Stalling when coming to stops

[nohandsnurse]

I have a 97 mazda b2300 that I used to drive before I got my current car. When I was still driving the b2300, I had an issue where the rpms would drop when I press the clutch in and break for a stop. They generally drop low enough to kill the engine. This only happens while the engine is cool, sort of. If i just let the engine warm up, it will continue to die when I let off the throttle but after driving it around for 15+ minutes the issue diminishes and then disappears. I had to drive the vehicle 30+ miles highway at the time and I found myself fighting this issue all the way to the highway and once I got on and off the highway, the diving idle would vanish. The car has since then set until I recently decided to get it working as a daily driver. Out of searching and reviewing old threads with similar issues I ended up replacing the IAC, cleaning the maf, changing fuel filter, changing fuel pump, and since I had an EGR low input code or whatever, I replaced the DPFE sensor. I vacuum tested the EGR Valve while the car was running and the idle did not change however I could hear the valve open and there looks to be minimal buildup in there. There has been no CEL since I replaced the DPFE sensor. Besides the issue disappearing after the engine is warmed for a bit, it almost seems like a Vac leak. I sprayed starter spray throughout the engine bay with no response from the running engine.

All of this was done but the issue is still there. Where do I go from here? Is there a possibility that autozone sold me a bad IAC? Any suggestions on what to do next? Thanks guys. I will probably be frequenting these forums more often since I plan to be driving this beast again.

p.s. I had to replace the fuel pump and filter to get the truck running, the fuel pump was dead.

 

[bcost882]

well the IAC can be cleaned i doubt it is but possibly a faulty unit but try fuel filter and run some injector cleaner. that might take care of the egr code. detergents do wonders

 

[suprapsu]

Take out the air intake and clean out the throttle body. It could be sticking. Also take some of that carb cleaner and spray it in your vac lines. It could be clogged up.

 

[Duane867]

Yeah, I wouldn't spray carb cleaner in the vac lines if I were you. They will dry them out something fierce...

 

[bsmithbyitch]

this may sound dumb and im sure you have made sure, but make sure the breather hose that connects from the air intake to the top of the motor is on properly, also may have a leak.

 

[nohandsnurse]

Well, didn't spray carb cleaner through the vacuum hoses. I did another sweep of the engine with starter spray with no change in the idle. All hoses seem to be intact and secured adequately. I have not changed the TPS sensor yet. The fuel filter and pump have been changed and the EGR CEL is gone. I am at a loss of explanations for this. I can't believe I am not getting a CEL. What would make my truck behave like this only for the first 10 - 15 minutes of driving?

 

[modelageek]

Well, didn't spray carb cleaner through the vacuum hoses. I did another sweep of the engine with starter spray with no change in the idle. All hoses seem to be intact and secured adequately. I have not changed the TPS sensor yet. The fuel filter and pump have been changed and the EGR CEL is gone. I am at a loss of explanations for this. I can't believe I am not getting a CEL. What would make my truck behave like this only for the first 10 - 15 minutes of driving?

ECT sensor?

 

[kimcrwbr1]

How old are the plugs and wires a coil give it a good tune up before you do anything