Laggy throttle response

[jlevie]

Since you worked on the throttle body, is it possible that the TPS is misadjusted? The idle switch in the TPS should open when the throttle arm is 0.020-0.060" off the throttle stop screw. If the DME thinks that the throttle is still closed because it sees the idle switch closed that might cause a hesitation. Otherwise I'd say it sounds like the AFM.

[skuyler]

oh yeah, i forgot to mention that in the last 7 thousand miles i've put in new"
plugs, wires, distributor, rotor, timing belt, water pump, and cleaned the throttle body...

and if i'm under the hood and pull the throttle cable to rev it, the throttle will open up, slight pause, then it'll rev, so i don't think its the cable

[jlevie]

A bad AFM can cause this.

[JGood]

That's not normal. A throttle cable is a throttle cable. They all swing the throttle body flap open, allowing air in, and the ECU adjusts fuel to compensate. Unless your ECU is from 1910 (read: non-existant), it happens so fast you don't realise it.

Drive by wire cars are different.

Something is wrong with your car. Possibly fuel filter. Give it a tune up. Check the throttle linkage to make sure nobody installed a rubber band in place of the cable.

[skuyler]

I drive a 5 speed '90 325i sedan with 168k on the clock.

I haven't driven any other E30s, but I have driven a few E36s. Now, I'm not sure if it is normal, but if i have my foot off the gas then depress the pedal, there is probably close to a half-second hesitation before the engine realizes I want to rev, and then it picks up like normal. The E36s I've driven (94 325i & 95 318is) get revvin' right off the bat, and that is a much more motivating feeling. Also, once I'm already on the gas, increasing it doesn't have any hesistation. I've read here before that it is just something we have to deal with, but is it really supposed to be this bad? I mean it is always throwing my rev-match downshifts off because of the lag.

I'm not much of a mechanic (see: oblivious), but could it be fuel filter or fuel pump related? I'm having other problems with those right now as well...Would it be worth it to switch to a lightened flywheel (would it change anything)?

Thanks.


Hey, this will be a lot easier, here's some video



Or

http://www.youtube.com/watch?v=1wlJ13I5LZg