About month ago fuel injector went out. Had it replaced now I’m getting code po455 po300 one large vacuum leak (been chasing the vacuum leak for awhile replaced cats twice evap can and purge siliniode) the other is multiple cylinder misfire. I did have bad spark plug wire I replaced awhile ago just one though not all. Could I have bad spark plugs think first thing change all spark plugs but I’m also getting every once in while red lightening bolt and traction control light on same time I literally about sell this jeep every month something is breaking its 08 jk
Need some help troubleshooting my 2008 Rubicon
- Thread starter Sheldon
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There are a couple other common locations for large evap leak. I had to chase down evap stuff myself when I got mine.
Don't overlook the most common cause: the gas cap. There is also a module on the charcoal cannister called the ESIM which also has an o-ring that can go bad. I had to replace both the ESIM and o-ring to fix mine.
There is also a vapor line that goes into the gas tank that likes to crack:
If you're having misfire issues, just replace your plugs and wires first and then your coil pack. You probably have no idea how old those items are and they're critical to performance.
I had a cylinder 1 misfire when I got mine and luckily during my inspection found (by smearing my greasy hands all over the porcelin part) a hairline crack in it. Used that to my advantage to get another $500 off asking price.
Your traction control light is probably a wheel speed sensor that has gone bad.
These problems probably existed before you bought it, and whoever owned it before you just didn't want to spend money to fix it.
The evap code might be gas cap. If u fuel up with it running it may throw the code . I have an 07 and now turn it off before fueling up for that reason. I had that code about 50 times and always was a loose cap or running when I got fuel . The random misfire is probably plugs , wires , coul. Replace plugs and wires first... then coil
Would be cheaper to have it smoked and diagnosed than throw parts. I also have an 08 rubicon plus run a shop. And yes....needing repair every few weeks is just natural for Mopar. Especially 04ish till 2018ish or so.
The 08 SHOULD say gas cap on the dash where the odo is. Generally they do IF its a gas cap. Mine has. Also generally the code is for a small or very small evap leak if it's just a cap. Usually a large leak code is pretty obvious.
A cat has nothing to do with evap in any situation I've ever seen. Ive seen those come apart and wreck the 3.8 JK though. If you used aftermarket O² sensors that could be a problem. Best thing would be a compression and leakdown test.
151k I wouldn't be surprised by bad plug wires or plugs. If you plan to keep it id be ok with throwing new wires on it. Plugs too.
The lightning bolt is probably a throttle position issue. Be easy to check via a scantool. Never seen it have anything to do with traction control.
Is it just traction control or both stability and traction lights.
Luckily the 3.8 jeep engine is likely the most simple engine made post 2005 or so. No cylinder deactivation. Not even variable valve timing. or much of anything computerized engine wise. Compared to most anything we see regularly nowadays it's a dinosaur so diagnosing it should be easy
The 08 SHOULD say gas cap on the dash where the odo is. Generally they do IF its a gas cap. Mine has. Also generally the code is for a small or very small evap leak if it's just a cap. Usually a large leak code is pretty obvious.
A cat has nothing to do with evap in any situation I've ever seen. Ive seen those come apart and wreck the 3.8 JK though. If you used aftermarket O² sensors that could be a problem. Best thing would be a compression and leakdown test.
151k I wouldn't be surprised by bad plug wires or plugs. If you plan to keep it id be ok with throwing new wires on it. Plugs too.
The lightning bolt is probably a throttle position issue. Be easy to check via a scantool. Never seen it have anything to do with traction control.
Is it just traction control or both stability and traction lights.
Luckily the 3.8 jeep engine is likely the most simple engine made post 2005 or so. No cylinder deactivation. Not even variable valve timing. or much of anything computerized engine wise. Compared to most anything we see regularly nowadays it's a dinosaur so diagnosing it should be easy
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istalvey
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