Check engine light on 98 Trooper

About 18 months ago, my check engine light on my 98 Isuzu Trooper (206,000 miles) came on. I kept driving it mainly because I didn’t want to pay the mechanic’s charge to plug it into the diagnostic thingamajig. Well, I must have fixed it, because it finally went out, stayed out. Any ideas? EGR valve replaced a few thousand miles ago. Don’t drive it much now - it’s a fishing/hunting transportation.

Maybe the light bulb burned out.

Why are you asking about this now? It wasn’t important 18 months ago when the light came on.

Troopers with over 200K miles don’t magically repair themselves. Whatever caused the light to come on is still not working correctly.

Some possibilities:

  1. Error detection of evaporative emissions control systems is notoriously flaky. If the light was only on for a few weeks, it might have been a loose gas cap or similar problem. Loose gas caps are one of the many conditions that most computers will clear out eventually if they are not seen for some X number of starts. X varies from car to car.

  2. A few older cars – especially some 1995, 1996 and 1997 models when On Board Diagnostics were brand new simply turn on check engine lights once in a great while at random due to programming bugs. 1998 seems a bit late for that. … But maybe.

As Mcparadise suggests, the Check Engine Light bulb could be burned out. Does it come on briefly when you first start the car? It probably should.

Thanks for taking the time to reply. In response to your chiding me for not worrying sooner, I did take it to the only shop in the small town where it’s garaged who said he had some knowledge of Troopers. Well, he didn’t. So, I have kept driving it, thinking or hoping it was some vacuum leak. It may well be. Next time I drive it this spring, I’ll get it to a dealership 150 miles away.

There are auto parts stores closer than 150 miles. Many of the chain parts stores will do the scans for free (at no cost), or, lend the scan tool for the customer to do so. Any garage can do the scan. Get the scan, and bring the code (ex. P0333, etc) here for cussin’ and discussin’.

There is nothing magical about a Trooper where one needs some kind specialized insider knowledge. It is true that there are sometimes some particular quirks and/or common problems that might be associated with a make, but most any decent mechanic should be able to handle this as well as a dealer (and for less too). This is especially the case with the check engine light thing which is a standard OBD-2 system - same on the Trooper as on anything else (though there are a small number of make specific codes).

As hellokit noted below - auto parts chain stores will read these codes for free. And then you can post them here. I’m also in the category of people who are curious as to whether the light was actually cleared by the computer or the bulb burned.

Thank you for taking the time to reply with meaningful information. There’s a NAPA in town. Never knew this that they can do a scan for free. Thanks again.

Call them first to ask. I’ve never tried NAPA but have gotten this at both Autozone and Advance.

The light, if it’s not burned out, will come on when you turn on the key. ALL of the warning lights will…After you start the engine, in a few seconds, they should all go off…If your CEL NEVER comes on, the first step would be to replace the bulb…What happens now?? If it’s on, as others have posted, most parts stores will read the codes for you…THEN you can decide if it’s something you need to fix or not…

That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.

Just returned from down south and have the Trooper up north here. Soon as I find out about the CEL, I’ll send a reply. Thanks for your input.

I have yet had no time to find a diagnostic for free - shops up here all charge a bunch, but I haven’t checked AutoZone or Advanced Auto parts. Soon as I learn something, I’ll send a reply. Thanks for the message.

Thanks for taking time to send a message. As soon as I learn what’s going on, I’ll post it.

Thank you for the good idea about seeing if the CEL comes on with the rest. Just returned north here from Florida, so haven’t had chance to get it to computer diagnostic thingamajig. Will post it when I find out. Thanks again.

Thank you Joseph for the suggestions about Autozone and Advanced Auto Parts. Also for the good metaphor (I was a teacher). The light’s been waving its hand for quite a while. I’ll post something when I find out. Thanks for taking the time to send the message.