HI everyone.
like stated the car is a 97 lx f22b2. When the car is cold started it runs like a champ, you can take it through the rpm band with no issues. when the car reaches operating temperature it will idle fine until revved to any rpm , at which point it can't catch itself and stalls out. The car won't start unless you feather the gas and won't idle ( just shuts off). So what exactly could my issue be. I've replaced head gasket,intake mani gasket, new dizzy, plugs ,wires, ignition coil, seals(i.e. cam seals vc gasket), timing belt and balance belt changed, timing is dead on. I've checked grounds and vacuum lines and everything is in good order. I've also cleaned the iacv but the problem persists. no cels in the car. Any insite would be greatly appreciated.

 

Does the throttle position sensor read what it should?

 

yes the tps reads in the ranges that are acceptable according to alldata.

 

Check your Fast Idle Air Valve and your IACV (Idle Air Control Valve).

Also, consider checking the EGR or cleaning out the EGR ports.

 

I've cleaned the egr ports and checked the erg all seem good. I've also cleaned iacv, and checked all the lines that run to it. fast idle thermal valve is one I haven't checked.

 

When was the last time the oxygen sensor was replaced ? It's possible the icm is bad and after it heats up it starts cutting out.

 

the one on the exhaust manifold looks fairly new. the other on the exhaust itself may be older but I don't have codes for them .

 

I would probably take a look inside the ecu and look for any burned spots. If that checked out ok, I would grab another icm from the junkyard.

 

that's the only thing I haven't done yet. I have it ready to take off just never opened it up.

 

I have picked up two ecu both work car runs fine until it's warm and revved. it still stumbles and won't start up afterwards . it only will stall after its revved over 3k anything under that the car is fine.

 

Verify base timing is correctly set and the IAC is functional.
At lower rpm changes the dashpot settings do not need to change as drastically.
From a higher rpm the IAC will remain closed to allow for a pre-programed reduction of rpm, when rpm reaches closer to idle the dashpot will open(or open more) to allow for a smooth transition to idle. Otherwise the engine will rev down past idle and stall.
If the IAC is sticking or slow to react to the higher rpm change the engine will stall.
Verify the voltage to the valve. When the engine is cold the FITV(Fast Idle Thermo Valve) will prevent the engine from stalling as it acts as a secondary IAC when active and the PCM will be in a cold start condition with changes to timing and fuel. With the engine warmed up FITV will no longer be functional(closed) and the IACV should be the means by which the PCM controls idle.

If when warm with all accessories on the engine struggles to maintain idle this would point to an IAC or timing issue.

Verify all wiring is undamaged, unbroken and not missing.