1995 Hiace 3.0 Diesel: Engine Light Comes On - Help!

[Jeff Viggiano]

Hi all! I'm here in the US, where these were never originally imported, and, as such, most mechanics here don't want to get involved, especially if it's a diesel......so, hoping maybe somebody here can shed some light on this: Car runs great when it's first started, smooth, quiet (for a diesel)...after about 20 minutes to half an hour of driving, the engine light comes on. When the light comes on, there's also a sound that sounds almost like a lightly squeaking fan belt, and the engine's a little rough....not very, but you can notice it....if you hit the gas hard, you do feel a sort of miss or stammer.....the temp's good, everything's good, except for the issues I stated.....Then you shut the car off, come back a few hours later, and it fires up & runs great again, like nothing happened, until about a half hour later, then it's the whole cycle all over again. I thought maybe the fuel filter was getting clogged, so I changed that, no help.....Thanks in advance, hopefully it's nothing major!