bad idle, missing at wot, loss of power...(long)

[firebirdvert305]

Well ok lemme try and explain to you guys the problem im having. Im running about 19psi(with no boost leaks) on my 1g hacked maf for starters on stock 450's with a walbro 190, e-prom ecu with all the goodies (no fuel cut, no boost cut)...well off to my problems. I have a real bad idle, when the car is warmed up, it seems to get somewhat better, If i shut the car off and come back outside or run into the gas station and restart the car on a "hot" start...the car will idle really rough and want to die. I replaced the biss screw and TB gaskets, helped a little bit but not that much. Sometimes when i stop a redlight and press the clutch in the idle will jump to 1500 then back down to 1000 and do this about 2 times before it stays steady at 1000rpms.I know thats the ecu's way of controlling the ISC, not to idle above 1500. Another problem im experiencing is a miss at wot, it used to happen all the time at about 10psi, well i bought a new pair of accel plug wires and NGKBPR7ES plugs gapped to .026, this helped me out a little but i still get that slight miss/stutter/hesistation at WOT....My car has 143k miles on it, i bought it from the orignal owner who kept it in pretty good shape, im thinking maybe the coilpack or transitor is bad? Could it be MAS overrun? Im running out of ideas...any help will be appreciated.

summary: Flucuating idle on hot start, A very noticeable high rpm miss, and a loss of power in the upper rpms.

 

[underpressure25]

well first off why are you running 19 psi of boost on a stock set of injectors to begin with. Most likely you are detonating because you are not providing enough fuel for your boost level. You can max out a set of 550cc injectors on a 14b turbo, so you should probably turn the boost down around 15 psi max, untill you get bigger injectors and a Apexi SAFC at the least and have it properly tuned by ways of a Wideband o2 or datalogger which is not as good as the wideband. Second a hacked maf always causes all kind of problems at idle and all over the operating range. If you continue torun 19 psi like that you will need at the least a new head gasket soon and maybe a new engine or rebuild soon.
Good luck

 

[firebirdvert305]

Well, when i had 19psi of boost on my 14b and a stock set of 450's...i was seeing 0 count of knock throughout my rpm range and my IDC was at about 94% if i remember correctly.

 

[underpressure25]

Have you tried turning down the boost to stock level and making a run? Do this and see if the problem persists. But yeah I'm just saying its a bad idea to run 19 psi with out fuel upgrades. Plus at 19 psi your 14b wont last long because you are over working it. Also check your plugs again to if they tell you anything.

 

[willthiswork]

... the 14b is only safely rated to 14-15psi.

If you plan on running 19psi like that, I'd suggest upgrading to a 16g before you toast that one.