Top 20 1999 Jeep Wrangler Questions & Answers

You will need to scan the PCM for stored faults. The PCM will receive the resistance value from the fuel sending unit and sends this info via the data bus to the instrument cluster. There could be a wiring issue from the sending unit to the PCM, so I would do a resistance test on the wires to check for continuity.

1999 Jeep... | 99 views | 0 helpful votes

I think you could use this manual method instead.. My nephew used it to repair my car and it's perfectly fine now. Here's the website
he bought it from.

1999 Jeep... | 183 views | 0 helpful votes

Check fuse 18 in the box under the hood. If yhat is good, suspect the crankshaft sensor. If you can scan the computer, send the trouble codes.

0996b43f8023b434-yp0qq50ufpnkyh0vkygowrgc-5-1.gif ?

1999 Jeep... | 87 views | 0 helpful votes

Visit the on-line store, known as reliable-store, they have the repair manuals. I'm sure you will get the solution of your problem.
1999 Jeep Wrangler

1999 Jeep... | 65 views | 0 helpful votes

harmonic humming ( harmonic vibrations ) indicate a problem idler pulley bearing , water pump bearing , alternator bearing or power steering pump bearing It is not considered an ac compressor bearing because when the ac is energized that pulley bearing stops spinning when the shaft starts turning and you state that the hum persists with ac on or off

1999 Jeep... | 29 views | 0 helpful votes

Hook up a scanner and find the problem. Make sure that the injectors are pulsing. Water could have blown a fuse.

1999 Jeep... | 80 views | 0 helpful votes

Due to the age of your jeep, You need to replace the fuel pump and filter along with replacing the water pump and thermostat as well as coolant temp sensor. Fuel supply and coolant flow and temp sensing is critical to Cold start (open loop) and warm up (closed loop) Idle function and fuel mapping. Change the air filter too.

1999 Jeep... | 26 views | 0 helpful votes

the pcm is suspect in that year jeeps. simple easy test. locate pcm usually on firewall passenger side under hood. 3 large cables going into it on most. start jeep. let it idle. wiggle one wire at a time. does it shut off?? bad pcm solder joints inside are broken. doesnt shut off?? another issue to be determined.

1999 Jeep... | 41 views | 0 helpful votes

not normally
there may be metal flakes in the filter in the reservoir so replacing it would be a good idea
don't bother repairing the pump, it will be more cost effective to get a new one
if short of cash , get a good unit from the wreckers/ junk yard

1999 Jeep... | 348 views | 0 helpful votes

Possible water pump bearing. Maybe anything. If you push on the clutch and it is still there, when in gear, it is nothing to do with the gearbox or transmission.

1999 Jeep... | 161 views | 0 helpful votes
manual trans or automatic, the are not the same.???????
so fix when not starting, afterwords that can be impossible
to fix this, scan it
the scan tool will tell why it lost spark
p03xx errors
do not play with CKP sensor,if you remove, it and not put it back like the FSM states, it will never start or be damaged
it has critical gap there. (see fsm exception)
there are 3 eCU inputs that kill spark
dead cmp
dead ckp'
and dead tachomter, ignitor signals,
all 3 , will kill the ASD relay dead, (6 ways) (scan it)
this fact , is why we scan ,and not guess.
if you install a new ckp , and do it wrong, its destroyed in some cases.

to read how to do it right (ckp)
read the free fsm

WE HAVE 100'S OF posts here,making the CKP install error.
click ignition chapter
8D-12 read page 13
one 2.5l has a special machined sensor that fits with out adjustment. if you read that page 13, it covers a/t and m/t
rules. (2 engines, 2 trans) rules.
and if you buy autozoned parts,they will sell you that wrong part
toss 4 sided coin bam fail.
One sensor has glued paper sensor gapper, that must be used.
CKP have gaps that must be correct. keep that in mind and all works out. via the FSM.
all none HALL sensors are like this, (tuned with a gap)]

only how done varies.

1999 Jeep... | 122 views | 0 helpful votes

i would think that it is an immobilizer symbol letting you know of a problem with the key in use
talk with a service dealer or have the fault codes read to see if there is an immobilizer fault

1999 Jeep... | 261 views | 1 helpful votes

read that on the door jam label .

1999 Jeep... | 239 views | 0 helpful votes

which engine, we cant guess them here.
the TJ book is free.
the real deal ,even full schematics and every wire color !!

no spark on all cylinders or just one.
if coil is dead, sure,

this is and EFI engine,not some simple 1980 CJ.SORRY!

the EFI has many things that need to work to run.
not just one wire.
the cranking is simple, (old , tried and true, simple)
but not EFI.
so do you have tools, i mean voltmeter and a scan tool>?

if you connected the scan tool and cranked 99% of time
(new engine, new sparkplugs,new wires there)

the PCM will tell you what sensor is dead preventing spark
there are 4 causes. ill list them.
cause one is fuses blown
cause 2 CEL lamp dead. in cluster, means PCM has no power see number one cause fuse. CEL means check engine lamp....
it glows key on , telling you, hey buddy ECU has POWER.

If car is fitted with factory immobilizer , is the dash lamp glowing telling you its Immobilized?
when you crank does the ASD relay close for 3 second min?
fuse 12,6, and 18(coil)

now the sensor side.
1: CMP dead. P3xxx codes. DTC's
2: CKP dead (crank sensor)
3: ignitor dead. (it drives the coil)
4: tacho line dead. (some times is just #3)

hint 2
if the ASD does not close (energize) or closes for 3 second
and drop out
for 100% sure the scan tool tells you why it fail.
not scanning modern cars , you will work blind and fail.
big time. a tool is as cheap as $10 (real scan tool not a bs code reader)

if the scan tool (used) , shows no DTC errors??? live?
cranking for 5 full seconds?
fuse 18 blown or coil is bad.
1 min flat, you know.
the below is off the link above. in the wiring section
chapter 8w-30
fuse 18 top left must be good.
the ASD relay must close.

25836061-b0qotdfot4r50rcgu1whx1iy-5-0.jpg if the scan tool show these errors
see the ASD page, for way.
no starts, or only runs 2-3 seconds, bingo

DID i cover this fully? if not ask.
can do each step 1 by 1....

1999 Jeep... | 163 views | 0 helpful votes

great post. but no engine stated. 2.5L? 4.0L?
  1. what is rpm at idiott lamp on? 800 or 400?
  2. what oil, 0w?
  3. how old is oil, 6months 6 years.?
  4. use a real pressure gauge yet, to see if switch is bad?
  5. the switch on most cars can come on 3 -5PSI (its a useless device really, as that is WAY too late a warning , IMO
  6. use a real test gauge in place of the switch ? for testing or full time on a Tee fitting, or get a real gauge that has programmable trips.

1999 Jeep... | 128 views | 1 helpful votes

Jeeps most common problem is with these particular vehicles are the crank sensors. May also have a bad reluctor. which is part of the flywheel. What you need to do first, Need to first remove the crank sensor which is on top of the bell housing. Remove it and inspect for cracks if you see any cracks replace it. and reset gap. You can use a small piece cardboard like the thickness of an oil filter box,tape it to the tip end of the sensor,and reinstall. After inspection or replacement of the sensor, start vehicle,Also keep an eye on your tachometer . Your tachometer should slightly come up when cranking. If not replace sensor.The crank sensor is a part of the ignition system, the pcm needs to see where top dead center is or where #1 cylinder is to determine when to spark, simply put. So the pcm knows when to fire.

1999 Jeep... | 141 views | 1 helpful votes

I think your 2.5 still has a distributor...check for a cracked cap, or cracked rotor...same symptom...hope this helps.

1999 Jeep... | 120 views | 0 helpful votes

you should talk to a jeep spares department for the conversion parts or cruise around the wreckers for a wrecked soft top jeep for the parts

1999 Jeep... | 125 views | 0 helpful votes

well first is the fuse. (if all else works ok, not stated)
no shorted bulbs, they can short. like that. and blow fuse.
the free book is here, see TJ? 1999
see last line WIRING, click that?
id work brakes first, 10x more simple.
see page. ,8w-51-4 (pdf page 134)

see fuse 2? brakes
it feeds brake switch .
id bet the fuse is blown,
if blown remove 4 lamps , blow now, wirnng shorts rear. (hitch hacks)
if not blown check wire, white-tn (tan) for 12v when brakes are applied, if 0v move forward do switch, brake,
the point that has 12vdc on one side and 0v other is bad.
wire, connector or switch.
if voltage is found to be low, that is a short.

1999 Jeep... | 103 views | 0 helpful votes

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