2003 ranger 3.0 v6 flashing engine light once youhit highway speed of 65 to 70 it boggs down chugs have replaced plugs wires coil pack cleaned mass air flow sensor. what else do i need to do?
Country: United StatesMake: FordModel: Ranger 4x2Year: 2003Engine: 3.0
Hi, I’m Chris. Welcome and thanks for asking your question!
Have you narrowed it down to just one or two cylinders causing this?
Is it always this cylinder(s) or is the concern moving around to random cylinders?
sometimes code is #4 sometimes #6 sometimes just cyl misfire system to lean those are the three codes. it runs fine unless you hit 65 mph then the problem starts
Have you ran a cylinder compression and leak down test on every cylinder?
Have you done anything to address the lean codes?
One common issue on this engine is the valve seats getting crushed and flattened out and causing the compression to a be a little lower resulting in a misfire under certain loads. The cylinder compression and leak down test will tell you if that head needs to be replaced.
You then need to check and see if the source of the misfire is the lean codes. Low fuel pressure from a clogged filter or weak pump can cause both concerns. leaking intake gaskets or PCV or vacuum hoses can cause both concerns.
I myself do not work for Just Answer/Pearl. I am a certified tech and my background experience has been verified by this company so that I can answer questions here. I work for YOU, the customer. This is what I do to pay my bills, it is my job. I really do appreciate you coming here and asking a question. I also appreciate all the details you have provided. Do understand helping someone through a keyboard is tough. Also my skill level may not match yours and I may have described a task to do, thats beyond your abilities. In that case just reply. Please rate my answer with one of the higher 3 levels so I get credited for helping you. I would prefer not to get a lower rating which results in a negative on my record. Please rate my answer, not the website, or the bad news if there is bad news. If you need to reply for clarification, before or after rating please do so.
16 years experience with Ford.