1998 GMC Sonoma Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 1998 GMC Sonoma
Verified by mechanics, reported by drivers like you
Ask a mechanic in our community
Never overpay. Check prices with our estimator
Our experts translate recalls into plain English
1998 GMC Sonoma ProblemsCheck Engine Light With Code P1870
Vehicles equipped whit a 4 speed automatic transmission may develop a harsh 1-2 shift and/or illumination of the Check Engine Light with code P1870 stored. This can be caused by wear of the bore for the TCC isolator and regulator valves in the valve body. This condition does not commonly occur until the transmission reaches normal operating temperature. If the valve body is worn, replacement will be necessary to correct this concern.
A Loose or worn gas cap may cause Check Engine Light to illuminate.
The serpentine belt tensioner can fail; it may become noisy and/or the belt may jump off. Replacement of the failed tensioner will be necessary.