I recently purchased a 97 jeep Wrangler, 2.5, auto transmission,a/c, 133000 miles. I am having a problem with my engine idling rough and sputtering when the engine is cold.
I took it to a mechanic who used a snap-on scanner to diagnose my problem. There where no CEL codes. Everything looked fine. All the sensors appeared to be reading correctly. The only problem he noticed was that when the jeep was started cold, the scanner had a low engine vacuum reading of about 11. After the engine started warming up, the vacuum picked up close to normal and the engine idles much better. Still a little rough but better. He checked the engine for vacuum leaks and said that he could not find any. He claims to have checked it very well.
After his diagnose? he suggested that it was probably an internal engine problem and that I should just put a new engine in it. I'm not sure that I am buying this. Has anyone had an issue similar to this? Can anyone point me in the right direction? Please help.