2.7l manual hesitating during acceleration

[danielsprague]

Hi guys

Last Sunday I finally got my hands on a Surf, a 1996 3rd Gen 2.7l petrol (3RZ-FE) with a manual transmission (W59). These seem to be extremely rare and so I jumped on it, even though it's not quite perfect.

I'm very comfortable with diesel engines and injection systems, but I know basically nothing about the bits of a petrol engine which are not common with a diesel.

I need the truck to be ultra reliable, it seems to have a bit of a heating-up problem (I suspect a faulty thermostat or slightly blown head gasket), and so I'm going to rebuild most of the engine, hoping to leave the bottom-end alone.

There is a long to-do list on the truck, but the most pressing issue, after the heating was hesitation at around 1500 - 2000 rpm, which shook the vehicle quite strongly. All I can do is work my way along the line of things I suspect could be at fault, but I was wondering if anyone knew what this from experience? The idle also seems uneven, whether hot or cold.

The engine is also hard to crank when hot, though I will open a separate post about this.

Thanks

Daniel

[danielsprague]

Full engine rebuild done, so not sure what the problem was exactly. I suspect dirty injectors were causing the hesitation during acceleration (as the throttle position sensor is fine). I had the original injectors cleaned and never had problems again.

Uneven idle was fixed by replacing both the coolant and air temperature sensors in the EFI system (not the sensor which read out to the dashboard gauge).