Thread: Turbo gurus look; Stumped- help please

if you have issues with vacume, id lean towards mechanical timing/boost leak. i had issues like this for a while with a build i did a few years ago, and was ripping my hair out. it was suggested to me to go back and check, i got all sorts of indignant about it.....long story short, it was off, somehow i didnt set the tensioner right, even though id put doxens of sr's together. check, so you can right it off.....it did exactly what your describing. if you really have swapped ecus around, and dont notice a difference, id have to say look elsewhere for answers. if you really want to check, put a stock ecu, injectors, ad maf combo on it just to see if it will idle/rev.....but anyways.

and actually, i think ashtons right. i thought 550s were closer to 50 pound hrs. i did what your doing with the conversion with a side feed tune and it WORKED just fine, but it was 72 pound hr injectors for a 750 cc tune, i BELIEVE.....its just been a while.

I'm not a guru, not at all, but even I understand that a 550 tune is a bad thing when using 800 injectors. I mean, opening the 550 injectors at 50% is way different than opening the 800s for 50%. 800s on 50% will inject WAY more fuel.

So, essentially, this:

im speaking about maf voltage at idle... im not speaking about open throttle... if mafs working it will rev past 3k

People I am very gracious of the input but I get my tune is off, that's not the point I've been saying the car ran shitty with the injectors ran for the 550 tune. I get what's happening and ill get another map ASAP just to make everyone happy but it won't fix the issue.

My good friend fatonsr20 go through it last night
Ripped harness out and re soldered the all resistors to ground side as that is ideal (heard it did t matter then heard it kinda does)
Swapped out and put his 96# msd top feeds with his rail his maf his ecu with the tune for the setup in my car and the problem persisted.!!!!!!!
Went over all clips wires etc
We over all grounds again
Rechecked timing
Maybe more but I forget..ill see if I can get him to chime in with his input..

Ok everyone so there is 2 pieces to our harnesses, the second piece I was told was called he chassis harness, the piece that goes over the transmission. Apparently the CTS is supposed to ground through that piece correct? So if it isn't grounding then the sensor isn't reading and he car runs just like it is...sounds about right eh?

So I've got another clean chassis harness comin to try out and see if that fixes the issue

please test your maf voltage at idle...

Ok, I'll be honest I didn't read your whole thread because people have literally listed nearly every component in your car.

You need to get your wideband working. Yes you do need a wideband to tell you your car is running to rich to drive because its pretty obvious you are not even sure that is your problem.

With no wideband you are completely in the dark about the state of the engines combustion process.

Spend $150. Get a wideband. Then, verify you are operating under the rich combustion limit. Then you can start replacing everything else. If you have no way to tune the fuel, get a fuel pressure regulator and go from there. Also, KNOW your tune and match pressure and injector size to the tune. Doing anything else is childish.

Just my opinion good sir, and best of luck. I'm sure with all of these good folk we can get you running solid.

Walker

Stop throwing parts at your car and start measuring/troubleshooting. From what I can see you have yet to hook up a Consult cable or similar diagnostic tool, haven't tested your fuel pressure, and haven't done a pressure test on your charge pipes.

C

i dont think he is listening to the forum... cuz he hasnt tested anything in the manner we have requested... i vote for /thread

I have a Wideband, no bung for it. Thanks for the input though.



I've done all three of those things.

My tps is where it's supposed to be and maf as well.

I have an external fpr that reads 3 bar which is 40-42 psi or whatever.