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What P0302 means for your Jeep Grand Cherokee
Your Grand Cherokee's ECM detected that cylinder 2 isn't firing properly - the crankshaft position sensor saw the rotational speed dip slightly each time cylinder 2 was supposed to combust. On the 5.7L HEMI Grand Cherokee, P0302 is often the famous HEMI MDS lifter failure or a dropped exhaust valve seat. On the 3.6L Pentastar, P0302 is usually a left-bank cylinder head failure (a known issue on 2011-2013).
🎯 Top Causes on the Jeep Grand Cherokee
45%
#1 CAUSE
HEMI MDS Lifter Failure (5.7L)
The 5.7L HEMI uses Chrysler's MDS (Multi-Displacement System) - the same lifter-collapse technology as GM's AFM. The MDS lifters on cyls 1, 4, 6, 7 are prone to collapse after 80k miles, but the resulting cam wear can spread misfires to non-MDS cylinders including cyl 2. Symptom: tick at idle that gets louder warm, intermittent or steady misfire, sometimes a cold-start tick that goes away. Fix is full lifter and (usually) cam replacement plus MDS-delete tune.
Lifter Set
$250-$450
Cam + Lifters
$500-$900
Shop Repair
$2500-$4500
30%
#2 CAUSE
Dropped Valve Seat (5.7L HEMI Eagle)
2009-2018 5.7L HEMI Eagle engines have a documented exhaust-valve-seat drop problem - the seat works loose and falls into the cylinder, instantly destroying the piston. Early warning is a sudden hard misfire on a single cylinder with low/zero compression in that cylinder. If you have P0302 with a dead compression test, this is likely - and the only fix is a cylinder head or short-block replacement. Chrysler extended warranty (W77) covers some VINs.
Compression Test
$80-$150
Cylinder Head
$1200-$2200
Short-Block Replace
$5000-$8500
25%
#3 CAUSE
Pentastar Left-Bank Cylinder Head (3.6L 2011-2013)
2011-2013 Pentastar V6 engines have a documented left-bank cylinder head defect - a valve guide / seat issue causes cyl-2 (left-bank front) misfires that won't respond to coil/plug replacement. Chrysler issued recall N49 / customer-service action covering many VINs for a free left-bank head replacement up to 10 years/150k miles. If your VIN qualifies, the fix is free.
Recall (qualifying VIN)
$0
Left Head + Labor
$1800-$3000
Compression Test
$80-$150
🚗 Most Affected Grand Cherokee Model Years
| Year | Engine | Primary Cause | Typical Mileage | Notes |
|---|---|---|---|---|
| 2011-2013 | 3.6L Pentastar V6 | Left-bank head defect | 60k-130k | Recall N49 covers many VINs |
| 2005-2010 | 5.7L HEMI (early) | Coil / MDS lifter | 80k-140k | Pre-Eagle, fewer seat issues |
| 2009-2018 | 5.7L HEMI Eagle | Lifter + seat drop | 70k-130k | Worst combination of issues |
| 2014-2020 | 3.6L Pentastar (post-recall) | Coil / plug | 70k-130k | Head issue largely resolved |
🔧 How to Diagnose P0302 on a Jeep Grand Cherokee
- Run a compression test on cyl 2 first. A dropped valve seat shows 0-30 psi (catastrophic) vs healthy HEMI 170-220 psi. If compression is dead, stop and budget for a head or engine job.
- Listen for an MDS lifter tick on the 5.7L. Cold-start tick that goes away = MDS lifter on the way out. Persistent tick warm = collapsed lifter. Tick + misfire = act now before cam damage spreads.
- On the 3.6L Pentastar, check the VIN against Chrysler recall N49 (left-bank cylinder head). If covered, dealer fixes for free. If not covered, swap the cyl-2 coil and plug first; if misfire persists, leak-down test the head.
Want a step-by-step walkthrough specific to your Jeep Grand Cherokee? Run a $5.99 AI diagnosis report - we narrow the cause to your year, engine, and symptoms.
❓ Frequently Asked Questions
Is my Grand Cherokee covered by the Pentastar head recall?
2011-2013 Grand Cherokees with the 3.6L Pentastar may qualify under recall N49 / customer service action - the dealer will replace the left cylinder head free up to 10 years or 150,000 miles. Run your VIN at jeep.com/recalls or call 800-853-1403.
How can I tell if my HEMI dropped a valve seat?
Symptoms: sudden hard misfire on one cylinder, often after a heat-soak; sometimes a metallic ping then dead miss. A compression test on the affected cylinder will read near zero. A borescope through the spark plug hole shows damage to the piston crown. If you see this, do NOT keep driving - debris will spread to the cam and other cylinders.
Should I do an MDS delete on my HEMI?
If the truck has under 80k miles and no current lifter issues, an MDS delete tune ($300-$500) plus MDS solenoid blocker kit prevents future lifter collapse. If the truck already has a lifter tick, you need to fix the damaged lifter/cam first - delete is secondary.
How much does HEMI lifter replacement cost?
DIY (10-15 hours, requires intake removal and cam timing): $400-$700 in parts. Shop: $2500-$4500 if no cam damage, $4000-$6500 if the cam is worn. Add $500 if you do an MDS delete and tune at the same time (worth it).
Which cylinder is cylinder 2 on a HEMI?
Chrysler HEMI V8s: cyls 1-3-5-7 on the right (passenger) bank, cyls 2-4-6-8 on the left (driver) bank. Cyl 2 is the front-most cylinder on the driver side.
See all P0302 causes (all vehicles) → · Related: HEMI MDS Lifter Failure →