The check engine light on my 2002 Excursion (with V10 engine) recently came on and the vehicle starting running very rough, as if there were water in the gas. I checked the ODB II codes and it showed P0113 (air intake temp circuit) and P0102 (MAF circuit low output).

Since this vehicle uses a 6-wire MAF sensor, that tells me the intake temp sensor is built-in to the MAF. So I was going to troubleshoot the MAF (I hate probing the back of a sealed connector or piercing a wire), but I wanted to check the price of an MAF first. That's because I figured, based on the codes, I would be buying one anyway.

Upon looking at NAPA's website, I noticed that it lists an MAF relay in addition to the sensor itself. Since the relay is 1/10th the price of the sensor, and relays go bad as often as anything else, I was willing to spend (possibly waste) $16 to keep from having to pierce those wires. The proble is that I have no idea where that relay is, and a search of "MAF relay" & "V10" on this forum gives me zilch. The relay doesn't look like any of the relays in the fuse panel below the steering column.

Is NAPA full of it? Is there such a relay in this vehicle? Ironically enough, changing the vehicle to an F-250 instead of an Excursion makes the relay disappear from NAPA's parts list. I would have thought if the V10 Excursion has this relay, then a V10 F-250 would too.

Thanks for any insight you can provide.

 

There's no such thing as a "MAF Relay" on any Ford vehicle.

 

For probing connectors I've used one of my wife's sewing pins with good results. It will slip right in alongside the wire in a connector.

According to the 2002 wiring diagrams the MAF get it's power from the PCM Power Relay after going thru 20A fuse 2.22, hot in RUN/START after the PCM Relay is activated.

 

Thanks, projectSHO89. I thought something was fishy, since I couldn't find a single discussion about such a relay.

Here's a screen shot of the NAPA page. I guess I'll be piercing those wires, or at least trying to clean that sensor...

 

I knew I wasn't going to get out of this for $13.69. I guess I can send my wife down there, since she's used to buying things we don't need, just because it's cheap.

 

I'll try the needle trick. Thx.

I guess the PCM relay is what they're selling. I assume if that relay goes out, the vehicle won't run at all.

 

Correct.
The NAPA relay pictured is not the PCM relay used in 2002 - it is the other configuration.