Track car issues - help required

[S3 TAM]

Morning All,

As some of you know me and bigcheese have been working on a track car this past year.
It’s a Seat Ibiza Cupra. It’s finally back together but having a couple of issue’s at the min and need some assistance.

On a test drive it was boosting fine, all of a sudden boost drops off. Running on actuator 5 PSI.
Thought not a problem N75 died, limped home replaced N75 with new one still no joy. Scanned with VC. Fault code N75 related. So we checked the wiring and found a small split in the plastic coating near the N75 connecter.

1. Would this be enough to cause issues?

The split is too close to the connecter to repair so I will need to source a new connecter.
I noticed the EVAP canister connecter is the same so I’m thinking to cut the connector from there are replace with a resistor.

What do you guys think? Is this gonna be ok or should we get a connecter from somewhere else.

On to the next issue BRAKES…..

We replaced discs and pad’s all round, removed all the callipers and changed brake lines.
We have to replace one of the HARD brake lines from the ABS unit as we f***d it up when trying to remove the old lines.

We bled the system flushed about 2Ltr of fluid through but the pedal is real soft /spongy.

Do we have to bleed the abs unit? If so how do I do it with vag com? Whats the process?


Cheers in advance....

 

[StaceyS3]

Alright mate hows it going

The n75 wiring could be at fault if it's managing to short to ground or across the two cores? Also a possibility could be you've got a broken core somewhere?
Pending what ecu you've got could be MAF related as Jay was having on off boost issues which turned out to be his MAF failing?

With the brakes I had a simular issue when had the rear Calipers off and managed to drain most of the fluid in the system, I did have to use a pressure bleeder as well as pumping the pedal (slowly) as managed to get air in there, it took me 3-4 attempts at bleeding it over a couple of months (as well as a garage for my own sanity) after it had been done it would be alright and gradually get worse which always seemed after the abs cutting in, knowing what I know now would have used vagcom to bleed the abs pump but at the time didn't know to much and hadn't discovered this forum

 

[badger5]

pressure bleed until it works.. it can take a few goes.

boost/n75 can be cycled from vagcom... ty that and listen for clicking. its under engine and output tests

 

[S3 TAM]

Cheers for the info.

Do you think I will have to bleed the abs unit as I've have the line off of it?

 

[badger5]

perhaps cycle it, but pressure bleed should encourage the air out eventually

 

[Westy]

I did see a guide either on here or the Ross-tech website for using VCDS to do the abs.

 

[<tuffty/>]

Ross-Tech: VAG-COM: ABS Brake Pump Bleeding

<tuffty/>

 

[Prawn]

I had the same boost issues Tam, N75 intermittent fault code. All looked well.

On stripping the wiring back, it had cracked and parted, yet under normal conditions the ends touched and contact was made and we had boost. Under full throttle the vibration / engine movement was just enough to pull the wires and lose touch. No boost.

Have you bled the master cylinder as well for the brakes?

By big cheese, do you mean Westy?

 

[Westy]

By big cheese, do you mean Westy?

Lol no not me. It's his mate Pete. His name on ASN is Big Cheese.

 

[Prawn]

oh right, ACTUAL big cheese!

You know, I just thought you were the big cheese around those parts westicles....

 

[Westy]

oh right, ACTUAL big cheese!

You know, I just thought you were the big cheese around those parts westicles....

This guy is bigger and cheesier then me

 

[S3 TAM]

Again cheers for the input guys.

Might seem silly to some but where is the bleed nipple for the master cylinder. Ive had a look around and cant see it on there. When it came to topping up the fluid there was none in there.

 

[superkarl]

This guy is bigger and cheesier then me

i dont believe thats possible

 

[superkarl]

Again cheers for the input guys.

Might seem silly to some but where is the bleed nipple for the master cylinder. Ive had a look around and cant see it on there. When it came to topping up the fluid there was none in there.

its in there somewhere tam, 2 nipples, they are fairly tucked away and an **** to get to.
ooo, hang on, its an ibiza, hmmmm.

 

[s3dave]

2 nipples, they are fairly tucked away and an **** to get .

Disgusting Brute.....

 

[S3 TAM]

Ok

Ecu is now clear of faults.

Still running on actuator......

Rewired N75 seems to be working via vagcom.

Did lots of logging. Noticed 12 degrees on all 4 as soon as u touched the pedal. Knock sensor was loose. There was a code for that. Now clear.

At a bit of a loss as there are no codes now to diagnose the issue. seems to be running better but still only 4-5 psi.

Forgot to bring the logs to work!

Anyone got any ideas. Could the turbo be shagged?

Its running ko3s stage 1, intercooler, 008p, full turbo back milltek, ie rods and so on....

Bhp 156
Ftlb 163

Stats via block 115 last night.


Edit MAF seems ok as well.

 

[Westy]

Tam, do you get a code by running the car with the N75 unplugged? It definitely sounds like the N75 is completely dead now. I cant think of any other reason why it would only run on actuator when is was able to boost more before you fiddled with the N75

 

[S3 TAM]

Rewired it last night. Seems to work when u do output tests. We have 2 brand new N75's. but the fault codes have gone now.

Its strange it feels like the remap has disappear because the car seems to run fine. Just lack of boost.

I thought that the ecu was fried but it seems to work ok when using vagcom.

 

[S3 TAM]

Heres a few pics

 

[S3 TAM]

I checked n75 duty cycle.

It was 13.7% - 88.9%

Which i think is ok

 

[Westy]

You've definitely got the N75 pipework the right way round? If you unplug the N75 and start the car you should get a VCDS code about it. Be nice to see if this is still actually registering.

Just trying to throw some ideas out there.

 

[badger5]

Rewired it last night. Seems to work when u do output tests. We have 2 brand new N75's. but the fault codes have gone now.

Its strange it feels like the remap has disappear because the car seems to run fine. Just lack of boost.

I thought that the ecu was fried but it seems to work ok when using vagcom.

what map is on the car?

 

[S3 TAM]

The car was bought with a remapped ecu.

looking through the receipts this place did it The Phirm they do revo maps but it does not specify what remap was done!!! just stage 1.

 

[badger5]

possible its switched to stock if revo... anyone you know have an sps unit?

 

[S3 TAM]

Yeah i have one, i'll give it a go tonight any recommended settings?

 

[Westy]

Yeah i have one, i'll give it a go tonight any recommended settings?

9, 9, 9

 

[S3 TAM]

ohh yeah

 

[badger5]

boost 6 timing 4 for starters

 

[S3 TAM]

You read my mind!

Will post up results

 

[S3 TAM]

Ok sps settings 6-4 hasn't worked.

Really dont know what to do now.

Unplug n75 like westy suggested error came up.

Ahhhhh

 

[Westy]

Ok sps settings 6-4 hasn't worked.

Really dont know what to do now.

Unplug n75 like westy suggested error came up.

Ahhhhh

So it's detecting that the N75 isn't plugged in which is good as it suggests your wiring is ok. Have you tried one of your other N75s yet? Hoses are on the right way yeah?

 

[S3 TAM]

Success

We have boost.

We did the following...

• removed boost hoses and refitted
• removed and cleaned MAF
• swap the connector from the evap canister to the N75 valve. i.e. rewired both.
• removed and reseated ecu connectors
• unplugged and re-plugged any connector visible from lambda to AIT sensor.

not sure what cured it...

Don't think it has a Revo map on it as changing settings didn't change boost/performance.

Did notice it is pulling lots of timing check out the logs/graphs

 

[Westy]

Good work bud. Late night mechanics FTW.

That is some mad timing pull! Also the "actual" boost is doing strange things! Up and down like a tarts draws! Think Pete needs to get it remapped.

 

[S3 TAM]

I know the actual boost is mental.

not really sure what to do about the timing pull as unable to change anything because its not a Revo map.

has anyone got any ideas.

could I change the degrees in unisettings or is that not advisable?

 

[Westy]

You could scale down the boost in unisettings. Remember I had to do that to my car once the new K04 was fitted? Should hopefully bring the timing down a bit. Other alternative is to run on actuator pressure till its remapped.

 

[S3 TAM]

Someone is selling a revo mapped ECU from another seat ibiza cupra.

if bigcheesey gets it will it be a straight swap. i.e. don't have to worry about immobilizer?

or will it have to be recoded if so is it poss with vag com

 

[Westy]

I don't think it's as easy as a swap. I'm sure the ECU is coded to the car dials and IMO but I'm sure someone will be able to tell you for definite.

 

[jojo]

Someone is selling a revo mapped ECU from another seat ibiza cupra.

if bigcheesey gets it will it be a straight swap. i.e. don't have to worry about immobilizer?

or will it have to be recoded if so is it poss with vag com

If it's wired up the same way as Audi's, which I presume it is, then it's not a straight forward swop, the immobiliser would be a stumbling block.

 

[S3 TAM]

yep your both right just been reading about it.

basically it's cheaper to go and get a new map i.e. revo/bill

with out the correct gear and knowledge £££££££

 

[badger5]

Someone is selling a revo mapped ECU from another seat ibiza cupra.

if bigcheesey gets it will it be a straight swap. i.e. don't have to worry about immobilizer?

or will it have to be recoded if so is it poss with vag com

ibiza just needs to be coded to clocks in vagcom
simple 2min job