l have th 6.5 turbo my idle is almost flat when warm how can l bring it up

? My idle is flat? What are you asking? Also Please fill out a Signature, So we all know what you got, to best help us, help you.

94 1500 gmc clubcab 4x4 just seems like idle is to low when it is warm tac is just above the first line when l first start it it is 3lines up

94 1500 gmc clubcab 4x4 just seems like idle is to low when it is warm tac is just above the first line when l first start it it is 3lines up

You're good to go.

The first line on the tach is 500 RPM, PCM controls idle, somewhere around ~600, so one line above 500 is spot on.

When engine coolant is cold, PCM recieves this information from the coolant temp sensor in the crossover between the heads, and increases idle speed and injection timing, that's where you see it about 3 lines above, maybe as high as ~900 RPM for a time.

l sorry l meant it just sits on the bottom of tac when warm or is the very first line on the tac 500

l sorry l meant it just sits on the bottom of tac when warm or is the very first line on the tac 500

Yes, the very first line on the tach is 500, that's where mine sits at warm idle too.

The needle is fat, the line is fat, the gauges are only somewhat accurate, mine idles at ~585 RPM on the tech 1, you would have to verify the actual idle speed with a scanner of some sort to know if you actually had a concern.

Mine idles around 550. Anything around 500-600 is normal.