I have a 1993 loyale with 140,000 mile on it . when I'm driving at freeway speeds I hear a click then my car surges or it clicks then it slows down. Its just a little bit but enough to annoy me. Also I did a leak down test and I know the I have a crack head. and this is why my car idles rough. I was wondering if anyone had a set of heads laying around they want to sell. Thanks

 

astro360

Sounds like the air conditioning cycling on and off. You DO know that the AC comes on when you've got the controls set to Defrost?

Yep, A/C cycle is my guess too (if A/C or defrost are on), try running with controls OFF, or temporally unplug the A/C fuse and see if it goes away.

 

Gary

Yup thats what mine does when the AC cycles..thats why I never run it ..or I only use the defrost long enough to clear the windows. Mine idles a little rough cause of the EGR being bad..one of these days I will replace it.