Thread: Likely cause of high LTFT's

Lately I've noticed on my aeroforce that my LTFT's are about 6-7 at cruise (~75) on the highway and then when I let off the throttle for a few secs they tend to peg at about 15, neither of which, obviously is good.
I have a couple ideas what may be causing this but I'll just play completely dumb (not that big of a challenge for me) and ask for other's ideas as to what may be happening.
A few weeks ago I installed 1.9 rockers and with getting all the crap out of the way to get the valve covers off and then back on I wonder if I cracked or loosened a vac line or something.
Probably as a direct result of this issue my time at the track this past weekend was about 6/10th's of a sec slower with my new rockers than it was last fall w/o them, 14.4 vs 13.8!

+16.4 LTFT = vacuum leak.

with a vacuum leak youre probably running lean and knocking.

Originally Posted by Bio248

+16.4 LTFT = vacuum leak.

with a vacuum leak youre probably running lean and knocking.

Yeah, that's what I'm guessing but if the leak isn't on my SSIC/blower assembly (hasn't been anyway since PRJ installed it a year ago), what are the usual suspect things/areas?
Car isn't really knocking much though, maybe momentary 1-2 @ WOT but 0 under heavy accelleration.

who knows..just get a can of carb spray and spray around the motor. if the idle changes and revs up then you have found the leak.

Try the typical T-Fittings...they always seem to be going bad due to dry rot. Also check your HVAC lines and TB Fittngs to see if those might be cracked...

Originally Posted by bluegtp91

Try the typical T-Fittings...they always seem to be going bad due to dry rot. Also check your HVAC lines and TB Fittngs to see if those might be cracked...

He has no HVAC lines, but TB fitting is a good thing to try too.

Thanks for the suggestions everyone; I'm gonna grab some spray and check everything I can think of one day real soon, probably this weekend.