Hi, I am in need of help with my truck. I just did the head gasket and had the head surfaced, put in arp head studs. Put the truck all back together and now it starts hard. It takes two good cranking sessions when it's cold(40 degrees) after sitting all night and even with the engine hot it still takes a good 15 second crank to fire. The truck was extremely hard to start after reassembly, it took a lot longer than normal to bleed the fuel lines than previous times. My grid heater is working and my wait to start light is working. So why is it starting hard? It used to never crank more than 2-5 seconds cold. I can't find the plugin for the IAT sensor after putting the head back in, could this be causing the hard starts? I'm sure that's what tripped the code. Sorry if this seems dumb, but I need help. I did all the work myself in my garage and don't want to spend any more money. I'm already about 1000 into this repair. Any help would be greatly appreciated, thank you

Definitely need to plug the IAT back in. I would have to suspect it would have the tendency to run like chit without it. I don't think the lead is very long it has to be back there somewhere.JR

I think I solved the hard starting. I went and retightened the overflow bolt at the back of the head. It starts right up now. I'll verify it in the morning when I start it to go to work. Thanks for the help, do you know if the IAT plugin comes out the same place as the MAP sensor plugin?

I went and looked at my soon to be installed wiring harness. The map and iat both branch out of the harness at the same place. They are only about 6" to 8". It has got to be right there unless you cut it off. You also should replace the sealing washers on the return line. They are probably shot. Might have been the reason for your original hard starting.

That would explain why I can't find it, the person that owned it before me must have cut it off. Even the map sensor had been spliced. How many wires go to the IAT sensor? Where did you find the new harness? And how much did it cost? If its not bad maybe I will just replace the harness next

That would explain why I can't find it, the person that owned it before me must have cut it off. Even the map sensor had been spliced. How many wires go to the IAT sensor? Where did you find the new harness? And how much did it cost? If its not bad maybe I will just replace the harness next

2 wires to the iat. I bought my harness off of someone parting out a truck over on CF for $75. A new one is around $800 IIRC.

Are they yellow in color? Sorry for all the questions but I think I found the wires that go to the plugin. If I can find a plug for the sensor I will just splice them and put it in. Thank you for all the help. Any thoughts why it would have thrown the code now and not in the last 10k miles I have had the truck?

Mine are black with a blue tracer and black with a brown tracer. it has the same connector on it as the ECT connector. i just replaced that one a while back and bought the connector with leads from Rock Auto. No idea on delay of the code though.