Automania/Repair and Maintenance

AUTO QUESTIONS AND ANSWERS FOR WEEK 19

by Bob Hagin

Q. Since 1992, I have owned a 1989 Mercury Sable LS with the 3.8 liter engine. In '93 I had the radiator replaced at an independent garage and later in the same month I had a Mercury dealer replace all the coolant hoses as preventative maintenance at 49,000 miles. In '95 I noticed a slight coolant leak and the same dealer's shop replaced the water pump when the mileage was 69,000. The leak persisted and I traced it to the coolant overflow jar which I had replaced but the intermittent problem wasn't solved. The dealer's mechanic said that the head gaskets on the 3.8 liter Ford V6 engine had a reputation for leaking but my Sable doesn't overheat so I discount this as a cause of my coolant leakage. It seems that there is extra pressure building up somewhere so I replaced the radiator cap without success. I'm now resigned to adding about six to 10 ounces of coolant every three to five weeks. E.W. Virginia Beach, VA

A. Troubleshooting consists of about 60 percent observation and 40 percent perspiration and I don't think your mechanics have spent enough time checking out the problem. The first thing to do is to make sure that all the hose clamps on those new hoses are really tight. One that's a little loose can cause an intermittent leak as the engine warms up. If they're OK, thoroughly clean the engine, especially in the area of the freeze plugs. These small soft-iron cups fill the holes that are built into the heads and block when these parts are cast and can rust out or leak for various reasons. After the cleanup, run the car until it's up to operating temperature, install a radiator pressure pump and pump it up to about 17 PSI. Watch the gauge on the pump for two or three minutes and if it drops at all, it's going to show up as a leak.

Q. I have a 1996 Olds Ciera with the 3.1 liter V6 and an automatic overdrive transmission. The car seems to shift too early between first and second gear and the shifts are very hard. The dealer has replaced the servo, the entire transmission and tested other components. The factory rep contacted me and implied that they all do this. I find that hard to believe. The hard shift is annoying and noticeable to passengers as well as to the driver. I'd like to get this problem fixed. J.M. Hertford, NC

A. Saying that "...they all do it.." is an unacceptable cop-out, especially so if the rep hasn't driven the car. An easy way to check this out is to drive another car just like yours and if it shifts early and hard, the transmission and the shifting system were designed wrong. The head man of Oldsmobile public relations once sent me a letter telling me to send him complaint letters from Oldsmobile owners and I'm doing that with your transmission problem. He has been pretty reliable in the past so let me know if and when the Olds people take care of you.

Q. I have a 1984 Toyota Corolla with 106,000 miles on it. When the engine is cold there is no vibration in it but when it is hot and I take off in first gear, it vibrates pretty badly. After I get up to speed, the engine smooths out but if I stop or slow down and then accelerate, around 15 to 25 MPH the car vibrates again. Do you think it is a problem with the transmission? It is an automatic.

A. As vehicles get older and becomes high-milers, they need more care than when they were in their prime. They're a lot like people that way. If the vibration was in the transmission or in the drive train, I'd suspect that the problem would show up when the car was hot or cold. Since it only happens when it gets warmed up and put under an acceleration load, I suspect that it's a tune-up problem. It could be an engine vacuum leak (loose or cracked vacuum hose, loose carburetor or manifold bolts, etc.) that open up as the engine expands from heat or even worn spark plugs or plug wires. Better have a pro check it out.