I need somehelp

I have a de and when i turn on the car it turns on and tries too die out i can press the throttle to keep it on but once i let go it slowly goes down in rpm and i unplugged the maf it turns on goes to 2k rpm after 30 seconds it dies i already changed maf, crankshaft and camshaft sensors. Also i changed the fuel pump and injectors.i looked at all the fuses and all of them are good and no codes thrown

icer5160

iTrader: (4)

So many things could cause behavior like this. Have you scanned the vehicle for codes? Are there aftermarket mods? What year and trim level?
-Icer

I need somehelp

Yeah i checked for codes nothing pops up just a plenum spacer and test pipes its a 03 touring

icer5160

iTrader: (4)

You have the downstream O2 sensors connected & installed on the test Pipes? You really need a tune if you're running test pipes, otherwise the ECM will change AFR and timing in a negative way.

Without any codes to go off of, you're going to need access to a scan tool that can view live data and do advanced diagnostics. If a plenum spacer was installed, I would check for any vacuum leaks.

Also, if you replaced maf/cam/crank sensors, did you use OEM or some local parts brand? Always use OEM for major engine sensors on these vehicles. You're probably ok with the fuel pump, not sure about the injectors.

Always try to test and verify the problem before firing the parts canon.

Cheers!
-Icer