93 buick lesabre
My '93 Pontiac Bonneville did this. If I understand the problem correctly, your car will move somewhat when you first start it up in the morning, but will not power forward after the first few minutes of operation. This is such a common problem with the early 90's General Motors front-wheel drive transaxles used on the mid-and-full-sized models that I am willing to bet the farm on this one. I really feel blessed to have one pitched over the plate for my first at bat with FixYa! Here's what's happening.
The automatic transaxle (front wheel drive vehicles combine the transmission and drive axles in one unti) are very complex mechanically, but quite simple to understand in theory. This is a hydraulic system . It relies on a fluid (transmission fluid) under very high pressure generated by the engine turning a pump (called the torque converter) and pumping the fluid into precise passages. Rubber or latex or some other strong, flexible sealing material keeps the pressure up and the fluid in the transaxle.
Your first, and really only function in this system is to check the fluid and keep it topped up with Dexron II, Dexron IIE or Dexron III ATF (Automatic Transmission Fluid). You can get this at auto parts stores, Wallmart and like stores or Jiffy Lube-type services. The dipstick for the transaxle is toward the rear and at about 1 o'clock of the engine compartment. ATF is red in color, do not confuse the engine oil dipstick (brown color oil) with the ATF dipstick. They are marked. Although low fluid level will cause this "driveability" problem, and would make your life so much simpler, low ATF is not your problem.
Your problem is worn or old brittle seals in the hydraulic system. I know this by the symptoms you described. The ATF is thickest when the car is "cold", meaning that running the engine and pumping the ATF through the very tight, precise passages has not yet raised the ambient temperature of the ATF from its "resting" temperature to its operational temperature. "Colder", thicker, ATF has lower viscosity-a measure of the ability of the molecules of the oil to flow. Basically, the "cold" ATF is compensating for the inability of the old, brittle seals in the transaxle to maintain proper pressure to drive the vechile forward. When the ATF warms (takes from less than a minute to a couple of minutes) the ATF becomes more viscous, it flows better, and can seep through the seals and lower the pressure in the hydraulic system to the point where no power is being relayed from the engine, through the transaxle to the drive (in your case, front) wheels and the car stops moving.
The bad news here is that diagnosing the problem is easy, repairing it is expensive. This is probably a $1500 to $3000 rebuild of the transaxle on a 14 or 15 year old car with a Blue Book value of $700 dollars or so. You could try to find used transaxle in a salvage yard; maybe get lucky and get one recently rebuilt from a wreck. If you are like me, and this happens to be the first brand-new from the dealer car you ever owned, your Lesabre will assume a semi-permanent spot in your driveway and will become a familiar topic of conversation with your spouse. Good luck, my friend.
Oct 06, 2008 |
1993 Buick LeSabre