Audi A4 1.8T 1997
So my car does not build boost i push the pedal to the floor and i can hear the turbo spool loud but the boost is not there like it use to before its a huge difference, on top of all this my turbo glows red but only the turbo (hot side) not the turbo manifold the cat at times glows with the turbo even if car is driving slow it well start to glow.

-I check for vacuum leaks but there are 0 i took it all apart.
-all check valves are working normal so its not that
-its not a plug cat because i have a huge 3" turbo back.
-the turbo cooling is working normal there is water and oil and there is no shaft play on the turbo at all.
-injectors work perfect
-coils all work perfect
-spark plugs work perfect all new
-maf is only 2 months old got it new
-no exhaust leaks all gaskets are 2 weeks old
-No CEL codes other than what i already had before but car was working before fine with those codes p1196 p1198 both heater nothing major.
-02 sensors work and read.
-and no boost leaks at all.
-n72 is working fine i even try 2 others
-my bypass bov works normal i can hear it release pressure loud
-all hoses and vacuum lines are new not old.

am basically out of ideas of what it can be :/

 

do you have a boost gauge or a full version of vagcom?

 

no i dont, the car just feels like i have a 1.8L without a turbo at all car runs fine but there is no boost no pull nothing feels like a honda.

 

Maybe shredded the intake wheel? I just had a similar issue on an All-trac, ran 100% fine just felt like there was no turbo. No shaft play, turns out the complete turbine wheel was 100% gone. fins shredded off, but the shaft was still there so it was hard to discover. Have you pulled the turbo and looked at it?

 

only from the front its there , i can hear it spool when am going and when its on idle i hear it normal like i always hear it, i checked the waste gate as well and it works fine open closes and its not lose broken or anything like that.

 

ok so good news! after thinking and seating outside the car thinking and working the brain i came across something!.

It seems i have low low pressure on the fuel rail how do i know? because when i unplug the fuel rail to check i was expecting a squirt loads of gas and pressure all over like any car does, but that was not the case as i unplug nothing came out the gas drip like normal and was not under pressure if anything under minor pressure, i then when to the back to the fuel pump an unplugged a line and bam! squirts of gas and lots of pressure so .. i think i might have a clogged fuel filter i mean the thing has never been change since 1997 the thing looks rusted and like crap.. lol i began to check the injectors and FPR as well and i did find some metal like dirt looking stuff on the FPR screen.

my theory plug fuel filter =starving turbo on gas engine is burning loads of air lacks gas= turbo glows red= which explains why my car shakes and kicks when i try to floor it also i might think it might ping do to bad A/F ratio so the car retards timing since knock sensors hear it which explains the change in tone and note on my engine and exhaust sounds like timing is off.

ill let you all know what happens i well tare down the entire lines if i have to i well make this car work again. but for now ill start with the fuel filter and check the psi on the rail with a gauge before and after to make sure i stand correct.

 

I missed you OP. I thought we had lost you.

 

Okay.

 

well filte rgets here Monday maybe Tuesday, I took some time to check my timing and it was perfect i swap out my FPR for another just to eliminate the possibility of a bad FPR and car dint change much i did how ever find loads of dirt building up on the FPR housing its mix with gas so now i am really positive its the fuel filter cant wait to get it and see what it fixes ill keep posted.

 

ok so its fix Fuel filter was clogged up the *** i could hardly blow through it, boost is back pressure to the rail is back. if any one ever has problems check it it might be that.