5.4L rough idle
#1
5.4L rough idle
I had a rough idle problem. Pulled codes at Autozone which were MAF and all 4 (right and left bank) O2 sensors. Turns out it was the VACUUM ELBOW on back of the EGR, the one leading from the PCV valve. Rotted/melted! Felt around and soon as I covered the hole with my finger the engine smoothed right out. Hope this helps.