no FIRE? you mean the coil HV terminal is dead? (Fire is in the cylinders and never at a coil) its called SPARK, or HV. high voltage.
ALL: answers , USA and generic, until engine stated. and nobody fooled with dizzy timing.
which engine, we can not guess that, nor fix or help on NO ENGINE.
my guess is its the 4.0L (1 of 5 million) right?
i guess you are trying to fix a USA car, with no OBD2 $9 scan tool>
really? why do that.?
if you had the tool, and cranked for 5 seconds the tool would show you why there is no spark.
lets do jeep spark 101.. 1993 to NOW
the first steps are:
- fuses good?
- CEL lamp glow key on? if not fuses blown. or worse.
- i connect my scan tool and it communicates good if not , fuse bad.
- I crank the engine and the ASD relay closes, but drops in 3 seconds, (i crank for 5 seconds,) release the key and low and behold this cheap tool shows me DTC error for why.
- did the ASD drop out during the cranking session?
- yes then read why here.
- if the ASD holds, and there are no DTCs shown, then we now check for spark, at all cylinders. 4 or 6 as the case may be.
- got spark on all? no. they are all dead. so i check for spark at the coil HV terminal. it's DEAD.
- I check the primary side of coil, the coil is dead open , infinity ohms.
- I want you to know if the CKP or CMP or coil primary is bad
- the ECU will in fact throw a code (DTC ) for even one pulse in 10 missing. that is a fact. ECU secrets.
read the spark page, ignition. here.
and the schematics at the end.
the coil primary is about 2 OHms (never infinity ohms)
the secondary is about 15,000 (15K) ohms, not zero not infinity
lets now do coil checks (primary side) NO DTC ERRORS right?
ohms passes Homes. (lol)
chapter 8w-30-14 look here.
PDF page 70
a volt meter in hand.
the black (tiny) coil wire is at 12vdc key on for 3 seconds
if not 12v ever, the ASD is dead. you never said it pulls in.
if 12dvc is here for 3 seconds. then the ASD is working
and the PCM is dropping the ASD on PURPOS
E, (use the scan tool)
ok i check the other coil wire,
and it pulses, at 12v 0v and 12vdc, the 0v is very fast.
seeing it pulse takes (major shop tools called a scope)
wire color is GY, (gray?) or green with yell stripe.
but the ECU will in fact warn you if the GY wire is dead.
so we are back to square one, no scan tool for $9
the ELM327 tool is that expensive.
cmp sensor is in dizzy base
CKP is the crank sensor on flywheel left side. at bell.
the ECU monitors the spark at the primary side.
if that fails, it tells you
if the ASD drops it tells you why, with DTCs.
learn to use a dirty cheap scan tool, for this car its dirty cheap.
i use a 3160 at home because it works on all cars.
old and new. best investment but i have 10 scan tools from 95 to now.
or this in a pinch.
a blue tooth tool. for NOTHING
PS do tell what the ASD does, using 2 persons..... it takes 2. on all jeeps. one guy said on his jeep he can feel it close as he cranks