Underhood, Top Cover/Trim Pad & Instrument Cluster Area Information

Underhood 23-19-20-00

1. Engine compartment components are a major source of instrument panel noise. Most are induced by a specific rpm. (If noise is not reproduced by accelerating the engine, go to Step 2.) These noises are caused by contact to a vibrating component. Some known problems are: fuel lines, brake lines, H-valves, wiring, A/C hoses, and components and/or shift cables touching sheetmetal or underhood components. (For possible shift cable noise, refer to "Panel Center" section.) Pulling these items away will eliminate the noise. Verify you are correct by letting the item make contact again. Isolate permanently with foam tape, tie strips, or by bending the item to obtain clearance.

2. Some problems are induced by road vibrations. A quick way to find some of these problems is to flex or press on body components, checking for loose or missing screws. Some noises you can find in this way are: loose fenders, headlamp bezels, hood hinges and stabilizers, cowl screens, and washer bottles. Tightening screws or isolating the loose items with foam tape will repair the deficiency.

Some underhood problems can only be reproduced by driving the vehicle. The most often heard underhood problem is speedometer cable noise. This noise is usually most apparent at speeds under 45 mph as a constant ticking or rumbling sound. (For suspected speedometer cable noise refer to "Cluster" section 23-19-80.) Loose hoods, fenders, etc. may only make noise when driving the vehicle. Rough road conditions are usually the best at helping to locate these. Listen closely to determine area of failure. Check the area for rub or wear marks or chipped paint. Bend or move parts to obtain clearance.

Top Cover/Trim Pad Area 23-19-60-00

1. Accelerate engine until noise appears. Lightly touch cover in different places to eliminate noise. (If you are unable to reproduce noise go to Step 2.) Tighten all cover/pad mounting screws and see if problem is repaired. If not, pull cover and check to see if noise is still present. If it is gone, add foam to the place you touched to silence noise and verify. Touch wiring clips, harnesses, and ducting to eliminate noise. Isolate with foam or tape wiring as required. Check for loose panel mounts or panel mounted speakers.

2. Tighten all cover/pad mounting screws. Road test vehicle and listen for squeaks and rattles. Some noises are caused by contact to the windshield and A-pillars. Add foam, reposition cover or trim moldings to obtain clearance. Other noises will be caused by loose panel mounts or panel speakers. If you are unable to find or fix noise, go to the "Underhood" or "Panel Center" sections.

Instrument Cluster Area 23-19-80-00

1. The most common cluster area noise is the speedometer cable. (For non-speedometer cable noise go to Step 2.) Most speedometer cable noise is caused by improper routing in the engine compartment. Be sure to eliminate contact with the diverter hose, shift cable (auto), and the air cleaner. If routing is correct, eliminate tight bends in the cable. If no problem is found, pull the speedometer cable core and lubricate.
2. Accelerate engine to reproduce noise. Lightly touch cluster bezel to eliminate noise. (If noise is not eliminated, go to Step 3.) (If noise is not heard, road test vehicle before continuing.) Tighten all bezel mounting screws. If noise is still present, add form as required to eliminate contact. (Laser and Daytona - remove metal reinforcement below the cluster opening and add foam.)

3. If noise persists, remove bezel. Check cluster mounting screws for undertorque. Repair heat staked lenses with Loc-Tite if noise is eliminated by touching the lens. A squeak in the cluster area is caused by the lens rubbing the cluster or bezel. Isolate with clear tape or foam. (Laser and Daytona - add a small piece of clear tape to stand-offs on cluster. Replace lens carefully, do not overtighten lens mounting screws.)

4. Check voltage limiter or low fuel relay by removing it from cluster. (Low fuel relay buzz occurs from 2800 to 3500 rpm's.) Remove cluster and check for wiring contacting defroster or A/C ducts.

5. If noise is unable to be reproduced, road test vehicle checking for steering column to panel contact. Trim or file panel to obtain clearance. Check list of failure codes for other possible causes.