So I have decided to finally tackle my old van and get the ole girl running better. Last summer when I first got it, I took a trip to see how she'd do. Well 240 (to and back) miles later and roughly 150 dollars spent, I factored 5.5-7mpg. Blew my mind, lol. Anyhow, I just left her that way til now.

First things I plan to check is the cat for a plug, as well as o2 sensor/s. What else should be looked into that may be killing the mpg? Sure plugs, and wires are probably pretty old so may swap them out too.

How many cats and o2 sensors am I to expect on a 92 E150, with a 300 efi?

How do you go about removing either component?

Thanks for any info

 

first of all, you'll want to read the codes in the computer, it might have something to tell you about a failed component

o2 sensors can normally be removed by unscrewing them from the exhaust pipe with a 7/8 wrench or a socket built for the purpose. in cases of extreme rust, spray them down with a good penetrating oil, warm up the engine so the exhaust is good and hot, then try to remove them while its hot.

the cat is installed much like a muffler - cut the pipe around it and weld a new one in, or if possible disconnect by muffler clamps or other fittings. the cat will be the forward-most thing in your exhaust pipe.

 

ok thanks. Will definitely try pulling codes, no cel is on but its still worth a shot

 

1st things I'd look at are: air filter, fuel pressure regulator, vacuum hoses, PCV valve & dragging brakes.

 

An emissions test will give you an idea of how well the engine is running.
Check to see if your check engine light comes on BEFORE starting the engine. The ECM self-tests to make sure the indicator light circuit works, then turns the light off within a few seconds after start-up IF no codes are stored.

A few years ago, when I bought my van, I didn't notice this. It failed emissions the first time through simply because the bulb had been removed. I replaced the bulb, found a stored code for an EGR valve position sensor and passed emissions.

Autozone sells a code reader for about 30 bucks.

Actron/OBD I code scanner (CP9015) | Code Reader | AutoZone.com

Any sensor or control solenoid that is out of range or inoperative will store a fault code, may affect your engine's efficiency and your mileage may suffer, as well.

The 4.9 EFI system uses TPS, MAP, coolant temp, air intake temp, EGR position, O2 and knock sensors. It also uses an idle air solenoid, vapor canister solenoid and EGR control solenoid.

The fuel injectors fire alternately on odd and even cylinders; i.e. 1, 3 and 5 are fired simultaneously and then 2, 4 and 6 fire on the next revolution. Each bank is monitored for misfire detection but not individual cylinders.

The best I've done is about 16.5 MPG on the highway, empty, at 55-60 MPH. In town, usually around 14. If I load her up with 1000 pounds of tools or band gear and crank up the AC, it'll drop to below 12. She's never been a mileage monster but I'll race anybody to a quarter million miles.

Hope this helps.

 

thanks, havent had a chance to really look at her, but will when I get time. Looking forward to fixing her though, 5mpg is pretty ridiculous haha

 

If it gives you hope had a '93 cargo that did mid teens mpg, Low was 9, high was 18.

 

Does it smoke at all? Blow-by will affect your engine's efficiency as well. A compression check will give you a good indication of the internal condition. Somewhere around 140-150 psi with no major variations between cylinders, maybe 10-15 psi but should be fairly consistent otherwise. Access to #1 spark plug is loads of fun but the rest are in plain view. Do it. Do it now...

 

92 uses SD EFI and the MAP sensor is dominant in changing the A/F mixture, replace the MAP sensor.
Your van has 2 Cat's, a pre-cat (TWC) and an oxidizing cat (TWC w/A.I.R., there is only one O2 sensor and it's located upstream of the pre-cat.
TWC (three way converter)
A.I.R. (air injection reactor)
SD (speed density)
MAP (manifold absolute pressure)