8mpg and backfiring. Please help!

[RWB0481]

I have an '84 FJ60 (218,800 miles)with the stock engine and toyota carb. I did a tune up on it when I bought it about 3 years ago and it had been running fine and averaging about 13mpg (pretty normal from what I hear/read). But lately (past 6months or so) it's been getting only about 8mpg, smoke coming from the muffler, and when I turn it off the engine dies then sputters back to life for a second or two and then backfires(usually but not always) and then cuts off. It's had the fuel pump and filter replaced in the last 2 years. As far as I know the carb hasn't been rebuilt. I notice the smoke coming from the muffler mostly when I start it and almost always on acceleration. I hope this makes sense I know I jumped around a bit, but I want to tell as much as I can.. Hope you guys can help. Thanks in advance.
Wesley

 

[Fuzzy Logic]

Time for that 2nd. in a lifetime tune-up

 

[Waggoner5]

Yep, plus carb rebuild and timing check.

 

[RWB0481]

Thanks! I was hoping it would be something so simple. I'll work on that this week and be as giddy as a school girl when I can once again go more than 150 miles on a $50.00 tank of gas!

 

[RWB0481]

While I'm in there is there anything else I should look at replacing just for routine maintenance?

 

[Devils Paw 80]

If it ain't broke, no need to fix it. Save your coin for a future engine rebuild.

 

[brian]

sounds like the fuel shut off solenoid, isn't shutting off when the key is turned off.

 

[Martin White]

If you want a project, how about putting in a Cummins 4BT? I love reading the writeups of people that do those kinds of conversions. Intel suggests you will get something in the range of 25 mpg. Food for thought.

 

[nikos8]

Check the timing and fuel cut off solenoid.

 

[Mountain Goat]

Ditto on the timing. The engine can also diesel on shut-off if you have the idle set too high. Many folks try to bump up the idle speed as a first pass attempt to fix a poorly running engine.

 

[RWB0481]

Martin, I've been thinking of doing that in my '74 FJ40. My dad is a Mercedes diesel/ veggie oil fan and has been trying to talk me into "buying a bread truck" for the 4BT. He's the gearhead and I do all the body work. Off the subject but you guys will probably get a kick out of this. I had a new patient the other day that was a wiry and gruff looking old man and dreaded seeing him. But we got to talking and he owned a VW dealership in town for about 20 years. He was telling me he had this "tent thing and a luggage rack" that he was looking to get rid of to make room in his garage so I said I'd gladly take them off his hands. Not expecting much I went to his house to pick them up today to find that he was GIVING me a roof top tent and 6ft. roof rack that were VW dealer accessories in the 50's and 60's for VW buses!!! Both are in great condition and look awesome on the Land Cruisers! The tent was made by a company called Air-Camping and is about 6'10" long by 4' wide and folds to 4x3.5... What a day!!!