Maldge

My 99 impreza Turbo 2000 has a Superchip fitted and I believe is soldered in to the ECU. Im wanting to put my car back to standard and would like to know if anyone has any advice on how to remove it? Im not sure where the Superchip is fitted. I think it also has a boost valve which I think is related to the Superchip but again im not sure where its located and how to remove it.

Splitpin

Maldge, I've never actually seen one of these chips but, unless someone comes along who's actually been there and done that, if you can close-up photograph the relevant areas of the car I should be able to tell you what isn't as it should be, and how to remove it.

Logic would suggest that it's a little more complicated than simply unplugging. From what you're saying it sounds as though there's a manual boost controller plus a defender type gadget facilitating running the car near or above its normal fuel cut level. If so it will likely be spliced into some of the sensor signal input lines and thus you will need to reconnect these back as they were or you'll be dealing with check engine lights and limp mode.

If you could, initially at least, take some photos of the wiring loom as it connects to the ECU, and also remove the ECU top cover and take a couple of pics of the PCB itself, it'll be easy to tell whether something that shouldn't be there is hanging around.

Similarly if you could photograph the upper front of the turbo, showing the compressor bleed air outlet and the wastegate actuator we can tell you straight away what's what.

joey_turbo

iTrader: (26)

Probably better to get a standard ECU for your year. Can pick them up for under 50GBP, and you should be able to sell yours for the same or more.

Maldge

Yeah I suppose that is an option. I could do with finding out what wiring has been spliced in to and what has been done before I buy one.

Maldge

Great stuff mate, I will get some pics up ASAP.

Splitpin

Whoa, one step at a time. Your suggestion only has any merit if the clamp/defender/etc is actually soldered into the ECU, rather than into the car's wiring loom, a question regarding which there's currently considerable doubt. This sort of thing is normally connected to the loom, but we'll see.

Until then it's a bit premature to suggest this.

jodydid

i have seen these on ebay and the splice in to the loom by the ecu should be under the metal cover in the passengers foot well

joey_turbo

iTrader: (26)

True. I assumed it was like most of the other Superchips that are adjusted fueling eeproms.

They appear to be spliced in jto the loom on impreza's as you say.

There is a pic on ebay of the offending item: http://cgi.ebay.co.uk/abc-ecu-superc...-/270536509942

Its mentioned on a few other forums that once its disconnected, and the ECU cleared, there shouldn't be any problems.

There is always the issue of the boost controller maybe being set a little high, but that can be removed/adjusted fairly easy.

Maldge

Here are a few pics under the bonnet and of the ecu

Splitpin

Okay Maldge, good pics, they show us everything we need to know. Going from the top, and as you've no doubt already twigged, the Superchip is definitely external - so no reason/benefit gained from flogging your current ECU and replacing it with a standard one, it already is.

The second pic down shows you where the chip is getting its ground from the eyelet beneath the ECU mounting nut. You can either just cut this black wire, or, better, take the nut off and pull the eyelet off the stud.

The third pic shows you where the red wire on the Superchip is connected. It's piggybacking off the yellow wire with the blue stripe - this is the ECU main power line. You can cut the red wire off and insulate what remains in the car, or, better, if you have the ability, remove the insulation, desolder (or decrimp) the red wire completely, and make it good. This wire is only powered when the ignition is on so you don't need to pull the battery while you work on it.

This appears to leave two more wires on the chip, which look from your pics like they're spliced into the yellow wire with the black stripe and silver dots going into pin 7 of the blue plug, which is, unsurprisingly, the signal wire from the manifold absolute pressure sensor. To complete the removal of the chip, disconnect the remaining two wires from the severed ends of the pressure sensor cable, and rejoin the two ends back to each other (ideally via a solder joint) and insulate it.

The fifth pic shows where the bleed valve has been spliced into the boost control pipework above the turbo - you can immediately see the difference between the grey Subaru boost hose and the blue aftermarket stuff. You can see where the blue silicone hose from the bleed valve runs to a t-piece - with another short length of the blue stuff connecting the tee to the wastegate actuator.

To remove the valve, pinch and slide back the hose clip securing the grey pipe to the left of the two tees, pull the tee out of the grey hose, and pull the other blue pipe off the wastegate actuator.

Then try and fit the now open end of the grey hose onto the wastegate actuator and secure it with the clip. If it's now too short to reach, replace it with a length cut from the long blue pipe.

That leaves you with the bleed valve stuck down by the side of the boost control solenoid in your final pic and its associated pipe. Presumably it's been screwed onto the mounting plate but either way, removal should be pretty self-explanatory. It isn't doing anything now so you could just leave it there if push came to shove.

Maldge

Thanks Splitpin, thats great. I will have a go at removing it as you said. Im not 100% sure that the yellow wire with the black stripe & silver dots will be long enough to connect back together. Obviously I will check that before taking anything off. I will be glad to get the thing off my car now tbh. Thanks again.