Mighty max sucking gas like crazy running rich???

hey guys i have a 1990 mighty max 2wd 2.4l 4cyl ive done a tune up and everthing on it replaced the o2 sensor and i added lucas fuel injector cleaner but my problem is the exhaust smells like the gas i pumping into it im getting an avg of like 14 to 15 mpg in this truck which is horrible for a 4cyl can anybody make any suggestions to fix it

ive got a 87 with a 2.6 i put a webber 34-34 on it with a msd box ive tried everything i can think of to get more mpg but mine gets 11 mpg. factory specs is 15-17 mpg, a buddy of mine has a 86 he put a f.i.s.h. carb on his says hes gettin 35mpg out of a 1 barrel carb hope this helps you

I don't think the OP has a carb, the 2.4 is fuel injected. It is possible for an injector to be stuck, fuel pressure reg bad, vaccum or air leak cause a lean signal to the o2 sensor, which can tell the ECU to dump fuel. There are alot of things, bad compression, loss of spark...

Are you getting spark? Fuel pressure check, and injector pulse. The first 3 things to check. It could be alot of stuff, its hard to pin point anything. Just check 1 thing at a time and eliminate as you go down. Good luck. I have the same motor in my 95, I get 24mpg in town. Good luck!

Pull the plugs. Then you can tell if it's a single cylinder, all the cylinders, or a combination. Go from there.

I too felt like my max was running rich (still think it is when I start it up in the morning) so I threw some of that Lucas stuff and some 93 octane gas into the tank and after a bit of a rough start - things seem to be much better. When I start it in the morning, the black carbon powder crap that is undoubtedly coating the exhaust pipe drops out with the condensation in the exhaust onto my driveway - initially, I went into cardiac arrest thinking it was oil in my exhaust - but its not... I think that will b a thing of the past soon. I am also thinking about yanking out the O2 sensor and cleaning that baby off before I throw $90 at autozone for a new one (YIKES)!

edit: just found a Bosch O2 sensor part # BS12053 on Amazon for $30 with free shipping!!! comes with 2 yr warranty. Pretty good deal, so I ordered one.

I picked up a sensor for my '87 at Advance Auto for $19 w/a 1 year warranty. Half of what AZ wanted.
They're easy to check w/a digital volt meter. Disconnect the sensor, start the vehicle, sensor should read about .5 vdc at idle. Rev to 2500 rpms, sensor should jump to 1vdc. No reading or no jump, sensor is bad.
OP: I'd do a compression test when you have your plugs out.

OK, so I got my Bosch O2 Sensor from Amazon today... and it only hase one wire and a different connection. Is there any way to "wire" it so it will work? Or do I have to go through the return ordeal? UGH!!! FWIW, like I am sure many of you guys my 92 has a blue wire and a white wire, but the Bosch replacement only has one black wire. This is frustrating, because I saw in many places on the web that this one was money and it will work. Any and all suggestions are welcomed and appreciated, thanks in advance.

SOunds like you got a universal single old school wire o2 sensor. Wont work. Just get the right part, and not online. LOL.

Do you measure the voltage with the sensor hooked up, or unhooked? Will it be the same on the older style single wire? I have an 89 2.0 liter and so far, I'm only getting 12 mpg.