Popping noise in 1993 Lexus upon accelaration` on 1993 Lexus GS300

When I was driving home on the highway at about 60MPH I had to accelerate to get past a slow driver..I then heard a quick popping sound and continued on.I have not hear that sound from this car before. Now on idle or slow speeds it seems a bit slow and idles more slowly than before. Gas is very low, but I don't know if that's a factor. The popping sound alarmed me a bit. What might this be?

by in Westminster, CO on April 05, 2011
2 answers
ANSWER by on April 05, 2011
It may be hard to tell without looking at the car but the timing belt may have slipped a tooth or 2. Regardless of what may be the cause I* would have it looked at sooner rather than later.
ANSWER by on April 20, 2011
This is exactly what happened to me a week ago in my 94 ES! I just bought it two weeks ago with 192,000 miles. With some mechanical background, I immediately thought the timing belt broke, however when I pulled the timing belt covers off to inspect the belt, I found the belt and the upper idler/roller looked new. The bar code was still readable and when I turned the crank pulley over, the cams would turn with the crank showing the belt had not given. I should say that after the loud "pop", the car died as though a plug had been pulled from its power source. I lost powersteering, then the engine shut off. Fortunatly I was on the frontage road about to get on the highway when it happened, so I was able to steer it into a shopping center parking spot before it lost momentum. But the driving about 40-50 miles per hour, then having to pass someone going to slow was all the same. I'm afraid I'll need to pull the valve covers to inspect the valve train for any damage as well as verify that the timing did not "jump". If it did, I don't know how. Any tips/pointers would be welcome at this time.