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jjmiller182
27-02-2017, 09:09 PM
Hey guys I've had a read at the old posts and I'm pretty sure if I spent long enough and took bits out of different posts I could piece together an answer but I figured I'd just ask in case anyone knows anything off the top of there head. My issue is that in anything above 3rd which is quite happy sitting at around 14psi I get a big spike in boost to the point of it red lining on the gauge the ecu light will flash on at around 18psi and go off as soon as i come off the accelerator. I've had a look at the hoses from the mbc and there all good I've actually replaced the one coming from the inlet so I'm pretty sure that's not the issue. Has anyone got any ideas ?

Confused
27-02-2017, 09:13 PM
Do you know if your ECU has been tweaked?

It sounds like it could be 'Check Engine on Knock' - that level of boost is causing knock within the engine, and that light could be a warning.

However, if your ECU hasn't been played with and is completely standard, there's no reason why the light should come on under those circumstances.

I would do a flashy dash, to check that there are no other fault codes stored, just to be on the safe side.

Davezj
27-02-2017, 09:48 PM
go with garry's suggestion.

i would be surprised if you could hit 18psi in 3rd without hitting fuel cut (a complete and dramatic jolting loss of power, then it will come back about a second later).

jjmiller182
27-02-2017, 10:12 PM
I will do a flashy light check thing in the morning I know there's a few things that come up speed sensor being one but that is on the abs side of things. The way ive wrote that is also pretty bad I meant in 3rd it's fine it's in 4th that there seems to be no control and it spikes/gives me an ecu light. As far as the ECU is concerned I'm not actually sure what has been done to it I'm pretty sure the previous owner (andy/aboo) did have something done will check that tomorrow too

jjmiller182
27-02-2017, 10:16 PM
It didn't take as long as I thought the ecu has been remapped with anti lag

Nick Mann
27-02-2017, 10:23 PM
Yep, so the ECU will have a setting to light up the check engine light if the ecu is detecting knock. The ECU is detecting knock at 18psi!

jjmiller182
27-02-2017, 10:27 PM
Well thats awesome :/ I've tried turning the boost controller down and it's at what seems like minimum but there's a fair possibility that the threads need cleaned and it will shut off more will have a play with it tomorrow and see what happens

Nick Mann
28-02-2017, 07:54 PM
Did you add the mbc? Stock ecu boost control is often better and if the ecu has been flashed then it might also be set for raised boost.

jjmiller182
28-02-2017, 08:18 PM
No I didn't fit it but Had a look today and found out that there's no actual control element to the mbc as in the spring and ball element of it isn't there lol so oredered a new one of them today

Confused
28-02-2017, 10:20 PM
I agree with Nick, take the MBC out of the equation, plumb it all back to stock, and let the ECU deal with it - at least until you are sure that it's working properly.

Davezj
01-03-2017, 01:35 AM
i know some people have used an MBC as a max boost limiter only there are quite good at clamping the boost at max level and then use some other kind of boost control blow the max clamped boost setting of the mbc.
but if your mbc has no ball and spring inside it, it will not be doing anything. is it actually plumbed in.