$25 Boost Solenoid (Bog Valve) replacement for SE

[AzzA68]

G'day,

No doubt anyone with an SE has either encountered or heard of the dreaded Bog... One cause is the 3 way solenoid that switches the Boost Sensor in and out of the MAP hose line.

The Boost Sensor is in front of the fuse box under the bonnet, it's labeled Boost for easy finding.

The solenoid is hidden under the bracket, nearer the fender. It's wires enter from the rear, the hoses from the front. Is labeled Mitsubishi.

This solenoid is known to be a PITA. It commonly fails by 100k kms. And it does so intermittently and flakey. Cleaning it can help. Tightening up the spade connectors can help. But ultimately it's a consumable part like the BOV. So, replace it.

OEM is expensive, so aftermarket is far cheaper.

Search eBay for DC12V 5.4W MAC Solenoid Valve 35A-AAA-DDBA-1BA With Brass Silencer.

Concentrate the search on the part number but ensure the other values match up on the description, and don't pay over $25-35 for one...unless you like being ripped off, in which case I have some bridge shares you might be interested in.

Get the valve with the brass fittings. You won't use the barbs, they are too big for our hose, but you'll need the brass filter.

You'll also need two 1/8" NPT to 3/16 hose barbs, to match the hoses on the SE. Buy online or source locally, cost me $12 to have some odd sized ones turned down to fit but I live in BFNW... Shop around.

It's a good chance to check the hoses you've got; chances are they're getting hard or cracking. Replace as required.

Plumb the manifold house to port 2, the Boost Sensor to port 1, and the filter on port 3.

I used some RTV silicon to ensure the threads sealed without over tightening.

Remove the old solenoid valve and secure the new one under the frame with a big fat cable tie. Or get crafty and drill some mounting holes.

You'll need two 6.3mm spade terminals, male, to crimp onto the new wires. Secure them into the OEM plug with some small cable ties or heatshrink. Use a small screw driver or pick to close up the female spade connectors; they get loose with age. (Just like some old girls I know.) Polarity doesn't matter.

You're done.

From my experience, boost should now come in a little earlier and not peak as high as before. My guess is the old, failing, solenoid was causing noise on the Boost readings so over-shoot and increased lag resulted. Overall the drive is better and it's not gone into the "limp mode" like condition since doing this job. (Fuel trim figures get all screwed up until you turn off and back on the ECU.)

HTH

Cheers,
AzzA

[ManiacLachy]

And then when you finally move to a standalone ECU, you can reuse this solenoid for your boost control

[AzzA68]

That will cost me more like $25k... Roughly enough for another low mileage SE, to keep unadulterated, and enough beer coupons for NitroDann to get 300 killawasps out of my present SE.

Just like that silly old shampoo advert:
It won't happen over night, but it will happen.

And then I can spend the rest of the kids inheritance replacing rear tyres at a ratio of something like 8:1 rear:front...if I go easy enough on the pedal. ;-)

Tick tock.... Tick tock...

[ManiacLachy]

$25k, if you go all out in one hit. I like to do it in small increments. Death by 1000 cuts style.

ECU with boost control and some Dann time will get you a nice 220-230whp and you'll be pretty happy. No more bog, no more hesitation, no more sudden 10psi boost cut. And leave you happy enough to delay the full rebuild and turbo upgrade (for a little while at least).

[AzzA68]

You're right; I could just settle for 3"exhaust, injectors, intake, and ECU with fabulous tuning. Would be an excuse for an interstate diving holiday.

No!

Stop trying to corrupt me!

Damn FOMO!

Later in the year, stop rushing me; there's an order to things that sometimes must be followed. (Bugger it all. Stupid budgets.)

[ManiacLachy]

You'll fall to the darkside soon enough. It's corrupting you already
(I suggest you add flex fuel to that list, E85 is a hell of a thing!)

Unfortunately once you're here, there's a darkerside - and it's calling me. But there's no way I can afford a built motor! I don't need more power...

Stupid budgets,