Is there an intake air temp sensor on the older EEC IV MAP sensor type fuel injection as found on a 1994 E150 with 5.8 engine? If so, where is it located?

My Haynes manual for years '92 -'95 only covers the MAF type systems and doesn't mention the older MAP sensor systems. I have seen a sensor behind the distributor near the fourth or fifth intake runner. Is that it?

Thanks,
Gene

 

I don't think so.... There are two coolant temp sensors though.. One controls the gauge, and the other one controls the computer.

 

Thanks pfogle,

The van is running very rich after warm up and stumbles and sometimes quits running at idle. I started by catching up routine maintainance items including plugs, wires, cap, rotor, PCV, air filter and O2 sensor. I also rplaced the MAP sensor and the water temp sensor that has two wires and is right in front of the distributor. It was over due for the maintainance items and I shotguned the MAP and coolant temp sensor while I had it opened up. I also replaced my battery because it has been on the blink for a few months.

Didn't fix it.

I read up a little more and saw how many people were having trouble with the Idle Air Control valve, so I went ahead and replaced it and it's gasket.

Still not it.

If it has an intake air temp sensor it would be a good candidate to check, but with the problem I have with my manual, I am not sure if it has one or not. I have also read that the throtle posistion sensor could cause these symptoms, but it alows the engine to excelerate normaly and rev up and down as it should. When I have had trouble with a TPS on other cars, it was just the oposite. The car would idle but wouldn't excelerate.

There was never a check engine light except for a breif flash as the engine was dying yesterday during a test drive.

Any other thoughts?

I will probably see if I can get to that other sensor today that is near the fourth or fith intake runner and pull it out to see what type of sensor it is and maybe see if if the computor has set any codes.

 

Check the codes for sure... Even if the light's not on there can still be codes present. Certain codes can make the computer go into "fail safe" mode, which includes the full rich burn, which will ruin the o2 sensors as well. It almost sounds like a vacuum leak, or loose connection. The sensor in front of the dizzy is for the computer. I'm curious thogh, where did you obatain the parts? Wells (autozone) parts are not very good.. I have had to return some of that stuff more than once because it was bad right out of the box.

 

No Autozone parts for me! The only thing worse than having to fix something is having to fix it twice. I used all Motorcraft parts from Rock Auto except for the Idle Air Control which was an Echlin from NAPA. I checked the resistance on it before installing it and it was ok. It also matched the appearance of the original exactly except the new one didn't have the small spring surrounding the shaft inside of it.

I did look the engine over for vacum leaks while I was in there and found the hose from the PCV to the air cleaner off. I fixed that and replaced it's filter (forgot to mention earlier) on the first round of repairs. The fit of the PCV gromet is a little slopy and I will replace it but haven't yet. I also replaced the idler pulley and tensioner on the serpentine belt. Not important except to say that the reason I am doing the extra stuff is because I tow my travel trailer with this van and who wants to break down while you are traveling, so I'm fixing whatever else I find that needs it while I'm at it.

I probably lost any codes that were there originaly when I change dout the battery but I drove it about 12 to 15 miles yesterday after I finished working on it, so it may have stored some new ones by now.

Going back to the original problem for a minute, the tailpipe was extremely black and had a lot of moisture coming from it. The plugs were a black and the O2 sensor was black. There was a slight puffing noise in the exhaust in addition to the normal exhaust sound. There was no suck back on the tailpipe, no water in the oil, coolant level was normal. None of the plugs were wet. Gauge temp was normal for the coolant.

I was pretty sure the coolant temp sensor was the correct one. I believe the one for the gauge has a single pole plug on it and this one had two. The other sensor has a simalar plug on it to the coolant temp sensor that I changed and I have seen a picture of a Ford air temp sensor that looks pretty much like the water temp sensor except the tip is different. So I will go see if I can get to it and see what it is next.

Thanks again,
Gene

 

I found the air temp sensor. It was the one that I mentioned earlier. Looks just like the water temp sensor on the outside except that the plastic plug portion is white instead of grey. It has the same one inch brass hex as yhe water temp sensor too.
It was pretty gunked up with black deposits from the intake manifold so I cleaned it and the resistance changes as it should when heated or cooled. I should have tested it before I cleaned it but my hands were working faster than my brain.
Cleaning this sensor may fix it, but I'm getting tired of taking it apart and puting it back together. I'll see what else I can find while I'm in there.

Gene

 

On my 93 e350 with the 351w it started running bad , tailpipe black, black smoke constantly. So I did the complete tuneup , that did not help, well to make a long story short it was the tps sensor , changed that I had restored power and no more smoke!It took a couple of hours , pretty tight job though and a few skin knuckles! Well I hope this helps!

 

350wagon,

Thanks for the reply. I ran the codes yesterday and all it tells me is that it is running rich! Duh. I have borrowed a friends Snap-On scanner to see if I can get anything else from it today. I probably didn't help my case any when I changed the battery before reading the codes.

Were you able to change the TPS without removing the throttle body? It looks close to impossable with it on the bottom.

Thanks,
Gene

 

I found the problem. When I ran the KOER scan I found a code 173 which is engine rich, O2 sensor not switching. After scratching my head for a while, I did a search on "code 173" and turned up a good post that suggested checking the fuel pressure regulator for the pressence of gas on the vacum line. A light went off in my head just like in the cartoons and I ran down to the garrage to check it. Pulled off the vacum line, turned on the ignition key for a second and gas squirted out of the vacum post on the regulator. Pretty easy to understand why it would be running rich in that condition.

So I put a new reg on, pulled all the plugs back out and cleaned them up and put my new O2 sensor back in. I had pulled it out earlier to try and keep from ruining it.

Long story short, my van has never run as good as it does right now. Thanks to all.

Gene

 

Gene , glad you fixed the problem, and no you dont have to pull the whole throttle body, its been awhile but it seams to me all I had to do was take all the breathing equipment off and take 4 bolts off the front of the throttle body took off some small coolant lines that run to the throttle body, the front off the body came off then simply flip it upside down ,change the sensor , and reverse the process , all in all I would say it took a couple of hours.

 

Thanks again 350wagon.
That's good to know if I have to change the TPS in the future.
Gene