Automania/Repair & Maintenance

AUTO QUESTIONS AND ANSWERS FOR WEEK 11 YEAR 2000

by Bob Hagin

Q. I have a 1989 Itasca Motorhome with a Chevy P-30 chassis. It has a 454 CID V8 engine, carburated, with dual exhaust. I believe the engine is actually an '89. When we were returning from a trip last September heading up a steep mountain pass, I heard a loud bang like something came loose and hit the engine compartment walls. Then the engine started to vibrate. When we got home I checked the dust cover on the transmission to see if a weight had broken loose. Then I thought I would check the plugs and the Number Two lug was broken in the boot. So I replaced the plugs. Still it vibrated. I was told that it could be a broken rocker arm so I removed valve covers (no small task) and they are all intact and working. I was told it could be a stuck exhaust valve so I did a compression check. I had a low of 140 PSI and a high of 155. If I can't find out what it is, we won't be able to take any trips. Our fuel mileage went from a high of 7 MPG to 4.8 on our last trip. B.B Placerville, CA

A. Any sudden vibration is a serious problem. I assume that you carefully examined your engine compartment for signs of something bouncing around. Try running the engine with all the drive belts removed to see if one of the ancillary units is at fault. The vibration damper on the nose of the crankshaft is a two-piece concentric affair and the rubber-like bonding agent sometimes breaks loose and disturbs the balance. A quick check here would be to check the ignition timing and if the marks are way off, it could the problem. Don't discount a broken valve spring or a bent pushrod. Remove the rockers and pushrods and examine the valve springs carefully. If all this fails, you'll have to call in professional help for exploratory surgery.

Q. I own a '98 Chrysler Town & country with 30,000 miles. The car has been essentially trouble-free, but it handles poorly in the snow - slipping and sliding in turns, unable to ascend small grades and getting stuck. It has the original Michelin all-season radials (215/65R16), but it performed poorly in the snow even when it was new. Would using snow tires (i.e. Blizzaks) during the winter months improve its winter performance? Would the improvement justify the expense of snow tires? J.V. Wheaton, IL

A. It's too late to change your original purchase, but you should have opted for a minivan with all-wheel drive, or any number of other bad-weather performance options that were available even it meant buying another brand. Relatively poor performance in the snow is a characteristic feature of anything but all-wheel or four-wheel drive vehicles, according to my ski-fanatic sons. Snow tires help, but many drivers don't like the noise and vibration they make on dry pavement. Some drivers keep an extra set of wheels and tires in their garage just for winter, then change them back to the originals in late spring.

Q. We have a 1997 Plymouth Neon sedan with a four cylinder engine and standard transmission. The car only has 48,000 miles on it and although we've taken care of it exactly like the owner's manual recommends, we have had to have three head gaskets installed and one time it required a new cylinder head. We want to sell the car, but we don't want to sell it to someone who will have the same problem. Can our Neon be made reliable? The shop that's been doing the jobs has been as helpful as possible, but they don't seem to know how the make the job last. R.M. Chesapeake, VA

A. At one time, I thought that the Neon heads were cracking and should have been examined more carefully when the repair job was done but now I believe the problem is in the original design of the head gasket. One of the major aftermarket gasket makers now claims to have developed a head gasket for the Neon that will last if the head isn't cracked or warped.