Boost/Fuel/Timing/Compression issue(s)

[MDCmotorsports]

Well not sure where to start.

I can say this, newbs and guess masters need not apply.

Im running the lex 550 combo with all the fuel mods (pump, reg, etc etc).

Im not sure whats going on, but here goes:

When I go past 9 or so psi the "pull" through the RPM range is horrible. The engine and turbo make tons of go fast noises, but the car just doesn't pull.

-Boost leak?
Nope. Pressurised the boost system and no leaks.

-Dead cyl(s)?
Nope. 170 accross the board.

-Bad plugs?
Nope. All at .030 and some what clean. Installed new ones just to be safe.

-Bad BOV?
Nope. Even switched to another KNOWN working BOV and still the same result.

I really don't know where else to look. I thought possibly the TPS. So I switched to a FACTORY throttle body that I know has never been monkied with.

Now all the car does is backfire like mad, and the "pulling" issue is worse.

I also ispected the clutch and all of its components and all apears to be working correctly.

Any help on why the car is doing this and or what its doing would greatly be appreciated.

:biglaugh:

 

[GrimJack]

Ok, I hate to ask the painfully obvious... but you checked for codes? And you've checked base timing? Do you have a wideband O2?

I'd check for the timing belt having skipped a tooth... knock sensor wiring... that's what I can think of off the top of my head that might cause this.

 

[malloynx]

if wonder if the car is pulling timing. what is the vf output doin at idle and cruise

 

[MDCmotorsports]

Grim: That was one of the first thing I checked. 10 deg base timing with the jumper in.

Will check the knock sensors tomorrow....

The only code that I had was #11. No codes now after reset.

Will also check the timing belt.

Im running a stock o2.


Malloynx: I will check that tomorrow.

 

[tubbie]

dieing afm??

 

[MDCmotorsports]

Tubbie: Nope. Thanks though.

 

[Mr. Y]

ha-ha-ha!!!
Welcome to our club, man:
http://www.supramania.com/forums/showthread.php?t=7270
http://www.supraforums.com/forum/showthread.php?t=317711
http://www.supraforums.com/forum/showthread.php?t=320241

I have no ideas, except try to fool ECU (remove KS from block, and put em in the glovebox ;-) or rewire and re-adjust CPS (make gaps less).

 

[MDCmotorsports]

Hmmm sounds to me like Steveangst is having the same problema. He just described to me too about my plugs. The car is known to be running rich... looks like a diesel down the road at WOT, but yet the plugs are white???

Hmmm time to try some race gas I guess.

Im guessing the gas is bad, so the thing is knocking to the knock sensors, and the car is pulling the timing.

 

[lagged]

check that you havent jumped a tooth on the timing belt.

read your plugs.

 

[MDCmotorsports]

Well it wasn't timing, fuel, or the plugs.

Dying turbo.

Damn thing let go this afternoon.

Don't know why yet, havent' taken it apart.

But today I was driving, and the boost went 1,2,3,4,5,6,7,8,9....... 9 1/4...... 9 2/3........ 9 9/10......... 10

I had the boost controller set on 15.

It won't boost at all now, and sounds like nails on a chalkboard.

The compressor wheel still spins fine, but it has massive front to back play.

Oh joy.

Turbo pullin time... or Holset install time??? Hmmm.....

 

[antman]

was it stock?

 

[MDCmotorsports]

No and it wasn't the turbo's fault or the way I rebuilt it. Turns out the BOV was FROZEN shut due to water and the weather going from 60 F to 22 F in 8 hours.

 

[figgie]

ouch

that is painful

oh well.. what where you doing boosting in 22 degree F weather though hehe

 

[MDCmotorsports]

what where you doing boosting in 22 degree F weather though hehe

Having fun. What else?

22f on 16psi is like race gas at 20psi.

:biglaugh:

 

[shaeff]

i love boosting in winter. :love:

-shaeff

 

[antman]

lol..good shit man! is your throttlebody in any danger?