Toyota 7FGCU30 - serial # 63935 - year-1992?. Engine will start normal but several times during the day the motor will start to surge. Some times it will smell from the exhaust.( propane fuel is used). It will stop surging and run normal just as quick as it started. We also notice that the hydraulics work very slow compared to a 7FGCU25 that we have. When you step on throttle fast the motor will only come up a little and level out, almost bogging down. If you throttle up when trying to lift a good sized pallet it will stall engine. This has a throttle cable that is used, do not see any wires going to throttle body, only a vacuum line to base below throttle shaft. Motor acts like it has governor. There is a **** at base of throttle body that can be adjusted and is safety wired.