Hello! This is my first post to this forum. I am a regular at www.powerstroke.org (ford's diesel forum) and we just bought an 01 Accord. It is a 4 w/ the f23a1 VTEC engine. The transmission is stock. We have had this car for about a month now.

A couple of weeks ago it was about 20 degrees out, and when I started the car, it fired right up, but the idle immediately went down to about 500 RPMs. When it went this low the car shook a good bit and when I triped to put it into reverse, it shook even worse. I scanned the codes and it reported multiple misfires and a faulty o2 sensor. I replaced all of the spark plugs, wires, distributor cap, rotor button, and the o2 sensor. However, the same problem still exists, but it is not throwing a code anymore. Can anyone recommend what I should do next to cure the low idle shudders on cold mornings? Thanks!

 

Also, when I take off from a stop, I experience a hesitation and I have no power for a moment (even though I am pushing down on the gas).

 

Have you checked for vacuum leaks? Is the inside of the throttle body crudded up?
Have you checked the motor mounts? Since you said the idle was so low though I kind of doubt it would be the motor mounts.

 

Low idle usually indicates idle air control valve (IACV) is not opening to provide idle air. I would clean the throttle plate, throttle body bore, and IACV. Check IACV works w/ direct battery voltage.

good luck

 

Also, when I am attempting to accelerate quickly, the car will rarely go past 3000 rpms and that is with the pedal to the floor. It is as if fuel is not being delivered. I was driving the other day and I had it floored on the interstate and I was losing speed from 60 mph. Is this related to anything else I have mentioned above?

 

Fuel is probably the last thing I would suspect. Might check or clean the mass air flow sensor. I would also take a look at the items Texas suggested. I have had problems with the IACV in several cars but the symptom was that the car would not idle at all but would run when the gas pedal was depressed. Cleaning it has always solved the problem. Maybe ine were just REALLY dirty. It is electrical, so you should find the specs and test it with a volt/ohm meter before putting it back in just to make sure it works properly.

 

My first check on this would be the fuel filter. I'd besurprised if it were related to your low idle issue (which sounds more like IACV).

 

there is no fuel filter. if fuel pressure is low replace the pump. however, if there is low engine oil or a problem with the vtec circuit the pcm will not allow the car to rev higher than 2500-3000 rpm. it will seem like it hits a rev limiter. this usually sets a p1259, but if there is a problem with the gauge(bad illumination bulb for the check engine light) you won't know the code is there.

check if there are any stored codes.

 

Seriously? Never heard of a car designed without a fuel filter...

 

It's got a finescreen inside the tank. It's not a routine scheduled replacement. Only replace if you actually measure a fuel pressure problem.