Lexus' engine covering could be noise reducer

| Saturday, May 4, 2013, 12:01 a.m.

Q: I purchased a 2013 Lexus FX 350. Under the hood, the engine is covered with a plastic shroud. No part of the engine is visible. Does this shroud provide any function for the running of the engine, or is it just for looks? I would like to remove the shroud. If anything goes wrong with the engine while I am on the road, I would have to take it off first — which may not be safe at the time.

A: I checked out the appearance of your engine cover. It's more of an engine bay cover, blocking everything from view except a portal under which another plastic cover hides the engine. This is nuts, as you can't get a look at the battery terminals, belts, hoses or much else without removing it or perhaps a small hatch or two. I'm thinking the main benefits are noise reduction and an impression of “there's nothing in here that could give you trouble.”

Maybe buy a good LED flashlight and telescopic inspection mirror to check on things? Truthfully, there isn't much one can fix anymore alongside the road, assuming hoses, belts and general maintenance are kept up.

Q: Over my long driving life, I've been rear-ended three times. I've finally replaced the brake and collision avoidance lights in my 2005 Chrysler Town & Country with very bright LEDs. This is fine, and, as expected, the turn-signal flasher operates much faster due to the change in resistance. I understand I can install resistors or change out the flasher unit. What is your preferred method?

A: Jim, I agree that LED, or light-emitting diode, lights can offer a higher level of visibility, and they illuminate considerably faster than traditional incandescent bulbs. This can help the person behind you react perhaps 20-30 feet sooner in a sudden-stop maneuver. Many companies market LED conversion units that install in place of incandescent bulbs. Most work well, but because LED lights draw less electrical current, a vehicle's turns signal flasher and/or lamp-out warning module often believes there's a problem. The flasher units used on older vehicles will flash more slowly or not at all, as there isn't sufficient electrical current to cycle the bi-metal heater inside. Electronic flashers on current vehicles flash considerably faster than normal when a bulb is burnt out, because of lower-than-usual current, and are fooled by the LED lights.

LED compatible flasher units are available for vehicles still using a standard two- or three-terminal flasher.

Your Town and Country, as well as many other recent vehicles, unfortunately integrates the flasher into the body control module, or a unique, proprietary flasher module. In this case resistors can be added, wired in parallel with the LED lamps. The resistors, which are widely marketed for this purpose, convert electricity to heat, imitating the original incandescent bulbs and making the flasher and/or lamp-out module happy again.

This typically works OK, as long as the resistor is carefully mounted to prevent melting/damage to nearby components.

Brad Bergholdt is an automotive technology instructor at Evergreen Valley College in San Jose, Calif. Readers may send him email at; he cannot make personal replies.

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