Rough idle

97 mazda 626 with 120k. 2.0 liter. Whenever I floor the gas either the car wont respond or it will start strong and then between 3 and 4 thousand rpm's it will start to stutter hard. Also, when I come to a complete stop and then try to keep going the car will either shut off or move very very slow. I recently adjusted the idle, cleaned the egr, and changed distributor cap and rotor, plugs, and fuel filter. Do I need to adjust the idle or is it something bigger?

What should I do since i've adjusted the idle screw? Should I spray the distributor and wires even though I just replaced the distributor cap and rotor?

Just had the timing belt change. Its in time now but it idles extremely rough at low rpm. Rides smooth when accelerating but jerks after reaching 4100 rpms down to 3100 rpms and does not have the same power it had before the change. I cant set the cruise control, speed drops if I remove my foot from the accelerator. We have changed the plugs, cap and rotor. Any ideas?

Could it be the egr valve?

My 1995 Mazda 626 idles roughly in neutral. The normal idle speed in neutral is supposed to be 700-750 rpms. The rpms are at about 700 but drop down frequently to about 550 and bounce up and down between 550 and 700. I noticed that there is a air duct hose that has a crack in it. Could this be the problem? Also, what does the air duct hose do? Thank you!

1995 Mazda 626 mileage: 102,000. I recently replaced the upper radiator hose, spark plugs and wires. When I started the car, it idled rough and would jerk upon acceleration. I rechecked the spark plugs for proper gap, checked the wires for connection and the firing order. All was correct. My muffler has a couple of small holes in it and someone said it might be the catalytic converter clogging up. I think I knocked off a vacuum line. What do you think? Thank You.

We do not think the muffler or the catalytic converter is your problem. You mentioned knocking off a vacuum line. If it is still off or incorrectly reinstalled that would definitely cause your problem.

Make & Model: Mazada 626 LX 1998; 4 cylinder 2 liter
Mileage: 96,000

Background info: I've had the timing belt replaced, I've replaced the IAC, vacuum hoses, new plugs & plug wires, cleaned EGR valve, had alternator tested - it tested good, replaced a/c & heater control unit. Local mechincal adjusted base idle.

The problem starts when anything puts a load on the motor - the a/c is the greatest drain. The RPM's dropped drastically when a/c is turned on. When alternator was tested I did notice a 19 amp drain on the charging system when the a/c was cut on. It went from 69 to 50 amps. Is this normal? I've pulled out the relay for the compressor and it still pulls down the motor with the a/c on. I've taken the compressor belt off and it still does it. I've jumped out the high and low pressure switches on the a/c system and it still does it. I've looked for a short in the wiring and can't find one. I don't have any check engine lights or codes. If my PCM is failing shouldn't I get a code? I have not had the a/c system checked yet. Any help would be GREATLY appreciated.

Yes. Correct the comp isn't engaging. I'm sure I have the right relay. I've even unplugged the comp clutch. And I've removed the a/c belt off the clutch, ran the car, turned on the a/c it still pulls down.

The a/c will not come on unless the blower fan switch is in position (1). There are five switch positions. (0-4) 0 positon is off and 4 is high. I have disconnected the blowers main plug, which completely takes the blower out of the system and when I turn the a/c on it still pulls the motor down. I think the blower is OK.

I Have the Haynes Repair Manual for my car. I been through the heating and air conditioning system wiring diagram and I did find one thing. If I pull out the 10 amp a/c fuse the problem goes away but, this also disables the controls for the a/c. The a/c fuse supplies power to the air intake actuator (part of the blower unit), swing louver (oscillating vents in middle of dash) and to the heater/ a/c control unit. (Which I have already replaced) I have also unplugged the louvers and the blower unit and the proble is still there. I wish I had a diagram of the control unit so I could see where the power from the a/c fuse go after the a/c switch is in the on position. Do you know of a place I can get this electrial diagram? Its not in the Haynes Manual.