p0174 code cel sometimes flashes csvt plz help

[pdq99csvt]

I have a 99 csvt and I have a p0174 system to lean bank two been trying to spray carb cleaner around everything but cant seem to find a leak but I can hear a hiss by the egr ish area car has rough idle sometimes and Cel flashing sometimes when taking off in low rpms and sometimes at idle car has new tb that is bored out ( thanks Malcolm) and new mustang 195 lph fuel pump please help if u need more info let me know thanks

Thanks for the forum being back up to :drool:

 

[BrApple]

flashing cel is a miss-fire.

might be time for an O2 sensor.

 

[pdq99csvt]

I replaced 02 sensor 5 months ago and I think I would get a 02 sensor code not just lean mixture ....?

 

[beyondloadedSE]

How miles are on the car? Have the intake manifold gaskets ever been replaced?

 

[pdq99csvt]

181000 miles looking to put a 3 l in it soon but I need it to pass echeck soon how do I figure out if it is the gaskets

 

[beyondloadedSE]

181000 miles looking to put a 3 l in it soon but I need it to pass echeck soon how do I figure out if it is the gaskets

Unfortunately it's going to very tough to diagnose if it's the gaskets, especially if it's the LIM gaskets which probably can't be checked at all unless you disassemble the UIM and LIM. Once you take them off it's probably best to replace them anyways. I would guess the heat has probably gotten the best of them and they are pretty shriveled up. Mine were pretty bad on my 96 after 100k miles or so. From what I recall both gasket sets are around $25/each.