Bucking/hesitating, 2nd gen 3sgte Options

[Stambo]

I've been cruising around on mr2oc and looking through pages of people having the same problem but never finding a answer to the problem.

It doesn't matter if the engine is hot or cold just driving normally I will experience a hesitation or bucking sensation when just going through the first couple gears.

I change the bkr7e nkg plugs often now. Just threw a new set in. New cap/rotor/wires last fall. Just put a new coil on. Checked timing and its at 10* just like it should be. Used the smoke machine at work and smoked the entire intake system and tightened up any clamps that needed to be tightened on the intercooler piping.

Anyone have any thoughts? Still does the same thing once in awhile.

Next step for me is going to take a lab scope and do a TP sweep and see if there are any bad spots in the tp sensor itself.

This post has been edited by Stambo: Aug 24, 2011 - 11:23 PM

[lagos]

Im having the same problem. It seems its caused by the mechanical timing being off by a tooth or two. So when you set the timing to 10tdc, you are really advancing it causing the bucking to happen during driving.

[Stambo]

Good point. Do you know if one tooth off is 10*? I wonder if i set my base timing to 0 that would make a difference just to confirm that the mechanical timing is off.....

[Stambo]

Found out i needed to plug wires. They were grounding out in the cylinder head through a few pin holes in the plug wire boots.

Mods please close

[Stambo]

Happens again to me now. I've checked grounds everywhere, even cleaned them when they were fine. New plugs gapped to 28. New OEM denso wires, new coil, new fuel filter. Cap and rotor look good, even tested the distributor to the specs given to me from service data. I did the same to the afm also. Ignition timing is perfect at 10degrees.

I also smoked down the entire intake system, including intercooler piping, to make sure i had no vacuum leaks.

It only bucks/misfires right when i tip into boost. Once I hit 5 or so psi the engine picks it's self back up and boosts hard to 6k.

Anyone have any thoughts on this?

[Neon90424]

Det? hot spots?

[Stambo]

detonation your thinking? No idea what would even be causing it. It pulls hard after 5psi which is weird

[Neon90424]

my car pulls hard around 5 psi...because my turbo is dead it wont go past 8 psi but it still pulls

[Stambo]

mine will pull all the way to 14psi