So I have a 1991 Townace with 126,000 km on the clock, which was running great before it broke down. Here's some background on my repair, unfortunately my regular mechanic is not a diesel expert, but said he could fix it since I have the 2C manual.
I was driving on the motorway at a consistent speed of 110km, when all of the sudden the engine took off and accelerated uncontrollably. This action was a surprised and in a moment of shock I shifted in neutral, which then the engine redlined for 6-10 seconds before shutting off. After it was towed to my mechanic, he was able to start and the idle the engine fine, but when accelerating it would flood, and want to stall. Before the breakdown, I had noticed a small decrease in power when going up hills and also had refuel the van, not sure if these details are related to the whole story.
My mechanic was concerned it was not filled with diesel because of the smell, so he drain the fuel tank and system and said the color was odd too. I'm 100% percent the tank was filled due to the pump was a diesel-only fuel pump at the station. Maybe it was bad diesel, could this be related to the unintentional acceleration?
With the repairs at hand, it was recommended that we replace the timing belt, tensioners, water pump, because the injection pump was the likely core issue with the breakdown and these items were due for replacement. We also replaced the fuel filter and the air filter, I think as well.
After rebuilding the fuel injection pump (by a specialist) and it was confirmed during the rebuild a tooth on the govern gear had sheared and caused the pump to over dose the engine.
It gets worse... after the injection pumped was serviced and reconnected to the engine, the engine was turned over for the first time in months and possibly due to condensation within the engine from sitting semi-dismantled during the winter, the valves were stuck and the cam shaft cracked. So an aftermarket head assembly was order (all new cam shaft, valves, head and was advise any adjustments were not needed, as they are set to spec when assembly) and bolted on with a new gasket. However, could this be the issue, the shims should be fine right? If further tuning is need here, what do we look for?
And so today, we are at the current problem where the engine sounds great, but has poor acceleration and has a maximum speed of 80-90km. My mechanic says he's followed the manual and troubleshooting guide but is stuck at this point. He says it feels fuel starved still.
I'm about to switch mechanic and any guidance to avoid dead ends, would be greatly appreciated as I have spend a good deal of money without a solution.