This was an extremely common problem on late 1980's to mid 1990's GM front-wheel-drive cars. It is caused by wear in the spool valve housing, part of the rack and pinion steering gear. The clue is it always occurs at first when turning in one direction, not both ways. The power assist will come back intermittently once the power steering fluid has warmed up. The fact you still have power assist to the right proves the pump is okay. The lack of power assist will become worse over time, and if you ignore this long enough, it will start to affect turning right too.
GM's fix for this was to replace the spool valve assembly with its Teflon sealing rings. The hope was this would hold up long enough to get the cars out of the 50,000-mile warranty, then it was up to the owners to pay for the proper repairs when this occurred again.
The new sealing rings solved the problem for a little while, but the real cause of this was those rings wore grooves into the soft aluminum housing. The proper repair was to replace the rack and pinion steering gear. It took the aftermarket rebuilder industry to come up with the best solution. Moog, and now other rebuilders, bore out the housing, then press in a stainless steel liner. Those hold up forever to this type of wear. Due to the relatively low cost of rebuilt steering gears compared to just fifteen years ago, they are a much better value than finding a used one in a salvage yard. The exception would be since this is such a common problem, a lot of cars in the salvage yards will already have one of these rebuilt units in them.
Saturday, September 19th, 2020 AT 2:29 PM
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