Hello, on my 88 w100 I have codes for the temp sensor, tps, and iac. All have been replaced. There are no vaccum leaks. The engine surges at idle when warm. Also I have to give it gas gradually, it I floor it , it stalls out. Anyone know what this could be? Or where to look first

 

Did you clear the codes after you replaced the parts? The IAC needs to be adjusted you cant just throw it on and done. Was the fuel filter ever replaced? You need to check and see what kind of fuel pressure you have also.