if any of you have read any of my previous posts, i found out what the problem was with the hp loss......the intake was attached too far to the maf blocking airflow.

now for the next problem:

after fixing the air flow problem, i proceeded to install my turbo. i had no problems with the way that it ran until i put on the turbo. it is not yet routed to my intake for boost yet. i have the oil lines and exhaust all hooked up properly. went to go start it and it ran really really rich and stalled out on me. i went to start it and it acted like it was flooded. finally got it started and then hit the highway then at steady driving speed the car slowly started to lose speed. i let off of the throttle and the car died. i got it to start a couple of times but then it dies. when i start it and it does decide to run it runs great (with the clutch pedal pressed in)......let off the clutch pedal and it drops rpm's and then dies and acts like it is flooded then wont start.

here is a list of the parts on the car:

S4 turbo, manifold
S5 TII tps
S5 TII upper and lower intakes
S5 TII fuel pump
S5 N/A fuel injectors
S5 TII fuel rails
S5 N/A maf
S5 N/A pressure/boost sensor
SAFCII unprogrammed

 

So you have the turbo bolted on, but the inlet and outlet of the compressor are connected to nothing? I hope the wastegate line is hooked up somewhere on the intake manifold (or propped open all the time) or you're going to over-spin that turbo & fry the bearings.

Is the ECU TII or NA? If TII, you need to get rid of the NA AFM and MAP sensor and put in TII injectors. You can get away with the TPS not matching, but everything else needs to be the same.

If things aren't mixed up, a vacuum leak also fits your problems.

 

the wastegate is propped open. the injectors are n/a, the map is n/a, the maf is n/a, and the ecu is n/a. i just got home from trying to get it home and it fired right up and ran good. after driving it for about 3-5 minutes, it didnt want to respond to the throttle. i put it in neutral and tried to give it throttle but it did "nothing". stalled out and couldnt get it started again. when try to start it, the engine turns over but then when i turn the key off, it feels like the engine comes to a halt. after it cools down for a couple of hours, it will start up and do the same thing all over again.

no vacuum leaks, no fuel leaks, all sensors are working correctly. i do have a TII pump in it but i never tested it to see if it is working properly. also, i dont even know if the float is reading the fuel level correctly. could it be that the tank is empty but showing that i have fuel, therefore, it will drive for about a mile then die on me?

 

Who put the motor together? Any strange sounds when the clutch pedal is pressed in? If it runs differently with the clutch pressed it COULD be crushed thrust bearings...the eccentric movies forward and changes timing when they are missing. Check the end-play of the eccentric to eliminate the possibility of this.

 

even if the thrust bearing is fried it shouldnt cause the engine to stall in neutral. it never did this with the n/a setup on it.

 

the car is doing to same thing after i went back to try to get it home. like before, it fired right up, got two miles down the road, after the engine warmed up a bit, it started losing hp and shut down on me. the turbo is spinning freely but it is getting really hot. i dont know what to do.

 

Disconnect the S-AFC and see if the car works.

Have the injectors been cleaned and flow tested?

 

aaron,

i had the injectors rebuilt and new seals. i will try the safc thing and let you know how it works. thanks!

 

i will update around 6 or 7pm after i tinker with it.

 

This is starting to sound like limp mode. Is the CEL light coming on? You should probably check for and codes even if it's not. I put a link in the FAQ engine section.

 

no, i had it in limp mode before and this is nothing like that. i had a friend shoot me some advice:

he asked me what my oil pressure was at and how i had the turbo oil feed line routed. i said to him that my oil pressure has dropped pretty low and that the oil feed line is routed directly into a t-fitting that is in the oil pressure sending unit hole on the side of the motor. he said that it sounds like the engine is starving of oil and all the pressure is going to the turbo instead.

does this sound about right given the way it is acting ( cold start runs alright, gets warm starts running like **** gets to normal temp and then wants to shut off and not start. when i go to start it, it cranks then i let off the key and the engine instantly stops)

 

No running a t from the oil pressure sending does not starve the motor. I ran a t for my feed line from the oil pressure sending unit as well for a while.
Is your ect good do you know? Are you running tii intake or n.a?

 

is the tps in the correct place?
S5 N/A and TII tps are the same, but if the placement on the tps bracket is wrong, it might shut the car off when warmed up.

 

it is acting like it is starving from something.......fuel,air,spark?

i checked the spark and the coils are firing correctly

the timing is dead on

it has airflow and the maf is working

fuel: it is getting fuel. when i does decide to start, it runs rough and acts like it is either getting too much or not enough. i am running stock n/a injectors still.

tps is working good

ecu is working like it should

map sensor is working

fuel pump is working (fd)

good fuel filter

turbo is spinning freely

engine has oil pressure

grounds are good

exhaust is flowing properly (has stock front converter hollowed out)

intakes are not leaking

What else could it be?

 

It sounds to me like u got a bad maf sensor, try disconnecting it an turning on the car see if there is no change on how is acting, when mine went bad on my S5 It would barely start, and when it was cold it would drive but felt like the engine had no power, and when it warmed up the car would completely shut off if I hit the gas I had to barely tap the gas to keep the car moving, and when it was warm if I tried to start it it would cut on and shut off u should try changing ur maf, see if that helps

 

i will see it it helps, but, i have a TII and an N/A and both installed have the same impression on the car. i will try though.....

 

for those or you who have read this posting and tried to help me.....thank you.

i found the problem:

completely fouled spark plugs that were not firing AT ALL

wire from ecu came undone.

 

back to the drawing board..............

i thought i got the kinks out, but it still is having problems.

getting spark...getting fuel. it will start up and run sometimes but will not run any lower than 1200rpms or it dies and wont start for ****. when it stalls, it takes forever to get it started again. when it does run, it runs a little rough and acts like it is getting too much fuel. when it dies, it floods really bad.

i have all TII parts installed fuel pump, afm, tps, upper lower intakes (lower intake is 4 port customized to fit the 6 port engine), pressure/boost sensor, fuel rails, fuel injectors, ecu

the only things that are n/a still in the car is the wire harness. could the wire harness be the problem?

i actually put all n/a stuff back in the car and it does the same thing.

how do i know if the injectors are low or high imp? and how do i know if i need low or high imp injectors?

 

oh yeah, i bought the TII injectors from somebody within this forum. they worked fine when i had them installed on the n/a setup, no problems at all.