Very lean low throttle and full rich hi.

[jim90TSi]

Ok car is a 90 awd with 550's and a walbro 190 pump. On my safc settings for low throttle they are as high as 21% Positive correction and my fuel trims are still at 118.7%. On my hi throttle they go negative to arouns -17% and my fuel trims are stuck at 81.2%. The car idles fine, runs pretty good. i have boost set to 14psi and it cuts out pretty bad and feels like it is not pulling as hard as it should. if i bump the boost up to 18psi it runs pretty good until around 4000-5000 rpm, then its like i hit a brick wall and it sputters and sometimes keeps going and sometimes does not (sputter till i let off). Timing is set right at 5* and it has new ngk 6's gapped at .028 with magnecore wires. With the fuel mods i have done it should be rich untouched with the safc but it immediatly runs lean on idle and cruising. O2 voltage is good cruising and idle and also at wot until i hit that wall, which also happens at 14psi ( or stock 11 for that matter.) For what the car has done to it, it feels like it should be alot faster. It is also getting around 13-14mpg granny driving like hell.

Throw me some suggestions

 

[steve]

Oldman should be along shortly to remind you to pressure test your intake to check for boost leaks.

Steve

 

[jim90TSi]

haha i figured that was coming.......I seem to have one very small leak......could it wreak that much havoc?

 

[steve]

From what your describing it sound like you have a lot more than one little leak.

It sounds like your having to add fuel under vacuum and remote fuel under boost. What does that sound like?

Steve

 

[jim90TSi]

Should i test it right on the throttle body elbow also? I heard a small one but couldnt find it....had to rush to work.

 

[psychlow]

You should test it wherever you have to in order to get no leaks, from the turbo all the way to the engine.

I agree that this sounds as if it's your problem.

 

[oldman]

BOOST LEAK TEST!!!

 

[jim90TSi]

Ok boost leak results results.....I found a hole in the metal pipe on the intercooler that goes to the upper intercooler pipe about the size of the tip of a ball point pen, threw some jb weld on that to see if i can get a temp fix till i mount my fmic. Next one confused me, i heard hissing from the throttle body, immediatly thought biss.....nope, i noticed when i bumped the throttle body butterfly the hissing would get louded. If i grabbed whatever you call it the throttle cable hooks into on the outside of the throttle body (brAIN fart) if i move it just right the hissing stops, but it leaks soft closed and gets alot louded wide open.....would that ne throttlebody shaft seals? Also could these 2 miniscule leaks cause all this high end sputtering and bad gas mileage?

 

[steve]

So how long did it hold pressure for without any additional air?

Oh, I'm sorry you still have to replace the throttle body shaft seals before you can start looking for the rest.

Oldman can tell you what he used for the seals on the '90 TB since one side is smaller unlike the 91+ TB shaft.

Once you can hold 20 psi for 30-60 seconds and you still having the same problem we can look at the lower potential causes.

Steve

 

[oldman]

He already hit me up for seals via pm before your post through search, he's not as slow as you think.

 

[steve]

he's not as slow as you think.

I can't help it that I think slow. I'd rather be halffast than halfassed

Steve

 

[oldman]

I meant "he's not as slow as you think he is". You don't think slow, you're just old.

 

[steve]

I don't think he's slow. I just think he doesn't believe us.

Steve

 

[jim90TSi]

No you guys are right....born slow and half pretarted . It's not that I don't believe you guys, my mind just refuses the fact that its such a simple fix for such a large problem. I know it will not cure everything, but it sure will help.