valve float

[buickpower]

Ok, I've been having a leaning out problem on top end, but the car now seems to be holding fuel pressure now, yet still cutting right out. The thing is, it still seems lean but i wonder if this is compounded with another (valvetrain??) problem. Reason being because if slowly depress the pedal to about 3/4 or so, it will build full boost (15psi) and will steadily pull, despite being lean. But if I get into it hard and it downshifts and revs way up, after a fraction of a second or so of staying in it, it acts like hitting a wall or fuel cutoff. Does this have anything to do with valve float? I have read about it but never experienced it. Does the motor stay at rather high rpm but just lose power when the valves float? or does it cut right out like mine does? I only wondered about float because I have a rather noisy valvetrain and was wondering if my lifter preload was incorrect.

 

[frankg]

Might have a bad TPS sensor or it may not be set to the proper counts?? Valve float will just stop pulling hard and miss. Frank

 

[Mike Licht]

Sounds more like spark blow out to me
Mike

 

[buickpower]

after making some pulls today on backroads, i would definitely say it seems to act like a spark issue, as fuel pressure was not dropping off. still lean as hell though, even on the max translator setting.

 

[buickpower]

another question, if i had an exhaust leak under boost, would it show up as high blm's at WOT, or would they just lock on a certain number as per the chip burner's design?

 

[frankg]

Is it shutting down like going to zero throttle or missing and/or popping? If it's a miss might be weak spark or valve springs, plug gap too wide. I thought you meant it was like shutting off???? Frank

 

[buickpower]

well it was like going to zero throttle. i found a burned plug wire and that helped it a little, but still reading crazy lean. I find that if I roll into the throttle gradually it will allow me to go wide open eventually on ocassion without cutting out. However if I floor it and it downshifts and boost shoots up, it will still cut out.

would valve float be reading as a lean condition, because the valves are staying open too much, especially with boost pressure behind them??

 

[Russ Merritt]

Have you tried to richen it with the chip yet?

Put the translator back to zero on the WOT and try richening it with the chip if you haven't tried it yet. I find the chip has way more control on WOT fueling.

Also your base setting, is that on the correct size MAF you have? I've seen that a bunch of times also, people put it on the 3.5 setting instead of the 3" sensor they have.........

 

[buickpower]

I asked eric about it, and my chip is a couple years old so it is non-adjustable. The translator is on the base setting 3 for a 3" LT1 sensor (I measured it) so I think that should be ok.

 

[Russ Merritt]

Get an updated chip.

 

[buickpower]

I'll do that as soon as I am able. Starting to wonder about my O2 sensor, it will record like 582 millivolts with 0.0 knock, but the plugs are reading white so maybe not.

 

[Paul Clark]

I'm fighting the same problem. It started after the install of a new tranny.
I was thinking it was something in the transmission or possibly TV cable adjustment because it happens at WOT, but I'm open to any and all ideas.
Does your car seem to get "confused" before the 2-3 shift?
Is it possible to have too little or too much power for a transmission, or could the rev limiter be bogging down the engine before the shift?
Too much alky? (no backfiring)
Let me know what you find out. It's giving me a headache.
Thanks
Paul

 

[buickpower]

Paul, thats a possibility as I also have transmission problems, can't seem to get the tv cable right which is why i'll be getting a new one. Mine stacks the shifts and also seems to pause before upshifting. Guess the tranny can't handle all the power from this hotair brute LOL.

 

[Paul Clark]

Try this. It "almost" fixed my problems today.
Do the factory re-set thing on the TV cable.
Then soften it up (push towards the radiator) one or two clicks.
Increase your FP 1 or 2 pounds and see if things get better.
Hope so.