Silverado Idling problems
I inherited a 2000 Silverado with a vortec 6 litre. Before receiving it, the exhaust was re-done and cats removed. The check engine system was disabled and cannot be read.
When the truck is cold and in gear, the idle jumps up and down, and will eventually die. The idle is fine in park or neutral. If I am in gear and driving I have no issues, and once it is warmed up I have no issues. the only time it presents itself is if it is cold, I am in gear and idle.
I thought I would get lucky by just replacing the likely culprits. I replaced the IAC valve and TPS sensor. I inspected and cleaned the MAF and EGR. Both looked fine. I also cleaned out the throttle body and intake the best I could with berrymans and seafoam.
I am a novice and will probably have to take it to a shop and have the check engine fixed and diagnosed.
Any suggestions would be appreciated!