95 tracker miss after warm up

[fixkick]

tps was calibrated...
have checked all wires from tps to their other ends
no bad wires.
found white wire from cps has shielding that wasn't connected to a ground on cps end...just laying in looming...grounded
tested wires from cps to coil, ignitor. noise suppressor. and cpu.... all wires checked good
not sure how to check suppressor.
every thing runs good till warm up then the problems start
havent driven it since all this
mounted cpu on kick panel to ease in testing wires to cpu... it is grounded btw.
started and ran fine no codes but didnt have time to drive it or warm it up.


the timing retarding was happening before the tps code showing up
with the code it still drives the same except the same timing jumping to 3* atcd


wish i had a spare cpu to test
would the noise suppressor cause intermittent timing drop

the timing jump is very intermittent and is happening on at lest the front two cylinders witch was all i tested with the timing light.

the jump is purely caused by ECU.  ECU runs all timing advances.
as I said Failsafe (limhome) mode can last 1 second and clear, so fast you can never see it happen. CPS sensor is one that can do that. (hit clear, ok, ok , hit) hit/clear is DTC.
CPU failure cuts dead all spark totally at the coil (spark coil)
why not try a new spark coil if you thinks spark is bad.

the ECU been RECAP'ed yet? ( I forgot this)
the retarded spark jump is ECU created or one input to the ECU is wrong. or a  bad ECU.

to find that kind of error on any car for sure this old, takes a scope,to find what input is bad to the ECU. at the odd event. (hot engine)
lacking such tools and long hard work one can only guess.

I do not believe the noise suppressor is bad and they are very rare to find, super rare and is only a cap and resistor inside and very super reliable.

but suppressor output on the brown wire is the TACHOmeter output, and if it fails for any reason (drops out) the ECU instantly cuts all injection.!!! even for 1 second happened.

a shorted out tachometer or cruise box will do the same thing  , cut all fuel injection dead, for the duration of the signal lost at the brown wire.

why it does not fail on cold engine?, is a key fact too.  a part (any) warms up and  fails, is the cause. of that, a thermal failure.

A bad spark coil, bad Distributor, bad ECU,  or any other sensor is intermittent hot. (iat,ect,cps,02,tps) cps=distrib fail, cam pos. sensor )


not sure me.

[fixkick]

1995, 16v, misfires only hot (normal engine temp, 180F) faulting  TPS cured,  tune up done.

the only other bad readings for evidence, is post #1
"150 ish all cylinders" ( bad tool used or done worn or at high altitude) or bad engine with all 4 equally bad the same,(no way 4 same worn I say)
195 PSI  is normal to get 150 on this engine one needs to go up a mountain, to a tad over 8000 feet.  you are not that high, so test done wrong.
VAC tests:
vacuum tests at idle, 800 rpm hot,?
Funny evidence,, not sure.
funny injectors sounds.  (not sure how you know that, a stethoscope)? if this is truly real ?, that means key evidence  of the ECU is bad , seems to me. just that alone. (more later on this)


The compression test  is top grade very important test,  never seen ever below 183 me, 16v, has higher compression than the 8v, so runs 25more PSI on 16v.
the fact is all 4 are equal, hinting to me test done wrong if equal. most engines made the #4 rings go  bad the hottest cylinder would fall first. and did not.
the test must be with a good gauge. (best is to own 2 so you always know 1 is not bad or  was dropped and damaged and lies)
The test is done , battery not weak, spark plugs pulled to attain maximum RPM, and done at least warm engine not dead cold engine ever. warm or hot yes.
the test is done with the throttle blocked open (some) so the engine has AN air supply, or and let the needle on the gauge peak out and release key./
do not count crank turns, as some do this is wrong, this act.
the other big test is vacuum, most do 19inchdes  Hg,at hot idle,  800 rpm, no bouncing vacuum allowed.

that is review,  I am not saying engine is bad, I am only pointing out one key test failed here, compression. failed hard in my book.

my lawn mower does 100PSI, and my boat motor 125(old)  this car has way way more compression ratio , way more.
This how how it gets 95HP, (one huge factor and 1.6L) CR )compression ratio)9.5:1  (8v= 8.9:1)

I think the ECU is bad, if the injectors make some crazy sound
but watch out , for some cars injectors,  some ECU made have 2 modes. one is ganged mode an the sequential injection x4.

on more comment on funny sounding injectors:
some ECU run ganged Injection mode under only some rare or only cold engine.  not saying this CAR, does this mode change as some do.

Is this ECU RE-CAP"ED?  most Ive seen If never touched after new car sold are in fact bad.  they dry out and are bad, that is what electrolytic caps to
it is there failing. (some brands can go 50 years, I have seen , in my kenwood  AMP here with nice NEC caps still good from 1969)
New caps best are Nichicon™ top maker,  Japan made, (design,   not plant locations) sold at mouser.com , easy to find and get. Low ESR, and 105 deg. C rated.

[fixkick]

it can be lots of things, even bad wiring
old cars mostly have like 5 things wrong, not just 1.
the most hard problem of all is ECU bad, as proving this true all inputs to ECU must be checked for good.
All ECU fails with bad inputs as all computers do.
sensors. acting up. (all)
or ECU finds it self out of control on fuel mix. or spark not correct that it controls.

ECU;s can get lost (out of control). there are 3 main loops on a hot engine in the CPU,
Idle control loop
spark advance control loop (CMP is the initiator only)
injection rates and 02 based. and WOT rules. (accel modes) loop. controls fuel mix at all times.
the loops are sub processes in the ECU.

there is limphome mode too, that undermines all the above, a place not to be ,even for 1 second, for sure not repeating.

[1995 toad]

compression was done stone cold...
engine runs great until timing changes intermittently
i thought it was a fuel injection problem at first
so checked all the fuel sensors and all checked good
then did the caps still intermittent miss
then i decided to check timing and found the timing jump...aka miss
 so then i started checking ignition components
and the timing belt was taken apart to check keyway


before i did any thing i did cap rotor...making sure they were brass...wires, plugs and fuel filter 

then the tps code showed...
so i thought i finally thought i found the issue...nope..
so now i have traced wires made sure they were all good

all the while it has been drivable very annoying but back and forth to work until november. under acceleration it was fine and idle it was fine...havent driven since i did the tracing and bonding of the coil wire shielding..

[fixkick]

was done stone cold... (is useless test but I bet normal warm hot)  It is bench mark test and leak down test even better
engine runs great until timing changes intermittently
i thought it was a fuel injection problem at first
so checked all the fuel sensors and all checked good
then did the caps still intermittent miss
then i decided to check timing and found the timing jump...aka miss
 so then i started checking ignition components
and the timing belt was taken apart to check keyway


before i did any thing i did cap rotor...making sure they were brass...wires, plugs and fuel filter 

then the tps code showed...
so i thought i finally thought i found the issue...nope..
so now i have traced wires made sure they were all good

all the while it has been drive-able very annoying but back and forth to work until November. under acceleration it was fine and idle it was fine...havent driven since i did the tracing and bonding of the coil wire shielding.. (not sure this,, only CMP runs shielded wires and CKP in 1996 up)

fails only hot.  (when, Cruising fast, accelerating or at WOT or when? driving is complex when does it fail and when does it not both, while driving hot)

the fact is the spark timing changes wildly all the time on all EFI engines, but not with timing freeze jumper planted, and not as bad as yours, best I can tell.

we know the ECU does that ,only IT CAN, there are no magic parts inside the distrib, ignitor or coil to do that. (delay, retard-ment is delayed spark, not dead)

the ignition parts (all )can in fact cause spark to DROP out, for sure  hot,  but that is DROP out not a timing change.
has the ECU been RECAPPED or still  running, 26 year old caps there and worse those dang RUBICON black monster known to fail hard.

best I can tell is the ECU is bad or the ECU has an Intermittent sensor of any kind the  fails at random and goes to limphome mode which does cause RETARDED spark grossly.

all inputs to the CPU must not be intermittent, even for 1 second or the ECU will go to limp home mode for that duration.(retarded and super rich misfiring.)

WHAT ABOUT CAPS.  (Be a shame to replace all sensors, distrib, ignitor,spark coil, IAC,IAT,TPS, and O2) just to find the 3 caps that love to fail are bad. a $5 fix.

Caps = electrolytic caps in the ECU , love to fail often even every 10 years in hot geography. (weather)  spec is 20 years at best, 10 is more common.  Rubicon less i bet.
the CaB of the car can hit 200f parked in the hot sun, this is not good for CAPS.

The bad caps cause the ECU to crash and reboot, it is firmware in the ROM (EProm) deep inside that crashes. and  is never ever good to have that happen
it can get so bad the ECU even rattles all relays and VSV like made , key or running. (crashing)

there are only 2 ways to fix bad ECU with bad caps (besides the rebuilts from Cardone 1)
replace them blind. (slam in new caps.)
test them, with ESR meter, and if lucky see them slit open or leaking acid,  but looks do not matter if they look ok, as they do in fact simply DRY OUT inside and are DEAD)

I always had a spare ECU for mine,
after all they do not get  get easier to find, nor in the future.   some of these cars  even have wrong ECU installed, for for sure worst is calif ECU in  FED car, or the reverse .
ECU are no the same for 8v./16v,calif, fed,2wd/4wd , transmissions. and body 2dr/4dr .  (and smog options and year)   The calif ECU has extra ground pin that tells it that the body of car is wired for CALIF and with CALIF sensors. and if missing that ground the ECU set code 53. (wrong ecu)

spare parts to have on this car are , ECU and TB.
those parts hard to find and or takes for ever get hands on,. (down time issues matter?)
and front 4wd axle hubs, not sold now, omg hard to Find.

CAPS good bad or ugly, below is classified ugly to the max , huge damage.  some look perfect and are DEAD and dry inside, the big cans are CAPS. that fail
the huge CORNER caps fail most. this ECU is  now dead forever.(land fill)  the with SIP are saved, and not sold on earth, so those are saved,  BORIC ACID leaked out fast.

[fixkick]

Truth,? In truth all you can do is TEST or guess. (change parts till it runs right)
if  the engine is good we attack EFI. (good vacuum good compression tests) no vacuum bounce nor reverse acting vac with melted CAT and blocking exhaust path.)

This car is not 1996+ so driving and logging all inputs sensors and all DTCs live, is not possible. with OBD1 1995 here.

That means only connecting a wire to each ECU pin 1 one at a time to a portable scope can find the sensor that drops out;  is the only way, in school they teach about break out boxes.

If all inputs are good and the spark  fails, at the coil minus lug, (ECU out) that means the ECU is bad.
If all ECU inputs are good and any out put of ECU is bad then the ECU is bad.
this is true on all computers made those the phrase GIGO, garage in ,Garbage out. mantra.

NO LIE intermittent  problems can be a horror to find. for sure hot and for sure only driving or only under load or only wot ,etc.
I even have digital meter here DMM that has  USB port and I can log data (voltage) to laptop, and test sensors driving.
It (meter above link) is slow to find changes but is far cheaper than any good scope. and does have software that has slow mode scope.)

cheers and happy trails.

[1995 toad]

Did the caps early in the process as I wrote
The distributor has a white wire that supposedly to the ecm it is shielded so i hooked it to ground to see if that helps
still need to see if it made any changes.
and need to test running voltages as you said.

[1995 toad]

well voltage is .5 idling and goes up to 5 quickly still flashing 22 accelerates great idles great and still timing retards intermittently while part throttle cruise.
have no idea..