1998 Chevrolet Express Van Owner's Manual - Page 250

If your vehicle has a 7.4 liter engine and air conditioning, your vehicle will have aauxiliary engine fanin addition to the belt driven fan. Before closing the hood, be sure all the filler caps are on properly. Then lift the hood torelieve pressure on the hood prop. Remove the hoodprop from the slot in the hoodand return the prop to its retainer. Then just let the hood down and close it firmly. Tampering With Noise Control System Prohibited Federal law prohibits the followingacts or the causing thereof Noise Control System The following information relates to compliance with Federal noise emission standards for vehicles with a Gross Vehicle Weight Rating (GVWR) of more than 10,000 lbs. (4 536 kg). The Maintenance Schedule provides information on maintaining the noise control system to minimize degradation of the noiseemission control system during the life of your vehicle. The noise control system warranty is given in your Warranty booklet. These standards apply only to vehicles sold in the United States. 1 . The removal or rendering inoperative by anyperson, other than for purposes of maintenance, repair or replacement, of any device or element of design incorporated into any new vehicle for the purpose of noise control, prior to its sale or delivery to the ultimate purchaser or while it is in use; or 2. The use of the vehicle after suchdevice or element of design has been removed rendered inoperative or by any person. Among those acts presumed to constitute tampering are the acts listed below. Insulation: Removal of the noise shields or underhood insulation. Engine: Removal or rendering engine speed governor (if equipped) inoperative so as to allow engine speed to exceed manufacturer specifications.