Iamrab

Active Member
Sep 27, 2014
20
0
Hello,

I have a 2001 cupra with the following mods

3" down pipe and full exhaust
Fmic plus hard pipe kit
Air filter
Remapped (unknown mapper)
Forge adjustable actuator
Boost is set at 1 bar

Right so my problems are as follows serious hesitation ,in 2nd gear if I boot it it goes but it struggles badly until 4k then takes off if I then pull 3rd boost drops off to say 10psi or less then pull 4th it might be ok sometimes but most it's just no real power .

I just replaced plugs today with no fix I've 4 nee oem coils coming tomorrow , I've read the ought loads of people's post with all different fixes from split boost pipes to n75 value faulty etc I put the car into a small handheld fault reader and got the following :

P1555-charge pressure maximum
P1556-charge pressure control neg
P1679-epc warning open circuit
P1692-indication light short ground
P0102-mass airflow sensor signal too low

Someone has did the n249 from what I can tell but I'm not 100% certain as any pictures I've looked for on here I can't see

I've cleared all the faults because I've only bought the car so they could have been it in from some time so I'll let you's know if anything comes back over the weekend .the car has plenty if power when it does go right ,the boost issues are very annoying and it's making the car very hard to drive ,when driving the car the smell of fumes from the exhaust is bad to which leads me to Believe that fuel isn't being burn correctly .

Any advice would be greatly appreciate

Thanks
Rab
 
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Have you tried unplugging the MAF sensor to see if it changes? When my MAF went the car ran like **** until about 4k revs then wasnt as bad although still not good.
 
Have you tried unplugging the MAF sensor to see if it changes? When my MAF went the car ran like **** until about 4k revs then wasnt as bad although still not good.

Ok I've not tried that yet I will I know I unplugged it at idle last week and the engine eml light came on and the engine sort of missed slightly . I've attached some pictures of where the dump valve is located because for some reason I also have no negitive vacuum ???



 
Well I tried unplugging the airflow meter and it drives a lot better , I've not been driving it hard due to it from what I understand resets to factory fuel setting ? I've priced up a bosh airflow meter and it's £70 but I want to make sure that defiantly it as I've just doesn't £150 on service items and coil packs

I also moved the dump valve to the hard pipe and it constantly blows open when I floored it it would dump while I had my foot down so I've taken it off and have done away with it for the time being.
 
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When you let go throttle, throttle body closes but there is still boost left, so it goes back into turbo and hits turbo blades and can damage turbo over time...thats why there is a blow off, to vent that boost out
 
It causes the compressor to stall I believe that's what the flutter noise is causing damage to the bearings