I have a problem with my mk4 golf GTI 1.8T. The car has just had an 80,000 mile service. The problem is difficult to describe correctly, but basically when accelerating hard, the power is lost (as if I were taking my foot off the pedal) and then will come back gradually.
What could it be?
I have change the fuel filter and i´m thinking it could be the injectors maybe there dirty but relly don't no
Its the MAF when I was ready to cleaned I figure that was missing a metal vend like (U) so any way I cleaned and the car was working fine about 5 min and then start the problem again I try all the way accelerator all the way in and the car didn't respond, by the way i´m going to clean the Throttle Body I thought will be better to have it clean after a new MAF.
there are no codes for a faulty MAF, only a code if you disconnect it, you will never get a code that says "maf reading beyond XXXX"
if the car runs like crap long enuf you will get
system one bank too leam
random multi misfire
and then 4 more codes for random multi misfires on all 4 cylinders, so in total you can get 6 codes, and not a one of them will mention the MAF
what is basically happening is the maf is reading an incorrect airflow, the map is reading a different #, so the car goes WTF, its not sure what is happening so it limits boost, leans the mixture to prevent damage to the CAT and pulls so much timing that you get the misfire codes
could be an intermittantly bad ignition coil (Ive personally had this problem) or it could be pulling a lot of timing for some reason. It could be seeing really high intake temps, which would certainly cause the problem your having. Or it could be boosting high and recieving much colder air then its used to, causing it to lean out and pull timing.
its going to be hard to know for sure until something breaks, you start replacing parts, or you data log it with vcds.
2012 United Graying GTI
//Carbonio intake stg.1&2 // Apr K04 Turbo & Software //Apr Intercooler // Eurojet 3" Tbe // H&R Ultra Lows // VWR short shift // Southbend stg 2 endurance clutch // BBS LM's //Euro Switch // Red Footwell lighting // Autotech insert // Rear Wiper delete //Podi boost gauge Vag - com tweaks courtesy of mike Wolfsburg Gli
Its not your coil packs, or your injectors.
Ive had my 20th for 6 years now.. And let me tell u, i know just about anything that this car could have problems with.
If your losing power, on acceleration, aka going into a "limp Mode" its either your N75 vavle, or you have a boost leak somewere.
Most likely though i think its the N75 Vavle.
sounds like fuel to me, but if it was injectors you'd have a fault. or boost leak.
My 2003 jetta started to sputter under heavy acceleration on the way home from work today. Its very mild in 1st gear, but you really notice it in every other gear (2nd-5th). It almost feels as if the traction control is kicking in but the light is not flashing and it does it regardless, traction control on/off. the Check engine Light has not come on at all. Almost seems like a loss of boost or ecm controlled delay in the timing. I unplugged the pressure control valve (n75) and the shutter was gone but the car was definitely under powered. The car has 85,000 miles, I replaced the Timing belt at 83,000miles and is stock other than a blow off valve. (just sounds cool ).
I am thinking its the n75 pressure valve, and from what I have read they fail often. But before spending $55 on one I am wondering if there is any way to test it to make sure that is my problem?
Any Help would be awsome
Last edited by AimlessB; 03-14-2012 at 12:29 AM.
Just bought my 02 GTI recently and same symptoms. I would step on the gas and it would sputter and flutter around 3k rpm with no boost. Found that the rubber hose (about 2.5" diameter) from the turbo (engine area, assuming) has popped off the plastic U shaped pipe going into the passenger side of the FMIC slightly and was leaking air. When I accelerate it sounded like the wind was blowing more on my passenger side compared to drivers side with the windows open. Reattached the plastic hose with a fitted metal clamp ring and fixed the problem.
Theres oil inside that rubber tube going into the FMIC, is that an issue that i have to look into?
You could get rid of that oil build up by adding a catch can in line to that connection, before the plastic hockey puck valve.