I posted this in the motor forum with no replies, I guess I will try here, more knowledge in here anyway.
I have a dead spot at part throttle in my B16. I have no idea why or where it came from, its not just as you apply throttle, and when you go WOT it goes away, but it seems to be kind of where you use it most often.
Feels like its pulling timing out. Any ideas?

Motor is stock exept for intake.

 

Is there a throttle position sensor that could be worn out? I know on the GM's I work on we see this problem occasionally. Pretty easy to check, jst hook up a voltage meter to the output and move the sensor through it's full range of motion. The voltage should change smoothly, if it's not a steady rise and fall you've probably found your problem. Goiod luck!

 

TPS and MAP sensors would be the 1st thing to check. Do you have any kind of engine management or a chipped ECU?

 

Everyhong is bone stock on the motor, ECU, all sensors, everything.
I will check into the TPS and MAP, thanks.

 

when was the last time you checked the plugs/cap/rotor? do you use a honda cap/rotor and NGK plugs? i had a problem once similar to this on my car and it was from a crappy $5 cap and rotor. put honda peices on, no further problems. i've also had this problem when i let the plug gap get too wide. i've always used NGK plugs, but when i was working at honda, 99% of driveability issues were solved by yanking the cheap 99 cent plugs out and putting NGK's in. just some additional ideas.

nate

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by solo-x &raquo;</TD></TR><TR><TD CLASS="quote">when was the last time you checked the plugs/cap/rotor? do you use a honda cap/rotor and NGK plugs? i had a problem once similar to this on my car and it was from a crappy $5 cap and rotor. put honda peices on, no further problems. i've also had this problem when i let the plug gap get too wide. i've always used NGK plugs, but when i was working at honda, 99% of driveability issues were solved by yanking the cheap 99 cent plugs out and putting NGK's in. just some additional ideas.

nate</TD></TR></TABLE>

Good point about the rotor/cap, its stock, and as far as I know never been replaced. The car as almost 100'00 miles on it, so maybe its time. The car has fresh NGK's.

 

Tried new cap and rotor, seems better when warm, but when cold it still has the dead spot, can't tell if its better than before. Strange.

 

I just replaced the 2 O2 sensors on my 328i, and man is it smooth. The car had 122,000 on the original sensors so they were pretty bad, a lot of dead spots and weird throttle response off idle. Now it's all gone. If it's worse when cold, it sounds to me like the oxygen sensors are the next place to look.

Also, on my '00 Si, I had some dead spots when a coil started to go bad due to a wiring issue. Of course, the coil always burned itself out soon afterwards, so you might be having a much more prolonged version of the same problem.

Both directions aren't cheap to deal with, but it sounds like you've already exhausted the cheap and easy ones (did you check TPS/MAP voltages yet?).