Hi folks! I'm a bit stuck and wondering if anybody can help.

I've just bought myself an old 2002 L200 for work, and while driving up a hill the other day the EML came on. Revs and power decreased dramatically, and I had to stop. After a few minutes the engine started fine, with no light but it came on again pretty soon afterwards.

It's been almost constant ever since (occasionally it turns off when I start the engine but it's usually on). It seems to drive ok (although it's my first truck so I'm not really sure what to expect) but I took it to a garage yesterday and it threw up two codes on their scanner:

Main Throttle Solenoid Valve

Over boost variable geometry control pressure sensor system malfunction.


From looking around online, and through this forum, it seems that those two codes are 41 and 49, fairly common but awkward to accurately diagnose. I've read a whole lot of stuff about cleaning actuator rods, adjusting turbo max boost screws, checking for faulty pipes etc etc but to be honest I'm completely out of my depth! I wouldn't know where to look for stuff and don't want to start fiddling with the turbo or removing sensors etc without really knowing what I'm doing.

I've got it booked in to a Mitsy specialist next week but I'm wondering if anybody here might know what it could be so I have a better idea what to expect!

Cheers for any help or info, if there's anything I can clarify to make it easier let me know!

Will

just over boost most probably u can try turning the max boost down

Thanks for the quick reply! Much appreciated.

I'm guessing that's one of the two screws I can see on the side of the turbo?

Do you think that would solve the fact that the EML simply doesn't go out after turning the key, or is adjusting the max boost something that's more suited to EML coming on while driving?

Cheers

ah maybe u have 2 issues then over boost will reset once the ignition is off for 10 seconds

your other fault code points to one of the solenoids under the throttle body the brown one IIRC

Hmm. Well if definitely doesn't go out after 10 seconds! It's not gone out for about a week.

When I look at the throttle body, there's a pair of solenoid valves in clear view on top of it, brown and black. The brown one is K5T48272 and the black one is K5T46494. Are these the ones that the code is referring to, or are there another pair hidden away somewhere?

Looking online, it seems that those two come under the part ID MR577099 and are called lots of different things, including emissions solenoid valves. When I search for "Main Throttle Solenoid valve" I get a whole load of other numbers, including MR404682 and MR204853. Do you know if these are the ones I should be replacing, and where they might be hiding? I can't seem to find any diagrams showing the position of the solenoid valves anywhere.

Thanks again!

Will

Ok, so ended up taking it to a Mitsy specialist and they analysed both solenoid valves as faulty. Had them replaced, and the EML went out.

Everything was working absolutely fine, until I tried going uphill today, and on came the EML again. This time it's going out when the engine is turned off, so I'm guessing that is more likely to be boost issues?

The two screws on the turbo are rusty as hell, and the fella at the garage said he was glad it wasn't those that he had to touch because he was worried about shredding them. It's the top one that I need to screw in, as far as I can tell and it seems that people recommend only doing 1/4 turn at a time, so before I go shearing off turbo screws does it definitely sound like that's the issue?