Exhaust Problem Help

[Pico]

As most of you know I purchased a new DC header and finally got around to installing it several weeks ago. Now here's the problem....the car ran fine with the pacesetter installed but now with the DC in when the car is warmed up it has a lack of power below 3000 rpm the best way I can describe it is as if it was running on 3 cylinders. I readjusted the valves, re-check and reset the timing, set the the cam gear at every setting possible, reset the ecu. installed new oxygen sensors,once I get above 3000 it's fine and full of power.
I'm stumped as to what the problem is, I've taken the header off too see if it was clogged and thats not it,
My cat was replaced last year but I cant see that being an issue, unless my running rich problem caused the cat to go bad with the pacesetter installed.
Any help would be appreciated, I'm getting tired of the car problems and almost to the point of saying bye bye to the accord.

[2oodoor]

oh no he didn't, take it back take it back :huh:
So the idle is nice and smooth?
Clean the air filter cone lately?
Did Cali switch to summer mix fuel already?
Have you tried advancing the timing (or retard) to a setting other than spec, use the light to keep up with how much you move it. YOu went obd didnt you? if not check your vac adv operation. Also test the map sensor.
Just a few things you didnt mention checking.... hope it helps. I am sure the header itself didn't change anything but for the better.

[Pico]

oh no he didn't, take it back take it back :huh:
So the idle is nice and smooth?
Clean the air filter cone lately?
Did Cali switch to summer mix fuel already?
Have you tried advancing the timing (or retard) to a setting other than spec, use the light to keep up with how much you move it. YOu went obd didnt you? if not check your vac adv operation. Also test the map sensor.
Just a few things you didnt mention checking.... hope it helps. I am sure the header itself didn't change anything but for the better.

idle is smooth, I did play with the timing and I have a new vac adv on the dist. that I bought from honda. I've also replaced the dist. with another one that I have laying around.
I know it has to be something simple that im missing, but not sure what it is

[2oodoor]

just a reminder for everybody, any time you move the cam gear setting you then have to readjust the ignition timing, every time >>... because the dizzy is driven by the cam, you move the cam, you just moved the dist too:)

Check : throttle cable to see if any slack got in it, it should move the instant you even breath on the pedal
O2 wires, could have got damaged and not getting the signal to ecm.
Vacuum hose to dizzy, do not use windshiled washer hose, it will suck together and close itself off.

[Oldblueaccord]

Unplug the fuel pressure regualtor and plug the line see if it runs differant richen up a little.
Not sure if the O2 sensors could be a problem maybe a bad one ?


wp

[2oodoor]

sounds like it is skipping on 1 of the 4 cyl ?


see below post V

[redaztec]

I had a similar problem with my Accord - almost no power at all under 2K RPM and still weak until about 3K. The problem ended up being clogged injectors. I doubt one or all of your injectors clogged exactly when you put the new header on, but I figured it's worth posting up just in case.

[Bass Man]

Damn. I wish that was Carbed... I could tell you exactly what the problem is with a carbed engine, but EFI is screwy to me...

If it sounds like it is missing, pull spark plug wire off at a time to figure out which one is not hitting the best.

[ghettogeddy]

I had a similar problem with my Accord - almost no power at all under 2K RPM and still weak until about 3K. The problem ended up being clogged injectors. I doubt one or all of your injectors clogged exactly when you put the new header on, but I figured it's worth posting up just in case.

all his injectors are new

[Bass Man]

all his injectors are new

Do you have to bleed injectors on gas engines??

[Demon1024]

Do you have to bleed injectors on gas engines??
I deeply considered putting that in my sig...
No you don't.

[Bass Man]

I deeply considered putting that in my sig...
No you don't.

I've spent a lot of time with Diesel engines, and they won't run right unless you bleed the injectors.

[Demon1024]

I didn't know that. don't know crap bout diesels. live/learn
just never heard of bleeding injectors before

[2oodoor]

all his injectors are new

irrelevent if you stop and think about it, take nothing for granted:thumbup:

[88Accord-DX]

If your car was running rich with the pacesetter installed, it can cause the catalytic converter to get clogged. If you can get a hold of a back-pressure tester that screws into the 02 sensor. Test it, you don't want any pressure more than roughly 2.5 to 3 p.s.i. of back-pressure.
I know you have new injectors, but a bad spray pattern can cause a mis-fire/stumble issue also. Oscilloscopes are good for looking at sensors, injector drivers & wave patterns in this sort of situation.