DAM CAR!!!

[blade]

Hello everyone i need to ask so questins about the car and it's fuel mileage. my car 1987 tercel 4wd auto 1.5 3ac has a problem. i have been driving it to high school every day now for the last 4 days and i ran it to find the gas milage and it is Dam sad to be truth full a waping 16 mpg's what is wrong with it. I love this car but i can not afor to drive it like that. it has a bit of a desileing problem but i have been trying to fix it but can seem to get it out. i have cheaked for vcum leaks and there are none.WHAT DO I DOOOO?? this car is not quoperating with me i try to fix it,i buy all new parts no used but it seems to be getting worse as i touch it so i am oing to parkit till i can get this road pig workin like it was 23 years ago. all of the help i can get would be much appresheated.


Thanks
Calvin (blade)

[Jarf]

Blade - more info please. What is the mileage on the car? how does it run? does the exhaust "fart" or is the exhaust stream smooth? Just exactly what have you replaced trying to "fix" it?

Does it pull when driving or when braking, have you checked the basics (tire pressure....)
Blaming bad mileage on the engine may be a good call, then again, it may be totally off base.

When you say dieseling, what I hear you saying is that when you shut the car off it wants to keep running. Most common cause is too high of an idle, but there are as many causes are there are blades of grass, so again, more info needed.
Bottom line is you have to go back to basics and evaluate just what you have. Check both cam and distributor timing, make sure the T-belt is in good shape. Plugs, cap and wires all have to be good too.
Also of note, be sure you are actually calculating your mileage correctly, it is far too easy to do it wrong. (fill tank to a repeatable fullness, record mileage, drive, at next filling, fill tank to same level as before and record the mileage. The distance you have driven divided by the fuel from the last fill-up, is how you get accurate numbers, anything else is just a guess). Weather and traffic and average speed will all have an effect on the final number.
Lastly, check your tire size, if they have been "upgraded" to a different size it could throw off the speedo/odo and give false mileage readings.

[blade]

ok so the car it's self has 265,336 KM'S but the motor only has 94,056km's on the dot. it runs good. now i have had to do some temp stuff to the exhaust. there is no muffler. it roted out and fell so i just put a peace of pipe on to account for the muffler. i have to fet a new exhaust from the cat bak to the muffler. and when i let go of the gas the ehaust dose pop. i have put in new plugs all new vac hoses on. it dose not pull in any direction and i have put brand new 175/70 R13 tires on.so how do i set the idle?? oh and i thnk i need a new throdle spring because when i have the hood up and the car running if i grab the throttle and push it down the car will idle at a lower rmp but if i let it go it idles high again. ok so how do i check the cap??? what is a cap?? the timing belt is brand new . how do i cheak the cam and distributor timing?? i was told by my dad about the speedo and odo so we did a test and i am out 3 km's i hope this could help you help me.
thank you for getting back so soon.

[Jarf]

While the exhaust isn't helping things, it wont cause a high-idle.

I would be willing to bet that your carb linkages are seizing up, possibly the choke or fast idle linkages are not free.
Resist the urge to install a big spring, better to find out what is making it hang up rather than forcing it to return home, (that method often results in further damage, think bent throttle shafts).

Did changing the plugs and vac lines make any difference?
Has it always run this way since you have owned it, or is this a new to you problem?

As to the exhaust, stay away from multi-piece replacements, they are a pain to install, often leak at all those joints and rust out much faster. Bosal has a decent 1-piece available and of course Toyota still has the OEM pipe available.
The Toyo part is the way to go, last time I did it, it was cheaper than all other alternatives, fits the best and has a pleasing exhaust note.
Worth making the call.

[dlb]

blade, i have a weber carb so setting the idle on mine is different but i believe on the stock carbs you simply adjust the two nuts on the cable that attaches to the carb (possibly called a throttle arm but i really have no idea) so that, when the cable is at rest, it does doesn't pull on the arm quite as much as before. i think the 3A engines are meant to idle at 800 rpm but if you don't have an SR5 you probably don't have a tachometer, so maybe try setting it as low as it will go while still running smoothly. you'll have to play with it to see if it still diesels. i don't know about the throttle spring being shot, take jarf's warning to heart before trying a bigger spring.

the cap jarf referred to is the distributor cap, and it's part of the entire distributor or "dizzy" as it's sometimes called. click on the FSM (factory service manual) link at the top of any of the forum pages and click on the ignition system page on the left, then click on ignition assembly and it has a diagram of the dizzy there. it's really easy to find IRL because all the wires from the spark plugs go to it. to check the cap and rotor you just pop the two metal arms off the cap and it will come off of the assembly. inside of it are 4 metal contact plates and they should be pretty clean--if there's too much corrosion, the "spark" won't get through very well. the rotor will be right underneath where the cap was, it has one metal contact plate on it that you should check for crap as well. if they look bad, replace them.

i don't know about checking cam timing, but for distributor timing you usually want to use a timing gun which hooks up to the battery and a spark plug lead. i've never actually used one though because i've found it easy enough to just do it by feel. you just loosen off the bolt that holds the dizzy in place and slowly rotate it one way or the other. does your engine make a clicking or pinging noise going up hills? that would indicate that your timing is too far advanced. dieseling is another sign of being too far advanced. if your timing is retarded (that's the actual term), the engine will perform sluggishly and run quite hot--too much of either one advanced or retarded is bad! generally, you'll want to turn the dizzy so the revs come up and the engine sounds happy, then take it for a cruise and see how it performs and if you hear pinging at all. if you do, turn the dizzy back just a little bit and test drive it again. ideally, you want it to be advanced a little bit but not pinging.

if i gave any bunk advice there, someone please correct me.

[xirdneh]

i've been messing around with these cars for decades and the biggest pain in the ass is the carbs
they account for 95% of the engine problems
when i have those problems i switch the carb with one that i know is good to rule it out
then i look at other things

[Jarf]

I didn't go into all the timing things to check as you mentioned it runs well, if the cam timing was off, it would be a DOG below about 3000rpm or it would just be a DOG period. Given what you have said I doubt your issues lie there. For the record, cam timing requires you to pull the front cover for the timing belt, set the crank to TDC #1 (firing) and verify that the little hole in the cam sprocket matches up with the pointer on the first cam bearing retainer cap, but I doubt that is your issue.

As to adjusting idle speed, if you follow the cable to the carb it is attached to a bell crank, which in turn is located on the throttle shaft, there you will also find a little screw that acts on the same bell crank. This is the Idle Speed adjusting screw.
Those nuts that hold the cable in place should never need to be touched, they set the cable length and like handbrake cables, should never need adjusting. Only if someone was in there and messed about would you need to go there. If you are wondering if that is your issue, once the engine is warm and the choke circuit is off line (no more fast idle) then look at the Idle speed adjusting screw to make sure the stop is at or near the screw. When it is all correct there should be a little bit of slop in the cable where it comes off the bell crank, if it is under tension then indeed someone has been there and you will need to correct the mal-adjustment, if there is a bit of slop in the cable, verify that that the bell crank is indeed contacting the Idle Speed screw. If the cable length is set correctly, you should be able to undo the IS screw until the engine stalls without the cable hanging it up.

Setting the timing by ear is okay for an interim thing but it should always be verified with a timing light, the human ear is not capable of detecting pinging unless it is really intense, all I mean is that if you can HEAR it pinging you know it has already doing damage.

The Carbs on these cars can be a real PITA but it is not the end of the world, work your way through the FSM and you will be able to sort out a lot of stuff. It can be daunting as there are 2 solenoids, various devices and many linkages, really though it is relatively straight forward stuff, just take it one system at a time and you will do fine. I doubt you actually have serious problems going on, more likely lots of stupid little things that are having a cumulative effect, especially if you recently bought it, many cars get sold because the owner just can't get if fixed right.
When I bought mine, the dist timing was off to compensate for the cam timing being off, the timing belt was loose and the valves were adjusted backwards (12 thou for the intake, 8 for the exh) didn't run well at all but I knew it wasn't terminal and I still paid big bucks for it as the body was clean, but I digress....

[blade]

well dam i need one of you guys up here. you all seem to know what you are doingand you make me sound retarded. lol well Jarf were did you get the exhaust and what was the $$$ if you don't mind me asking??.and i will start going throw the FSM and see what i can do.

[Trev]

Wow, my car has a recent "dieseling" problem too. I just bought a diesel truck too, and I am glad to say i get better mileage in my diesel than you get in your car. lol.

Does it run rough? Must be running REALLY rich. Pull the plugs and see if they are black.

[takza]

Try taking the top off the air cleaner...wingnut and four clamps....and check to see if your choke is open when the car is warmed up. The choke blade should be vertical. If it isn't...use some carb cleaner on the shaft till it loosens up (need to hold the throttle open some to be able to move it full range?)...then some light oil. If you are going thru that much gas...it will be sure to diesel when shut off due to all the carbon.

[Jarf]

Blade - My car is 5spd, so don't use my numbers, Auto trans cars use different fr and rear pipes though I believe the cat is the same.

From Weitzes Toyota on April 09, I got 17410-15130 (fr pipe) list $102.10, 17430-15181 (muff/tail) L=$250.30. The 3 gaskets were all about $3/ea.
Make sure you check the prices when you order as well, the rear was $150 when I priced it 6 mos prior, I was not impressed when I picked it up, after the install, I did not mind at all.

Well worth getting comparison pricing out of the US and use it as a lever, however I would not order exh from the US, for some reason exh pipes always get bent in shipping, if your local dealer arranges the transaction, he will be responsible for the shipping, if you order from somewhere else, it will be your pill to swallow and chase the shipper for compensation.
Also helps to make friends with your local dealership counter person, sometimes I even take in a round of coffee's when I go.

Personally, I would sort out the high idle/run-on issues before dealing with the exhaust.
When the time comes to deal with the exhaust you will want to take a close look at the convertor, running that rich may cause some contamination in the convertor, they are fairly robust but if you inspect it while your in there, it will be one more piece of info you wont have to guess at.
( with the cat off, you should be able to see diffused light through the cat and no chunky deposits on the input side of the honeycomb, no visible cracks or loose bits inside. Also a good idea to put a mark on one end of the cat as they are usually directional and you don't want to install it backwards as that could create more problems)

Takza's suggestion of looking at the plugs is a good one, as it will tell you a lot about what is going on inside the engine, reading a plug can be hard (in the beginning) but posting a pic will get a lot of input. If you have access to a compression gauge, that too will tell a lot, if you know how to interpret the results.

My wife tells me I don't always explain things well to other people, as I make too many assumptions about their level of understanding.
So if you need more (or less detail), let me know and remember the only dumb question is the one that isn't asked.

I would be more than happy to come out and help, you buy the plane tickets and I will be there.

[Petros]

You need to verify your ignition timing. With the ping and dieseling it could be the timing. THat alone could affect your economy significantly, and do damage to your exhaust valves and head gasket. There is no easy way to do this accurately without a light, see if you can rent or borrow one if you do not have access to a timing light.

[blade]

ok so the timing is fine nothing wrong there so next step??? and i have recently noticed that my car is doing a sloght pull to the right and when i go over bumps he right of the car is makeing a clunking sound only in the front the car just had a wheel alinment so that is good. i have been told it could be a cv or a ball joint ???? what can i doo to find out.

[garyfish]

A leaking AAP diphragm could be part of your fuel-economy problem. (AAP = Auxiliary Acceleration Pump)
Read all about it here:
viewtopic.php?f=4&t=5415&p=39556&hilit= ... ion#p39556
viewtopic.php?f=4&t=5433

Also, there could be a leaky diaphragm in your mechanical fuel pump??
viewtopic.php?f=4&t=5559&hilit=diaphragm#p40639

Check out these other threads for more info on T4WD fuel economy:
viewtopic.php?f=2&t=5014
viewtopic.php?f=2&t=3284