ok i just finished my auto to manual tranny swap a couple weeks ago and the car jumped up to high idle at startup around 2200 - 3000, then when it settles back down after a minute of two while it sits its ok then when i drive it and stop the rpm's drop all the way down to 500 or less and cuts out on me alot. my engine it boosted with turbo and before i did the swap i had a code for the tps, but code is gone now could it be a bad tps, or what could it be? im gonna be putting on a fr head and 9.0.1 compression forged diamond pistons and eagle rods and 50 lbs injectors so if its something that will mess up engine after i do thi upgrade i wanna get it taken care of.any insight.

i would look into the tps sensor, when i replaced my tb i messed up my tps and it caused it to idle very high and then would drop down low. so sounds like it could be the culrip here.

My guess would be vac leak

What codes did it show

Tom

Yep, I double what Tom said on this one.

ill double check all my vac lines but i ordered a tps , cause i had that code coming up before like something was wrong with it so. but when i go home later this week ill check it all out.

there is no vac leak that i found, i ordered a tps to see if that fixes it. the code that i had before was for low voltage. if the tps doesn't fix it what else could it be keep in mind i just finished a auot to manual swap so could it be somwthing with the comp. would i need the car retuned?

i put in the new tps and started it up it still seems to jump up a little at startup but doesnt seem to idle down as low sticks around 500-750 rpms i didnt get a chance to drive it cause of the snow but hopefully its ok.