ok my 5.2 is throwing a code of optimum idle not reached which is true it idles at about a grand when its warm and when the a/c is off it idles even higher does anyone know what could cause this i replaced the iac thinking that was it but no the only thing i can think of is the pcm and when the engine is cold it idles at about 650 where i like it could it be the engine tring to warm up because i put a 180 tstat in any input would be nice

 

The 180 T-stat CAN set this code, because the PCM thinks operating temp should be 195.

What code is it setting (the number)?

 

as i remember p1296 i looked in my factory manual and it said that idle was not reached which is true it idles high

 

The description of the code that comes up for me is: No 5 Volts to MAP Sensor - Loss of 5 volt feed to the MAP Sensor has been detected for code p1296

 

i know its has to do with idle not being reached i just forget the number i did the key cycle and went to autozone and used the scaner and it was the same both times in the book it says target idle not reach actual idle is not target idle it is p1294 i looked

 

Check your vacuum. You might have a leak somewhere. (should be around 19/20)

Also, check the IAC voltage. You could have a problem somewhere in the wiring.

Last thing to check would be the throttle plate and/or linkage. Make sure everything is good there.

 

alright thanks man i let you know if i find whats wrong

 

What fixed this?

 

i havent got around to fixing the problem yet