car is falling on its face!

[1fstSS]

car is a 90 talon TSi fwd, i just got it. the car runs fantastic at idle, like its doesnt sputter, or shake nothing, youd think it was a brand new motor. but when you start to creat boost, it pulls to about 4-5 grand and falls flat on its face, i mean complete lack of power, i thought maybe it was fuel cut (woulda been the weirdest fuel cut i ever felt) so i added the fuel pump re wire, AEM fuel rail, and FIC 560cc injectors, all tuned in by a MAFT, so at the same time i added a dejon tools uicp, dejon intake pipe, along with the 3 inch gm maf conversion, with a turbo XS type H-RFL. i have a ton of other mods to go on, but i dont want to dive in too far before i figure out whats goin on. any suggestions are appreciated and ill check out all i can!! thanks in advance.

 

[ICGerms]

What does your datalogger say is happening with fuel, timing, knock, etc?

 

[andymoraitis]

The symptom you're describing can be attributed to a number of different causes, but it's best to start with the basics. I would do a correct boost leak test to ensure that the intake tract can hold 20 psi for 30 seconds.

I don't use an MAFT, but I would strongly advise that you follow the advice of the above poster and log a pull in third gear. It could be something as simple as your fuel trims being off. When you intall that many parts, it can be hard to trace down the exact cause, but I would start in those two areas and then move to fuel and spark related issues. It could even be timing being pulled from knock, or the car bogging down from being too rich but everythiing is a guess until you run a boost leak test and post us a log.

Keep us in the loop,

Andy

 

[Staytuned]

Follow what Andy said and also do some routine maintainence on your car. Check plugs, wires, fuel filter, do you have a good fuel pump that you know of? The key is to have a very strong reliable base before you start adding mods to your car. You said it yourself you need to iron this out before you go any further.

 

[1fstSS]

i just did a quick log (mmcd), and my knock revving in nuetral is jumping to 24, timing to 24* i need to do a moving log, but even at idle im sitting at 7* of timing.

 

[andymoraitis]

I've got a quick idea while you're running a log under load. Jack the car up and feel around the back of the block (near the intake mani) for the knock sensor. If you feel lots of goo on the outside, it's shot and needs to be replaced. Staytuned made some great suggestions as well, but having a look at the knock sensor may help you hone in more on what the real issue is. Someone correct me if I'm wrong, but I believe your base timing should be set to 5 degrees. I'd also like to know how much boost you're running and what your fuel pressure is at idle with the vacuum line disconnected.

Drop us a line,

Andy