Leganza Issue... Rough Run off idle, but no codes?

[mclark707]

Hello, new member here. I tried using the search and found a lot of similar problems but I couldn't seem to find the exact one so I decided to sign up and post. I apologize if this had been covered somewhere else.

Here is my issue:

Car starts, warms up, and idles normally. Drives normal for a bit, but then on occasion will be VERY rough from pressing the gas off idle from a stop. I immediately let off the gas and try again until it revs/drives normally. Occasionally it will also with this rough spot in between gears. The weird thing is, there are NO codes showing. I ran my code reader several times to verify that the check engine light wasn't coming on and sure enough, my reader was correct.

Things I have done so far:
Checked spark plugs and plug wires..... no issue
Checked all vacuum lines to and from intake
Cleaned out EGR with brake clean and air
Cleaned out IAC... helped a little, but not much
New O2 (lambda)... no change
Checked air filter.. all clean


Any ideas before I start throwing money at new sensors?

The car is a 2000 Daewoo Leganza 2.2 auto.

Thanks in advance!


~Mike

[benzino]

if cleaning the IAC helped, I would go to the junkyard and try a different one

[Daniel]

Cleaned throttle body both sides of butterfly?
All tiny holes free?