1988 Other Mitsubishi Models High erratic idle and coolant r

1988 MITSUBISHI
184,000 MILES • 4 CYL • 4WD • MANUAL
Avatar
SCOCARL21
  • MEMBER
  • 1 POST
I have a 1988 Mitsubishi Mighty Max 4wd. It idles between 1650 and 1800 rpms, it never stays at one speed. The temp gauge always shows that it is overheating and today the coolant overflow reservoir was boiling over. I just got the truck and I have no idea what is wrong. It also doesn't have much power at all. It will barely let me rev to 3200 rpms when I am driving. Can you help me out with this?
Dec 8, 2008 at 10:49 AM
Advertisement
Avatar
KHLOW2008
  • CERTIFIED EXPERT
  • 41,814 POSTS
Hi scocarl21,

Thank you for the donation.

Let us start with the idling. High idling speed is either due to
1. Improper idling adjustment. Check the Idle speed adjust screw.
2. Idle Speed Control (ISC). Check if the ISC is faulty. Insufficient coolant can cause it to malfunction as well.

Lack of power and improper idling speed could be related. I would suggest checking the ignition timiing.

Overheating.
What type of cooling fan is your vehicle equipped with? Electrical or mechanical with cluth?

Are there any coolant losses? Check the radiator coolant level at cold engine. Are the radiator cap seals in good condition? A bad radiator cap would allow coolant to be pushed out to the reserve tank when the coolant heats up.
Dec 9, 2008 at 4:05 PM