boost launch problems....grrrrrrrrr!

[tygraine]

when i try to boost launch, as soon as i get about 6 lbs of boost the motor shuts down for a quick moment, like i shut the key off and turned it back on.
all ignition tune up parts are new, and it did the same thing before i changed them.
one day last week, after rain and wind, i got in, started it up and it ran terrible all the way home. the next day it ran normal again.
the truck runs normal most of the time, just won't build more than 6 lbs up against the brake!
just wondering if anybody has had this problem!
thanks for any input guys!

Dan D.
92 ty 1605

 

[blk00z28]

Re: boost launch problems....grrrrrrrrr!

Hook up datamaster and log a few runs.

 

[SeattleSy#1255]

Re: boost launch problems....grrrrrrrrr!

if you can't build more than 6lbs at launch, it could be a sticky WG assuming it is stock...happens all the time.

one possibiliy of many for the "turn off" is the boost cut off via stock chip.

 

[tygraine]

Re: boost launch problems....grrrrrrrrr!

te-62, atr 3" d/p, atr w/g, ultimate, kb a2a, 9/11 t/q......etc

dave goodhue is going to log some diacom runs with me, i'll go from there.

never ends with these trucks...oh well

 

[gmcturbo]

Re: boost launch problems....grrrrrrrrr!

as soon as i get about 6 lbs of boost the motor shuts down for a quick moment, like i shut the key off and turned it back on.
all ignition tune up parts are new, and it did the same thing before i changed them.
one day last week, after rain and wind, i got in, started it up and it ran terrible all the way home. the next day it ran normal again.
the truck runs normal most of the time, just won't build more than 6 lbs up against the brake!
just wondering if anybody has had this problem!
thanks for any input guys!

Dan D.
92 ty 1605

sounds fuel related

 

[chelo]

Re: boost launch problems....grrrrrrrrr!

how much gas did you have? This has happened to me when fuel is lower than 1/4 tank. Certainly sound fuel like problems.

 

[tygraine]

Re: boost launch problems....grrrrrrrrr!

new walbro, sender, and tank...
would the atr wastegate cause this type of problem? i have never rebuilt it.

 

[dgoodhue]

Re: boost launch problems....grrrrrrrrr!

One thing to clarify is that it cuts out when he is on the brakes trying to build boost. It doesn't cut out when he moving along at WOT and 15 psi.

 

[tygraine]

Re: boost launch problems....grrrrrrrrr!

every time i have launched with near a half tank of gas, the truck has run fine. so fuel problem it was!
thanks for all the input guys. no detonation, back to the track i go.

 

[bezerk]

Re: boost launch problems....grrrrrrrrr!

could be that his stall wouldn't get more that 6PSI

 

[bezerk]

Re: boost launch problems....grrrrrrrrr!

could be that his stall wouldn't get more that 6PSI

:roll: you know what i just meant.

 

[tygraine]

Re: boost launch problems....grrrrrrrrr!

the ty is fixed!!

only during the boost launch, the positive connection on the starter solenoid was hitting the frame under it. solenoid is clocked straight down.
i put the mini starter in 2 years ago, then the truck sat until now.
the motor would surge on and off as soon as i hit 6#'s of boost, just like a rev limiter. it rocked the motor left to right.
when i put the new alternator in i fixed the tie down from the alt. bracket to the frame. next test run, the prob was worse.
new plugs, wires, coil, cap, rotor, module, alternator, belt, timing, tons of test runs......then we put it up on a lift and found the problem. oh well, nice tune up.



Dan D.