Hello everyone,
My car 1990 Accord Sedan Auto. Every thing is stock except for the stereo system. The car is well maintained by myself since I got it in 2008. Here's a glimpse of it. The plugs are NGK G-power, wires are new Denso, cap and rotor are OEM, EGR plugs cleaned 2 years ago and problem existed since I got it through today and wonder what is it. It's not as bad lately but I do notice it.
Basically when I go on the freeway accelerating, every thing going smooth, until I get from 3rd to 4th gear. The Tach meter between 2400-2600rpm, and before hitting 3000rmp, I notice the meter hesitate and drop about 100-200rpm and the meter flick right back up to normal. It's just a slight instant. I barely notice the car hesitate a little also. I wonder if it's some thing any one has experience and has a fix for it?
I can't think of any thing right now, possibly the igniter or the coil? But if those 2 items are bad wouldn't symptoms be more consistent throughout.

Thanks for any idea or help.

 

Since it's happening only between 3rd and 4th the only thing I could think of is something with the tranny.

 

Do you think it's the igniter since the tach is tie to it? I have tested sparks and Helm's igniter test method, all ok.
I know the transmission is good. Do you think it's the solenoids? Maybe it needs cleaning? I don't think it's the VSS as I replaced that with a new OEM part not too long ago and my speedometer and every thing else works smoothly.
Thanks.