Starts, runs 30 seconds, then dies

[fixkick]

Hello, I have a 1994 Tracker 2wd 8 valve. I bought it a few months back, after driving it home, it would not start back up. Been working on it since with no luck. At this time, after sitting for a day or 2, it starts right up and runs for about 30 seconds then dies. Crank again and nothing (until at least a day later). When it first starts it runs smooth then stumbles and dies like running out of gas. Looking down the throttle body, fuel looks the same though (as it dies). No SES light (or codes). Have already swapped out the distributor, plugs, wires, ignition module, fuel regulator, fuel filter, MAP sensor. Removed and cleaned the throttle body. Checked the fuel pressure and it is good (can hear pump run when turning key on). Gone through the vacuum lines and most of the grounds I could find. Exhaust was terrible when I got it with a huge leak at the manifold/pipe donut. fixed leaks and deleted the cat convert (exhaust complete going out the back though). Good test that no melted CAT test , bravo that)

Thanks for the great website / forum, wealth of information to say the least!!

94TrackerDriver,. no transmission stated sadly/

why replace all that spark stuff if a simple spark passes on all cylinders? \
but this fact here tells you it has fuel, Looking down the throttle body, fuel looks the same though (as it dies).
so is  only 2 things, dead spark or the cam belt slipped.
All G16 any time they mess up, for any reason, and for sure day 1 new, to your gargage,
the front crank pulley bolt, 17mm head bolt must be set RHT , to 94ft./lbs,  not 30 not 60 not 10, not 5, but 94 ft/lbs or the key will SHEAR and strip.  and then cranking it 50/50 chance it might start as the poor things jump around like crazy or not..
when the engine fails we check spark, no more easy car in the world is so easy to do on this 8valve engine with spark plugs in FULL VIEW>
if that fails the spark is gone. (we work spark then) if spark is good with test spark plug new connected. to spark wire,
the next steps is compression test, a $20 tool at harbor fright.(pun)

The CAM belt is only good for 60k,miles,  tad longer but why walk home, do the service, as stated in the manual..
the compression is 160 not 100 no 50,  psi.  takes 5 min work on #1 front,  then do all 4,  if one looks ok..  2 and 3 or 4 can fail, and make things real bad, for sure vacuum bouncing. from burned valves. Intake.

1: injector injects as it dies,  so not fuel, even using spray test fuel proves this in minutes.
2: spark test, good or bad. then try all 4. using  test spark plug, gapped at .028" never use .045  as the machine that made them does (NGK does .045" new in the box>
3: spark passes ,  compression is next, after checking 17mm crank pulley bolt first. 

just 3 tests and total  cost $20 not $100 for parts. ever. (cap/rotor/wire set is given and is a tune up with new NGK plugs. etc.)

if test fuel passes(runs for sec)_, sprayed, we can then do pump tests would be next.

one other test is with diagnostic jumper in place
crank dead engine for full 5 seconds, CEL flash code 41 or 42 is BINGO.
does CEL flash 12 now? for sure dead and for sure 5 full seconds?

lit me explain the CEL, the check engine light codes, the ECU needs the crank to spin  a minimum number of turns to tell you some things are bad cracked, thus my 5 second rule.


facts on spark this 91 to 95 ECU on all kicks
the ECU makes all spark and all advance
like this,
CMP >>>>ECU>>>>ignitor >>>>coil , >cap >rotor wire set and 4 spark plugs.

any thing in this path will cause dread spark. or be intermittant..
The ECU does report CMP dead. and primary of COIL dead, for sure. I can demo that fact.

the ECU never knows spark made it to the spark plugs. nor if timed right.. (only you can get timing right..)
if found way off spark timing at dead engine, the cam belt or cog slipped. a Timing light sees that and DISTRB base bolt is not loss we know for  fact the cam is now slipped. (only why remains) one more $20 tool at harbor fright.(sic)


No SES light (or codes) what does that mean the lamp is dead, or?
the CEL/SES must glow at key on, if not lamp is bad or the ECU IS DEAD,  that is what the lamp means key on, ECU booted and is NOT DEAD>> now.
then with DIAG jumper in place code must 12 happen, at any time , keyon only, idling or even driving at 50MPH or any speed .  Keyon only is stored codes too.

All codes but 12 are bad, 51 is bad EGR,  higher numbers never good.
lower are catastrophic errors, 13 up.. means hard error, and must be addressed.

that is  it on no starts.   I think, good luck to you and the car both.  cheers,