[darrensavoye]

I have a '98 4Runner with 180,000 miles that has never ginen me any problems until last week. I was out of town for a week and the truck was not run. For teh past few days she's been running very rough, primarily when idling, she'll bounce from 800 rpms up to 1200 rpms and when you accelerate she'll miss. The CHECK engine light comes on as well. My first guess was bad gas, moisture in the tank or possibly a vacuum leak. All the vacuum lines are in good shape and she has a fresh tank of gas. The problem appeared to correct itself and she was running fine for a few days but it's acting up again.

Any suggestions on what the problem may be?

 

[85sfarunner]

Check engine light means your getting error codes from the ECU. I think some auto parts stores (Autozone, etc..) can read your codes for free. The codes will point you in the right direction and you can go from there.

 

[darrensavoye]

Thanks, I'll check with autozone and see what develops.

 

[98 Taco]

where are you located?
good luck!!
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I am looking at a 4-runner 1996-2000