1mz-fe hard cold start issue

[gduguid]

I have been having a hard time with a cold start, and can't seem to diagnose it. So far i have replaced the fuel pump, fuel filter, pressure switch, ect, cleaned the throttle body, cleaned the iac, and took the injectors off and cleaned them. It has gotten a little better, but still a little slow to start. Any ideas on what I can check next?

[Mister_Perkins]

did you check the resistances of the injectors? and also did you check the injectors for soaking? (loosing pressure while it sits) ? Hook a Fuel pressure regulator up and start the car up. Monitor the fuel pressure, then shut it off and watch the gauge for 20-30 minutes. See how much the pressure drops.

How did you clean the IAC and Throttle body? Just spraying sea-foam in the throttle body doesn't completely clean the IAC out. You need to physically remove the IAC and clean it to do it right. Did you clean the EGR valve? having the EGR stuck open will cause a no-start issue.

If you have Noid lights, I would confirm that the injectors are actually pulsing as well. Even if you clean the injectors that doesn't always rule out that they arent bad.

Do you have a check engine light on? Have you tried to scan for codes?

[gduguid]

no cel's. the iac was removed from the throttle body and cleaned. could this still be a problem and need replacing. the egr was also removed and cleaned when i removed the throttle body to clean it. after replacing the ect the starting got a little better, but still not a quick start like it used to be.

[gduguid]

throughout the day i have noticed that the cold start issue is getting progressively worse. the other day my friend who helped me with this said i should have a 3-5 second pulse which i didn't have. what controlts the pulse?