Check engine light then it quit!!

zstarch · 03-29-2008, 01:22 PM

91 Tracker 4wd wife's car, only 57,000 one owner miles. Used for short trips and almost never off road. Check engine light came on and off a couple of times, then yesterday while I was driving it (thank GOD) the check light came on and it suddenly just quit (no missing or stuttering, it just stopped and would not restart. Towed it home and about an hour later it started and ran fine with no light. Ran it up and down the street a few times till warm and light returned but vehicle still ran smoothly.
Now I am afraid for her to take it anywhere! Questions;

1. Will a stored code still read out if the trouble light has not come on again? I could take it to Autozone and have them check it assuming it will make it 5 miles.

2. This seems to be intermittant and light can come on whether hot or just started. What could be sensed that would make it stop the engine? I tried moving connectors hoping there was an intermittant connection but the light still went on.

3. I thought once the light came on it latched on and had to be reset using a switch or the service connector. But apparently with my problem this is not the case.
Any ideas or experience with a problem like this?? Thanks.

jtgh · 03-29-2008, 04:06 PM

hi ,
its an old dog like mine,and the codes are still there.
as long as you didnt unplug battery or pull DOME lite fuse (dome = ecu memory bank)
tune up this century? (hahahahaha) no seriously.

all it takes is a reg.size paper clip.
pull the codes.
there is a huge list that can cause die.

click CEL>>> Blinking-Lamp

click die: >>dies

any 8valve.
battery cables terms clean and greased.
Important grounds:

top bolt on starter main big black battery wire lug , nice and tight !!!
ground strap to body behind battery. clean and tight all these.
ground at base of DIZZY
ground at Thermostat housing. all critical to ECU.
any other ground straps at fire wall to engine. look and clean them.

other killers.
if it wont restart check spark.
spark OK.
then look for injection down air horn while cranking.
this car has the easiest injector in the world (in the throttle body) just look its in full view , unlike MPI cars.

spark , or fuel,.

or the TBlelt slipped but engine is free running and you are in no danger.

Yah, mines got 51k too,
it rolled over at 100k and now it reads 51k.
3k a year, suree........... HAHAHAHA

dont forget the Cel comes on at exactly 50k ( stupid useless service switch, throw hidden switch below column on kick panel)
or pull the whole switch out it is useless and annoyiing. red cel page.

zstarch · 03-30-2008, 11:59 AM

Thanks for the advice, I have a place to start now. Don't have a service book for it.
And yes it is 57,000 ORIGINAL MILES! I have the annual smog inspection reports to prove it! This is the bare bones Tracker, No AC, no radio, auto tranny, and soft top (that needs replacing next) I did just put new tires on it because the last ones were rotting! Not garaged, ever! I am thinking I should probably start replacing all those little vacume hoses that connect things together under the hood as they are probably about to start cracking and leaking. Replaced the fuel filter yesterday just in case but no change.

I don't think it has to pass a smog check in NC now because of age so wife gets a price break on the inspection. I'll check the codes. Think I will video tape the light while I do that in case I need a replay. Got to find some way to make this fun! Thanks.

jtgh · 03-30-2008, 04:30 PM

57k, sell it to me, please. wow what a find, 3k a year !

only driven on Sunday to Church.

hint, the MAP sensor hose , is the first to melt, ,correct mine was turning back to Dino juice (joke). but very true , melts as you squeeze it. (hot spot it is in)

your is low mileage so my nfo may be off base.
get:
EGR clean as a whistle.
new ECT sensor.
New OXY sensor
both will help give you high MPG.

is yours an 8 valve?

cheers.

zstarch · 03-31-2008, 11:29 AM

is yours an 8 valve?>>
How do I tell? The owners book says Type L4 in-head V type valves 97CID and 1.6 liter
Nothing about how many valves. Under hood looks like a rats nest of wiring and rubber tubes going to all kinds of little modules and sensors screwed into the manifold etc. What kind of idiot designs these things? If Pro Audio equipment was designed like this no one would buy it!
I think the EGR is the one fastened to the manifold with two bolts and I can see the diaphgram on the back side. What is the module above it that is held in a spring clip?

jtgh · 03-31-2008, 02:09 PM

hi:
look at engine top.
if it shouts in huge cast in metal letters 16 VAlves, then it is, if it is just black painted
steel valve cover then it is 8valves.

actually it is a very simple design, check out a 85 Toyota with VACUUM Controls for smog.

on an 8v the spark plugs go in to the head at an angle.
on a 16v the sparks go staight down , into the aluminum valve cover. Hemi like.
see next post

codes are stored, get em.

jtgh · 03-31-2008, 02:18 PM

which type do you have

Your vin number has a code that tells engine type too.
dont need last 5digit of vin cuz thats the SN. just prefix

zstarch · 03-31-2008, 02:33 PM

Opened hood. Engine very quiet No shouting. looks like an 8 valve

My idea of simple is my 1975 Massey Ferguson 135 tractor with the three cylinder Perkins diesel engine! No ignition, no warning lights, no computer. Just start with a key and shut off with the fuel shut-off valve.

I got a code 14 out of the puter. I cleaned the battery terminals and ground connections resetting the puter. Drove it about 3-4 miles till warm and got no light on and a code 12 when I came back. I can push on the diaphragm and get the engine to almost stall. Will try a longer drive when it stops raining and my son can follow me with the tow strap!

jtgh · 03-31-2008, 03:21 PM

yours is same as mine, 8v TBI.

your Engine Coolant temperature sensor is dead (or way off calibration)
or the wires to it are broken.
Mine was bad too. ( they age after 15 years)

this sensor , if it goes open circuit or reads high all the time will signal that the engine is
freezing all the time , I mean extreme cold.

unlike that Ferguson this car will start and run perfect at -40 degress.
how it does that is with the ECT sensor.

the fuel maps are temperture based ( unlike carbs and unlike mechancal injecton pumps)
this allows pefect mixtures at all times ( comparitvely speaking)

there are 3 sensors on or near the thermostat housing.
front one is engine gauge temp sender (not this)
then there are 2 more back from there.

moving back from stat, the next one is the ECT . a
and rear of that is the IAT (air temp sensor)

when you unscrew it , coolant will come out. (keep rad cap on so less water comes out)

if you want to test it, with a simple ohm meter, you can.
warm up engine (make sure it really is warm , 180-200deg F)
then measure the 2 pins , they will read 200-300 ohms.
if it is way higher , it is bad.

this sensor will cause a huge rich condition.
they cost $40 at rockauto.com , dealer may want $200

that is what I think is wrong.

EGR is not stuck open , good.

your ECT maybe intermittant, cracked inside.

BTW: if it does open, it signals up to 300% rich condition, really bad that will be.
that is how it works. Gas will not evaporate at -40d F , is the reason.

code 14 . , isnt it nice the computer saved you lots of troubleshooting.

zstarch · 04-01-2008, 12:29 AM

This makes sense. When it quit and would not start, it was probably flooded by the sensor! So an hour or so later it would start. I measured it cold and got an open circuit. I'll test it hot tomorrow if it stops raining and take along a 300 ohm resistor to jumper on the connector which would probably get me home if needed. When I order the sensor, do you think I should go ahead and get anything elas? Timing belt? Do they have Gates? Hoses look good, not cracked and not too soft. The engine computer was replaced about 4 years ago. Thanks for the help. I'll report back on this as I go along.