn't jump to a high rpm as quick as it used to. The rpms gradually get up there but it takes a while. But before it was like a quick boost.

[bearcat329]

i have a 97 with the superchips and a flowmaster as well, what is the computer set to by way of the superchips programmer? right now mine's set for 92 octane, towing /hauling, with the trans shift points and shift pressure bumped up 3 clicks on all shifts
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