Hi folks,
I have a 92 Trooper LS with the 3.2 DOHC engine. It has been a wonderfully reliable and comfortable vehicle for me these past 160k miles.
About 2 months ago, the check engine light started coming on sporadically, mainly while driving at highway speed in cold weather. It would usually go off once the vehicle slowed down to about 30 mph from 50 mph. This has continued and seems to be even more random these days - i.e. it will come on for about 2 minutes while driving 30 mph and then go off. I've had it in the shop 2x and the computer cannot find any codes to accompany this. Mechanic tells me that I need to bring it in while the light is still on, otherwise they cannot trace it. But the light does not stay on for me.
Simultaneously, the speedometer has been acting really wacky. I'll be driving 70 mph and suddenly I'll look down and it is sitting at zero. Then it will jump up and dip up and down crazily before finally settling back to normal. This sometimes happens in unison with the check engine light, but I also see the speedometer glitches more often than the check engine light.
I'm not noticing any other problems, so I've been just living with it. Has anyone seen these symptoms and know what the problem is? Do I need to get it fixed or is it ok to just let it be, considering the age and high mileage of the Trooper?
Thanks, Eric