2000 S4 boost problem

[Fiyacracka]

Hey guys I've been having problems with my car lately. When I'm in 3rd 4th 5th or 6th gear, if I punch it, the car doesnt want to go anywhere. I have the APR chip (stock, 91, 93). Ive been running it on 93 mode (only putting Sunoco 94). I have no boost gauge. It feels like it gives one big push for a second and then just cuts out.. no turbo noise or anything. I smoke tested the car, with no leaks. Also the check engine light is not on.. any ideas?

[spinny]

Hey guys I've been having problems with my car lately. When I'm in 3rd 4th 5th or 6th gear, if I punch it, the car doesnt want to go anywhere. I have the APR chip (stock, 91, 93). Ive been running it on 93 mode (only putting Sunoco 94). I have no boost gauge. It feels like it gives one big push for a second and then just cuts out.. no turbo noise or anything. I smoke tested the car, with no leaks. Also the check engine light is not on.. any ideas?

Log it, and get a boost gauge.

[s42k5b]

What he said^^^^^

[Fiyacracka]

I picked up a boost gauge, going to wire it tomorrow

[00s4slvr]

apr should be around 15-16 spike to 17-18 so if your boost is at that then your fine

[Fiyacracka]

tbb is fine also the n75 is fine. Now I remember having an issue with a crimped fuel line, which happened when I changed the fuel filter. I am going to try to fix that first. Maybe its not getting enough fuel?

[AudiSportB5S4]

tbb is fine also the n75 is fine. Now I remember having an issue with a crimped fuel line, which happened when I changed the fuel filter. I am going to try to fix that first. Maybe its not getting enough fuel?

could be, I would check that out before you keep bringing your car into the higher RPM range. Did you ever wire up the boost gauge? what's idle vacuum?

[ThirdStrike]

apr should be around 15-16 spike to 17-18 so if your boost is at that then your fine

funny bc my apr chip has always spec'd 20psi and spiked even higher.
why does everyone think apr's software boosts so low?
if youre only seeing 15-16 on your gauge w/ apr u probably have a leak

[00s4slvr]

i never said apr's software was low. There stage 1 chip is about 15-16 psi spike to 17-18.
same with giac, the boost is about 15-16 spike to 17-18 then taper back down to 15-16. The only difference i have seen is giac's boost builds quicker and has a little more pull but its barely noticable.

[Fiyacracka]

i havent wired the gauge yet because I dont have anything to mount it. I want to mount it on the pillar but I dont know where to pick that up from..

[ThirdStrike]

i never said apr's software was low. There stage 1 chip is about 15-16 psi spike to 17-18.
same with giac, the boost is about 15-16 spike to 17-18 then taper back down to 15-16. The only difference i have seen is giac's boost builds quicker and has a little more pull but its barely noticable.

dude run some logs then come back and tell me what the spec boost is
the apr programming i've used always spec'ed 1.3-4 bar.
still betting on a boost leak

[mholme]

why does everyone think apr's software boosts so low?

Probably cause that's what it says on their website I'm sure we have debated this before but 18psi is where my 93 octane program peaks. As far as requested boost? haven't logged in over a year so I don't recall.

if youre only seeing 15-16 on your gauge w/ apr u probably have a leak

I'd have to agree 15-16 psi is not right(assuming we are talking 93oct and above).

[ThirdStrike]

maybe my apr software was just special... i never saw anything less than holding 20 .. and stage 3 is exactly the same.
yah their site does say 1.0 bar.. weird.

[will175]

i havent wired the gauge yet because I dont have anything to mount it. I want to mount it on the pillar but I dont know where to pick that up from..

Like this....Still need to fiberglass it so it looks seamless. But the gauge pod holds itself on the pillar. I just pressed it in the edges of the pillar and it has not moved at all. If you want I can try and look if I still have that gauge box for the part #. Oh and it was for a 52mm but I used a roto zip to make the hole bigger.

[gointoscott]

have you checked it for any codes?

my car was feeling very slugish and it was boosting to 5-7 psi i checked for codes and found one of my egt sensors bad. replaced that andwas boosting normal again.

egt will not always throw a cel light

[Fiyacracka]

there are NO codes what so ever

[00s4slvr]

check the N75 real well because my boost was going nuts and didnt throw any codes. i called up awe tuning and told them how my boost would spike then drop then hold and it was going nuts and they said replace the n75. So i went on ecs tuning and bought their race n75 (it was cheaper than the stock one and they had a deal on it) and so far it fixed my boost.

[Fiyacracka]

but see the thing is, its not going nuts, i barely have any boost at all, at lower rpms i can hear the turbos spool up, but anything after 3000, i get nothing.

[Fiyacracka]

my brother has an s4 too, im going to try his MAF sensor, also the car will go on the hoist in about an hour to fix the fuel line so I'll let you guys know what happens in a couple of hours

[00s4slvr]

keep us posted.

[Fiyacracka]

ok well i fixed the fuel line and I also noticed a collapsed vacuum line. fixed those now the boost is fine, it feels powerful again but it jerks when hitting maximum boost.. thinking its the n75