Ibiza cupra odd limp mode and overboost

Ziggydan

Guest
Hi all,

My first topic so apologies if it is in the wrong place, i have a fault on my 2001 ibiza cupra and i cant work it out. Ive recently changed the fuel pressure regulator to one off an early vr6 corrado in a small attempt to rich my mixture up as its running lean at the top. After changing this i cleared all dtc's so the adaption values for fuel trim would start fresh.

Now a problem has arisen that i used to have but seemed to resolve itself over a long period of time. I keep getting the following:

17693 charge pressure maximum limit exceeded
P1555-35-00
16795 Secondary air injection system:incorrect flow detected.
P0411-35-00
This one doesnt bother me because i removed the secondary air system.

17536 Fuel trim bank 1 (mult) system too lean
P1128-35-10. Intermittent
Still running lean but was a problem previously

I dont understand the overboost problem, it will run about 11psi whereas previously it was happy with 15-16psi?

I dont understand how limp mode is controlling my boost down to 4 psi, because i have removed the n112 & n249 solenoids, i have also removed all plumbing from the n75 and am using a greddy profec 2 boost controller?

Is there anything in vcds adaption that i can change to alter the boost limit?

Why did my ecu previously become happy with 15-16psi after a few weeks when now it wont accept anything over 11?

I also have a problem with my oil light flashing and beeping but i have cleaned pump pickup, replaced pump, replaced oil and filter, and replaced oil pressure switch?

And my final problem is my rev meter, it jumps about but most of the time bounces between 0-500 revs and frequently sits on 0. Vcds records the correct revs and since my ignition timing is ok then i dont think its a sensor issue, also if i use vcds to run basic tests it moves the rev needle nice and smoothly and stops precisely at full deflection, zero and holds fine in the centre so vcds doesnt indicate its the clock either?


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ibizacupra

Jack-RIP my little Friend
Jul 25, 2001
31,333
19
glos.uk
ecu will close throttle also if its unhappy and you've removed the rest of its control

how do you know its running lean?? fault code yes but thats only updating on cruise/idle so more likely a vac leak from under manifold probably the pcv pipes

narrow band ecu on ibiza.. lambda is only active for fuel trims on idle and cruise, not under boost

Sounds like you have "ibiza" wiring issues, resulting in random sh1t happening.
 

Ziggydan

Guest
Well i did have a thought about ecu closing throttle to reduce power and limit boost but i wasnt sure if that would cause boost spike.

On the lean side i thought that because the fault indicated multiplicative fuel trim that was non idle (atleast that is what vcds fuel trim page says)

Ill have to have a look at the electrics for the fault light and dodgy rev counter.

Still no idea why now it will limp if boost goes over 11psi where previously it was fine with 15/16?


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Ziggydan

Guest
I reads about 120g/s max, i thought this was a little bit low, got a new bosch one and it ran terribly so i took it back. Unfortunately i dont know what maf is on it because i cant see a part number and the lad i bought the car off said he had changed it for a different one :s


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Ziggydan

Guest
Thanks for the responses by the way :)


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ibizacupra

Jack-RIP my little Friend
Jul 25, 2001
31,333
19
glos.uk
the sensor element inside should end 040 if correct sensor.. (narrow band maf) as opposed 049 which would be the wrong sensor (wideband car)
 

Ziggydan

Guest
Just checked the old order email and the one i took back ended in 040, not sure what mine ends in, ill try and look tommorow.


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Ziggydan

Guest
Right finally got round to taking my maf out and it has nothing like either of those, on one side is pbt-gf-30 on the other side is 07 10 07, not a clue what this, the housing is magnetti marelli so i dont think its original :/


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Ziggydan

Guest
The one i got from eurocarparts was bosch and it ran terrible :s


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