I have a 1990 suburban 5.7 tbi is puring fuel constantly flooding the engine will run but barley I have changed o2 sensor map throttle body borrowed from a good running truck cap rotor temp sensor idle control IAC motor ignition module borrowed an ecm from another truck still flooding no codes dies when timing wire is pulled and wont set a code for that

The TBI unit is going to be the route of your problem. Clean and inspect the insides of the unit. Next to the injector is the fuel pressure regulator. Either the injector pressure regulator has failed and is leaking, the o-ring that seals the regulator to the TBI has failed, or because of age and time. The housing itself has oxidized or cracked and is letting fuel leak into the throttle body. There are many different ways that the TBI unit can fail. An unmetered amount of air getting into the engine, low or no fuel pressure, or throttle linkage was sticking or broken, then there would be other symptoms. You provided a great description and list of symptoms. Please, when you have time, take a closer look at the TBI unit and let me know. If you have any other questions please write back and I'll do my best, good luck.

By "throttle body carb" I am assuming you to mean that the engine is equipped with Throttle Body Injection (TBI). The O2 sensors on that engine do not even start working for about 5 minutes. They are not going to cause a problem on start-up. A fuel filter will most likely not cause a problem on start-up or idle either. A fuel filter is most likely to cause problems on acceleration or when pulling a hill. A more likely cause would be a n Engine Coolant Temperature (ECT) sensor. If one of these is reading too low, it will cause the engine to flood and smoke black out the exhaust - especially on start-up. (LIke a choke sticking on an old carbureted engine.) If your truck is equipped with a gauge, there may be 2 Coolant sensors. One for the gauge and one for the computer. If you replace it, make sure you are replacing the sensor for the computer.

I think your truck has throttle body fuel delivery? My understanding is a temp sensor tells either computer or throttle body that engine is warm and cuts out "choke". Hope this can help you.

From your description it sounds like your ECU is believing you are at Wide Open Throttle (WOT) when conditions are to the contrary.

MAP sensor is a good place to start, but their failure rate is seldom, Id be more apt to look at the Throttle Position Sensor (TPS), and while you are at it take a look at the throttle stop and AIS motor/sensor too.

When you open and close the throttle from the throttle body is there hesitation, does it open/close all the way, etc? If you answered "yes" to any of those, look at your throttle stop and kick down (if automatic)

I'd Check the injector too while I'm at it. Does it pulse constantly? There may be a ground issue. or a problem with the ECU.

Another place to look: On the smaller engines with TBIs the male connector cable likes to rock in out of the receptacle. make sure it's tight.

Hope this helps

relace the throtle air idle valve.The temp switch will allso cause this problem.

Check the trottle body postioning sensor...

you have to reset base idle see manual at library for procedure

That eliminates the crankshaft and camshaft position sensors. Have you checked the fuel injector itself for an open winding or stuck valve plunger? There should not be a steady 12 volts to the injector--if good injector, it would be spraying fuel steadily into the throttle body. But at least the engine should try to run if poorly. Take the injector out, dry it off with air, and intermittently apply 12 volts to one terminal while grounding the other. You should hear a click from inside every time you touch 12 volts. If not, replace it. If it does, it may be plugged with debris. Try blowing through it in reverse with compressed air.

Did you re check for new codes after o2 replacement? Does the idle hunt (up and down)? Have someone check the EGR valve.

It sounds like you may have a bad fuel pressure regulator. The fuel pressure regulator is in the throttle body housing and the throttle body in your truck works best at 13psi to 15psi, Any other setting will cause problems. Check the vacuum hose to the fuel pressure regulator at the throttle body and check the fuel pressure at the shredder valve. The way the throttle body works is for the first 75% of the throttle, the ecm uses the signal form the O2 sensors to control the air fuel ratio and tries to keep it to 14.7:1 but at full throttle it by pass the O2 sensor signal and runs the engine richer and advances the timing so you can drive with wings like red bull. The Map sensor then takes over to promote the engine to run richer so you don't run lean and detonation occurs. If there is a problem with your throttle body position sensor, map sensor. and fuel pressure regulator, then at WOT (skinny peddle down) you may be running to rich. The other thing to is if your fuel pressure drops at WOT you'll get a lean condition and then you'll have detonation ( Knocking) and the timing will be turned down to keep detonation from occurring again and that may be the cause if your check engine light too. First and easiest thing to do is change the fuel filter and add fuel injector cleaner to you gas tank, buy a throttle body cleaner and clean your throttle body to make sure you don't have varnish build up around the throttle body, just follow the instruction on the can. Throttle body cleaner not carb cleaner. Start with that and i hope we don't have to do any more to get your truck running like a rocket. Good luck and keep me posted. Be glad to help.