Hard cold start ( some diagnosis data)

[dochidalgo]

Yes, I've made some research work and I found excellent information about this issue in this excellent and reliable forum.
Now the first facts:
1) None DTCs with my scanner.
2) Two months ago the PCM was reprogrammed with a real time tunner man sat in the passenger seat....I have understood the pulse widths was changed among others parameters...Since then, the car pulls firmest and strongest than Fast Chip programm...But, I´ve noticed a little less fuel economy and water+carbon mix from the exhaust tips.
3) Fuel filter replaced about two months ago. However it could be partially clogged, but the car runs fine even at WOT...The racetronix injectors are one and a half year new.
4) No fuel odors from the fuel pressure regulator when I disconnected the vaccum line from it....
5) Cold engine Ignition On, engine Off: IAT sensor read 88°F/ECT sensor read 82°F.....That's my concern now....The temp difference between these two sensors must be 5°F maximum, isn't it?....then the ECT sensor is faulty? Even there is not DTCs P1114-1115?..
6) I'm in the process to get a fuel pressure gauge in order to get the readings from the fuel pump check valve....I hope the device is well yet ( 65k mi).

Thanks for read my post and mostly for your imput about this issue.
Dochidalgo

[Injuneer]

The small difference in coolant temp and IAT sensors is not significant. With a cold engine, and not running, the IAT sensor is going to respond more quickly to changes in ambient air temperature. The coolant is going to change temperatures very slowly if the only thing that is happening is the outside air warming up.

A difference between the IAT and coolant temp sensor is not used to set a code. The codes are set when the readings are unrealistically high or low, basically an open circuit or a short circuit. IAT codes are P0112 for short circuit, P0113 for open circuit. CLT codes are P0117 for short to ground, P0118 for open.

The important thing to look at on the CLT sensor is what it reads when you feel the engine is fully warmed up. It should be in the range of 160-210*F. If its reading too low, it will prevent the PCM fuel control system from entering closed loop. That could affect the engine fuel consumption.

[dochidalgo]

Fred..I really appreciate your accurate information as always.
My scanner show when the engine gets the close loop and based on your info and those data I checked today, seems to me that (by exclusion) my fuel pressure pump is gone. Now I am going to confirm that with a fuel pressure gauge...

Thanks a lot again
dochidalgo

[dochidalgo]

Fred...
Today the IAT/ECT sensors show 88°F (same mesure)???? at previous engine start. Ignition On, engine Off almost 10 seconds and the engine started just right.
The engine entered close loop at 110°F instead of 160-210°F...

I hope to get fuel pump pressure mesures later today.

Some imputs about these new data?
Thanks a lt in advance
dochidalgo