Hey all, I've recently purchased a '97 4m40 TD series 2 l400 for $6500 AUD (about $4200 USD) with 237000 kms on the odometer. Obviously at this price I've been expecting problems but so far its actually been running quite well, especially as I've just replaced the oil, fuel and air filters, glow plugs and cleaned the intercooler, I even daily the thing to and from work. The previous owner says the head has all been replaced. It doesn't blow any smoke and it starts up quickly, however twice now as I've left home for work and driven a few hundred meters and come to a stop, as I idle it'll become shaky for a second and stall. Perhaps I'm simply not letting the engine run for long enough to heat up in the morning but maybe I'm missing something, as it idles fine and doesn't stall when I start it up in the morning and only stalls after I've driven a little bit and come to a stop.
The car also acts strangely when I get on to the freeway and start going 110km/h. On some days, the check engine light will already be on, but I can cruise at 110 at like 2600rpm smoothly and even go to 120km/h under 3000rpm if I want to. Sometimes the check engine light will be off, I reach 100-110 km/h and then the check engine light will come on and I feel a small power loss and have to cruise at 105-110km/h at 2900-3000rpm and really cant get much faster. My dad thinks its the wind but I don't know. Maybe its just typical van things and I'm expecting too much, but it seems pretty inconsistent.
I stuck a paperclip in the obd connector and I got codes 12 (boost pressure sensor) and 41 (throttle valve solenoid). Researching this code combo brought me to have a look at the vacuum diaphragm and solenoid thing. Apparently the common fix is to bypass the idle valve, but after having a look at mine the idle has already been bypassed and plugged straight into the vacuum. The solenoid line just loops back in on itself. I'm assuming this is why I'm getting the error code, but it doesn't address my problem and I'm not really sure where to go from here. I'm not exactly mechanically inclined myself so any and all help and ideas would be much appreciated.
The car also acts strangely when I get on to the freeway and start going 110km/h. On some days, the check engine light will already be on, but I can cruise at 110 at like 2600rpm smoothly and even go to 120km/h under 3000rpm if I want to. Sometimes the check engine light will be off, I reach 100-110 km/h and then the check engine light will come on and I feel a small power loss and have to cruise at 105-110km/h at 2900-3000rpm and really cant get much faster. My dad thinks its the wind but I don't know. Maybe its just typical van things and I'm expecting too much, but it seems pretty inconsistent.
I stuck a paperclip in the obd connector and I got codes 12 (boost pressure sensor) and 41 (throttle valve solenoid). Researching this code combo brought me to have a look at the vacuum diaphragm and solenoid thing. Apparently the common fix is to bypass the idle valve, but after having a look at mine the idle has already been bypassed and plugged straight into the vacuum. The solenoid line just loops back in on itself. I'm assuming this is why I'm getting the error code, but it doesn't address my problem and I'm not really sure where to go from here. I'm not exactly mechanically inclined myself so any and all help and ideas would be much appreciated.
