Ray_200

Hi there I have a v4 wrx import which has v4 sti engine. It runs great but only seems to boost to .7 bar, I am fairly we to subarus. Is this normal or is it something that can be fixed with a new actuator ? It's engine is standard except a full exhaust (straight) and dump valve. I plan to mod more in the new year but my priority is getting it working fine before I continue.
Also I am led to believe that the only way I can up the boost to 1 bar is to fit simtek or power fc. Was planning this for future anyway but wanted to k ow if there was away to run 1 bar safe before ecu change?

MattJ85

iTrader: (3)

I have a newage wrx - but mines boost upto 1.2 bar with normal ecu

Sprint Chief

The car should be boosting more than that as standard. Should be at least a bar, even with standard engine management. (Unless the car is a JDM wagon or an auto, in which case the boost is not far out).

Assuming you have a WRX saloon, the level you are seeing does sound like the default wastegate actuator pressure. Problems could be caused by the boost control solenoid or associated pipework. It could be the ECU has put you in limp home mode and his holding back the boost (although this is usually accompanied by a check engine light). Check the boost solenoid is working using the green test mode connectors and turning the ignition on (you should get a clicking near the driver's side front suspension turret). Check for codes using the black read memory connectors, and try cleaning out the boost solenoid with brake cleaner.

Also: it might be worth finding out exactly what you have under the bonnet. Does it have an STi short engine or heads as well? The heads breathe quite differently so the standard map might not be suitable - but then an STi ecu wouldn't be right either, unless you have the right turbo etc. It would probably be worth considering getting it remapped, you stand to gain a few horses that way as well, but it is important to get it running right before mapping.

You have more ecu options available to you than those you listed above!

Ray_200

It is v4 sti with td05 and correct ecu etc, wondered if it my be actuator giving me problem. Have no cel and it runs fine, what would be the the easiest way to run 1 bar before taking it to engine tuner Alan Jeffries ?

Sprint Chief

OK, that info confirms it definitely should be making more than 0.7 bar. (v4 STi didn't come with a TD05 though, should be a VF24 from memory)

Has the car always been at 0.7 bar since the engine+ancillaries swap, or was it working better than this in the past?

The boost control pipework is pretty simple and straightforward to check. Simplest checks first: make sure the plumbing is correct (the right pipes to the right ports) and the restrictor pill is in the pipework as it should be. Check none of the pipes look damaged. If they are, replace them (being sure to keep restrictor pills in place as needed).

If all is good, clean out the boost solenoid with brake cleaner. find the two green test connectors under the dash by the steering column. Connect them together and turn the ignition on. Check the boost solenoid is clicking away. Ignition off, and disconnect the green test connectors. While you're there, turn the ignition on and connect the black read memory connectors, and make sure you get the "all clear" (checking engine light flashing half second on / half second off).

Might be worth checking whether the actuator arm is loose as well. You can try it by hand. It should move a little along its length, but it shouldn't be loose or floppy.