Just bought a 1999 F250 Super Duty 7.3 liter. I don't have a map sensor. Or at least its not mounted where it's supposed to be. Why wouldn't I have a map sensor?

 

Do you mean MAF? Does a diesel have one? I don't know squat about diesels. But will probably be getting one.

 

He should have both. The MAP (Manifold Absolute Pressure) is used to figure the amount of boost from the turbocharger. The MAF (Mass Air Flow) determines the total amount of air moving into the engine.

 

I bought my truck used with an aftermarket intake. I found the sensor that should have been in the intake tube lying loose underneath it. Hope this helps!

 

The MAP sensor is usually mounted somewhere in the area of the rear passenger side and is connected to the intake manifold with a tube. I'm not precisely sure on a '99 cause I've not seen one. It measures pressure.

The MAF sensor is usually in the air inlet pipe between the air filter and the turbo. It measures air flow.

 

7.3's don't have a MAF sensor like the 6.0's.

 

Welcome to FTE.

Is the wiring to the MAP and the rubber hose still laying there? Was the hose plugged off, or left open? Kind of sounds like someone tried to fool the computer in regards to boost levels, but didn't know what they were doing. Any chips or tuners on the truck?

As long as the wiring is still there, installing a new MAP sensor will be easy enough.

 

So what's the sensor in my intake pipe (7.3)?? Looks more like a temperature probe rather than airflow. Anybody?

 

Where exactly are you talking about? There's the AIT (air intake temp) sensor on the filter box. There's nothing between the filter and turbo, but there is a AIH (air intake heater) mounted on the spyder or X shaped piece in front of the turbo that mounts to the intake plenums. It has a threaded rod sticking out the end and there are wires bolted on (ground and hot)

 

Thanks F350-6. It's gotta be the AIT. I failed to make it clear that I don't have the stock air filter box. It's a cone type filter (AEM Brand) attached by a stainless steel pipe to the turbo. There is a hole in the pipe for mounting the probe.
As for the air intake heater, I removed it and installed a plug. Here in FL I have no need for it, or the restriction it puts in the airflow.

 

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Moved to 1999 - 2003 7.3L Power Stroke Diesel forum.

 

Maybe this will help...... It is the green plug without an arrow pointing to it just to the right of the AIH Delete w/Boost Fitting.....



If it's not mounted look around for a loose wire or look at the picture and following the wiring harness on your truck and see if you can track it down.

 

Thanks I got digging around once I determined what the spider was and found it tucked in the back near the firewall. I think some one had shortened the hose because it wouldn't reach where it was supposed to mount without me rerouting the hose.