Jeep Wrangler 1990 — technical service bulletin
Bulletin RCL/589 · NHTSA communication 37980 · issued Nov 1, 1994
Technical service bulletin
communication type
Engine and Engine Cooling
component
1990
model years
1
vehicle entries
Official summary
Hydrocarbon and carbon monoxide emissions levls for the above listed model vehicles may exceed the limits allowed by california emissions standards. To correct the condition, the pcv harness, choke vacuum diaphragm, egr valve and decel valve, if equipped, must be replaced. *tw
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.