Surging after Remap

[speedsix]

Cheers flash, battery and a TB reset? How long do I need to disconnect the battery for?

It does seem tweaking the map has caused it to go screwy again. It's like the boost is going up so fast the ecu sh*ts itself, tries to reel the boost back in and then boost it back up etc. etc.

Revo mentioned the DV but I can't see how fluctuating boost has anything to do with the DV?? If it's not the N75 what else could it be? Surely if there were a leak it wouldn't hold such high pressure?

Holding 24psi was a bit worrying

 

[speedsix]

Just disconnected the battery followed by a TB reset. Boost fluctuates still but it's not too bad unless pulling from very low revs in top where the needle can flap about as it reaches peak boost.

Really need someone to take a look at it to confirm there's a problem but I've no idea who?

 

[phatchoonz1]

phatchoons, have you mentioned the problem to Revo atall?

Nope, i've never really thought too much about it to be honest, as it only really happens when the car is fully loaded with people and you boot it. But now that you've mentioned it, it's kinda made me think about it a bit more! I would say that if I didn't have the boost gauge i'd probably never have noticed it, but having the gauge stuck in your face kinda draws your attention to the fact that it's doing it! Once you've seen that it's doing it, it is also possible to feel (and hear) the car doing it.

I've certainly not thought of it as a software problem, and hence haven't mentioned it to revo. But thinking about it, it may be worth an email!

Never managed to get my logs done the other night... Laptop battery was flat. Will hopefully have another go tomorrow after work though.

 

[Pabs]

its not a revo problem, otherwise it would exist on every revo remap they do. After all, it is a "generic" remap

Mine did it, but without ANY changes to the remap it was resolved - therefore it was the hardware.

Revo might know what causes it though... I know if you do a search on here you'll find lots of posts/threads by me on it.

 

[speedsix]

I may be making something out of nothing, if I didn't have the noisy induction and guage I doubt I'd notice it.

I'd be interested to hear what the needle does on others guages when they floor it and build the boost from low revs in 5th/6th.

Mine kinda peaks ~22psi, drops to 18 and then bounces to 20 before settling on 18. Sometimes it's just 'a bit of a wobble' sometimes it can bounce quite a bit.

It just feels like the N75 is not quick enough to react.


Cheers

Dom

 

[DPJ]

The needle flickers in front of you, properly done Vag-Com logs provide hard evidence..................

 

[speedsix]

The needle flickers in front of you

What do you mean mate? Does your guage bounce a bit when flooring it in low revs in a high gear? Not exactly something you do often I know.

I can't do any logs for a week, don't have a laptop atm.

I think I'm just going to leave it, it's not really a big problem I just wanted to be sure I'm not doing any damage.

This morning on the motorway I was rolling in 6th, 3000rpm and flooring it. If I had some boost it would usually just peak and then settle. If the boost had dropped completely and I stamped on the loud pedal the needle would sometimes shoot up to a peak of 22 ish, instantly drop to 18, bounce back to 20 and then hold 18.

Cheers for everyone's help

Dom

 

[speedsix]

Can I safely adjust the screw on the N75 if I mark it's original position?

I may try a 'C' N75 valve of a friend's Ibiza.

 

[cordobabrendy]

if you are revo'd stick to the standard valve, if i was you id borrow one from a known good car.

 

[speedsix]

brendy I've already replaced for a new N75F which didn't help. Don't really want to fork out for another.

 

[cordobabrendy]

fair enough though i meant borrow one from someone for 20 mins, go to your next local meet.

 

[speedsix]

I can borrow a C valve of an Ibiza or another F (??) of a LC.

Will let you know how it goes.

Dom

 

[speedsix]

Update. After replacing my boost gauge hose (melted) with stiffer rubber hose, gauge is smoother and 'fluctuations' under load are fairly minimal now so some of the bouncing may have been due to the gauge.

I may experiment with the adjustment screw on my spare N75.

 

[speedsix]

Boost was surging pretty badly in 6th on the motorway so it seems it's completely random the severity.

Tried tweaking the screw on the n75, didn't help

Only other options I have are trying an N75C of an ibiza and another N75F of another cupra.

Tbh I don't think either will help, BOTH my original and replacement N75 work exactly the same, can't both be faulty.

Extremely frustrated

 

[sportbilly]

Any other odd noises when under full boost? Are you loosing pressure anywhere from a loose or split pipe?

Mine was down to a faulty N75, I would try someone else's you could have got a dodgy one ... anything's possible

 

[CupraUK]

I had two faulty N75s before I solved it

 

[speedsix]

I get a loud 'PSSSHHHHHHHH' ~3000rpm just as it hits peak boost but this is due to the air passing through the maf screen so I've been told. I do have a noisy RamAir kit though.

I'll have another look for leaks and try friend's N75.

Dom

 

[speedsix]

It does get progressively better if I turn the boost down, currently on B7.

Is this the problem or should the N75 be able to cope with spikes of ~22psi?

 

[Pabs]

what version of sps are you using? B7 sounds high to me - I'm on the newer sps (v1.1 - only 1 boost scale) and I'm running B6 at the moment.

Revo stage 1 or 2?

 

[speedsix]

v1.1, Revo stage 1.

Overboosts to 22psi, holds 18. I have seen it overboost to 24. Seems to go well without pulling back.

Timing is on 6, run on super 97ron.