Toyota Camry Highlander and Lexus RX300 Transmission Throttle Lag Hesitation

We have seen a lot of transmission complaints in the Toyota Camry, Solara, Highlander and Lexus RX300. It is characterized by a major hesitation when trying to accelerate after a slow down to under 15 mph. A recent customer’s description was, “Super scary when you just committed the car into traffic. I thought I had just run out of gas.” This is not a transmission problem; it is called ‘throttle lag’ and occurs on some Toyota and Lexus ‘drive by wire’ (electronically controlled gas pedal in place of a conventional throttle cable) cars and SUV’s.

You may experience this problem only once, or 10 times a day. It can be difficult to diagnose, because it feels like a transmission problem. After purchasing a 2004 Toyota, I took it in three times while under warranty for this same issue, but the technician couldn’t locate the cause of the problem. A few months later a customer came in with an RX300 with the same issue. He had been told that the transmission was the culprit. Although I couldn’t locate the cause, I knew it wasn’t a transmission problem.

Toyota Transmission TSB

The manufacturer keeps track of known problems, complaints and corrections, creating a list of TSB’s (Technical Service Bulletins) for each model. They locate the pertinent TSB by searching in the computer using details about the complaint. It occurred to me that the reason the technicians at the dealer couldn’t find the TSB was because they were searching for a transmission related TSB.

Toyota Dealer Computer Flash Relearn

The Toyota technician who had been stumped by this problem on my car was eager to help me find the problem. Both cars were doing the same thing, so we believed a TSB would exist, and that it probably spanned different models. Some vehicles have hundreds of TSB’s, so it’s important to match the description during the search. Removing the term ‘transmission’ brought up a completely different list of TSB’s. The correct TSB was found by using ‘throttle lag’, and was TSB# TC006-05 on my 2004 Solara V6. This problem can be corrected by having the ECT (Engine Computer) reprogrammed at the Toyota or Lexus dealer. This shows how difficult diagnosis can be.