Terrible fuel mileage and new car to me

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Liveaction
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Posts: 10
Joined: Fri Jan 25, 2013 10:31 am
My tercel:: 1981

Re: Terrible fuel mileage and new car to me

Post by Liveaction »

Well thefuel mileage prior correctly installing the timing belt was 20 now it is 23 which is still not acceptable. I was not the one who did the timing belt so the shop that didit the first time redid it and said it was off a tooth. Well i didnot check itafter thesecond time assuming he set the timing where i had asked him. So i checked yesterday and it was at TDC so I put it 10 to the left of TDC which I believe to be 10 BTDC. And thats when i had the vacuum advance plugged etc and decided to check it and found it was not holding a vacuum. I have checked alot of other things mentioned above. I will just keep tryi.g for now but I bought the car as a little commuter car and will most likely sell it to find a car with better fuel economy. I am military and i am on the road alot so i dont have a lot of spare time to give this car right now. Hopefully i find something soon. Thanks again
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Petros
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Posts: 11930
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Terrible fuel mileage and new car to me

Post by Petros »

that car should deliver you 28-32 mpg, even better on the highway. Sounds like the shop you took it to is not familar with older cars like this (most of the mechanics likely have never even seen a carburetor). It should not be hard to fix, but you just have to be diligent to find the problem and to get it all correct. It will likely take more time to find the problem than it will to fix it. If the shop was so careless to mess up the timing belt, I would double check all of their other work as well, and not go back there again. to get the timing cover off you have to take off the fan belt pulley on the water pump (One of the bolts for the cover is under the pulley). Three 10mm bolts hold on the fan belt pulley, and five or six 10mm bolts hold on the timing cover. The mark on the front pulley has to be at "0", and the hole on the upper timing belt sproket has to line up with the mark on the head. It is an easy check.

Also, check for any vacuum leaks or misrouted or disconnected vacuum lines using the vac line diagram from this forum or the FSM. There is nothing to get intimidated by with this, despite the mass of vac lines if you follow each one from each end and compare it to the vac diagram it will only take about 15 min to do it all. If vacuum advance is not working than those vac lines should be capped off since it will act like a vac leak. It will not have any affect on drivablity to have the vacuum advance disconnected, but it will affect drivablity and economy if the diaphragm leaks.

You can set the timing yourself without a timing light to get best fuel economy: loosen the 12mm bolt at the base of the distributor and rotate the distributor a few degrees. Than get it and drive it, after warm up accelerate hard, up hill if possible. If you get no ping or re-ignision noises (crackling sound coming from deep inside the engine), than advance the distributor a bit more and try again. when you get noticeable ping, back the distributor off a few degrees and tighten the bolt. You will get the most economy when the spark timing is the most advanced without getting ping. to advance the spark rotate the distributor clockwise, to retard it turn it counter clockwise. Advancing it will also speed up the idle, and retarding it will slow the idle as a double check.

The factory emissions spec timing is only 5 deg BTDC, this is not enough for good efficiency and to protect the exhaust valves from overheating. 10 or 12 degs BTDC yields a cooler exhaust (so it perseveres the exhaust valves from overheat damage) and produces better fuel economy.

I know it can be frustrating when you are not sure what to do to fix it, but it can be fixed fairly easy once you put your might to it. Be patient and it will get done. good luck
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
Liveaction
Newbie
Posts: 10
Joined: Fri Jan 25, 2013 10:31 am
My tercel:: 1981

Re: Terrible fuel mileage and new car to me

Post by Liveaction »

http://spacecoast.craigslist.org/bar/3637355750.html
Well the car is running good but still gonna sell I may be high but I am pretty flexible on the price. If anyone on here would like to buy it I posted the link. I still am only getting about 25 mpg and i was just given a 91 honda accord that I will use as a daily driver. Thanks again for all of your help
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dlb
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Posts: 7305
Joined: Mon Jul 06, 2009 9:03 pm
My tercel:: '87 sr5, '83 dlx parts car
Location: bc, canada

Re: Terrible fuel mileage and new car to me

Post by dlb »

wow, that is in nice shape. throw some wide tires and a rear window louvre on and it would look badass!
Liveaction
Newbie
Posts: 10
Joined: Fri Jan 25, 2013 10:31 am
My tercel:: 1981

Re: Terrible fuel mileage and new car to me

Post by Liveaction »

so I am guessing I am crazy for paying 2600 for an old tercel cause I have not sold this car yet. What would a fair price be for this clean tercel thanks for any advice
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dlb
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Posts: 7305
Joined: Mon Jul 06, 2009 9:03 pm
My tercel:: '87 sr5, '83 dlx parts car
Location: bc, canada

Re: Terrible fuel mileage and new car to me

Post by dlb »

see my post in your other thread.
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Petros
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Posts: 11930
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Terrible fuel mileage and new car to me

Post by Petros »

Depends on your location, the fwd sedan is not as popular as the 4wd wagons. Most people are a fraid to buy a car that old, even if low miles and in perfect condition. Just a matter of luck if you can find someone who loved these cars when they were new, and would like to own one now. Unfortunately this version of the Tercel does not have much collector value because they were not particularly rare, though clean good running examples are relatively rare now.

good luck.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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