surging at any rpm while driving
 

Hello, I cleaned the egr plenum and ports on my 96 accord ex, auto, 2.2 vtec. This got rid of the misfire and cleared the CEL. That was two weeks ago, has been running well until today. Now there is a bad surging at any rpm while driving, you can see the rpm fluctuate around 500 rpm. The idle is fine, no surging that I can see. I have searched for this but have come up with other variations of my problem, mostly a surge at idle. There is no check engine light. The car has around 180k miles.

Suggest checking your installation of fuel injectors to the intake manifold and fuel rail to make sure all orings are in place and sealing. Leaking FI might cause this problem, and not show up at idle.

Check all your EGR vacuum line connections. Check EGR valve movement. EGR valve sticking open might cause this problem. I don't know if that would set an EGR code, but it should cause idle problems if stuck open at idle.

good luck

I did check the rail/injectors and everything looks good, all in place and no leaks. The Egr was moving, by hand, when I had the plenum apart for cleaning. No surging at idle and no codes. Possible fuel filter issues?

I'll assume you "feel" the surge in the engine and not just see it on the tach?

You said something about the fuel filter, are the other maint items good? Cap, rotor, wires, plugs.

The cap, rotor, plugs and wires are new a couple thousand miles ago.I have a fuel filter on hand and will change it before I drive the car again. The surge is a definate "buck" when driving at all speeds. The rpm will drop and rise rapidly- around 500 at a time.

Just to rule it out, how about checking the adjustment of the transmission cable from the throttle body down to the trans. It might be the torque converter locking & unlocking.

okay, I will check that out too. Thinking about it now, when the "techs" at the dealership put the new throttle body on, the cable might be not adjusted right. thanks Jim

just a quick update- checked the tranny downshift cable tonight after work and the downshift lever starts to move immediately in unison with the throttle. so next I will change the fuel filter because I have one on hand. I have my doubts that it is what is causing the surging. Could the EGR or IACV be cycling causing this?

I have occasionally seen posts of mysterious drivability symptoms being resolved by a new O2 sensor. If yours is over 80K miles, you might consider this option. You can find a new O2 sensor at a reasonable price; rockauto, ebay, etc.

good luck

Ok, I will add it to the list! thanks:)