One November '23 Friday afternoon my wife, aiming to take our kids for the swimming lesson, attempted to start the van. Tick & flash, but no start! Blaming the battery at first, or two batteries to be precise, I put the car on a trickle charger. No help. Our van comes with the universally hated, rightfully so, most useless gimmick: start & stop system. It saves zero drops of gas at the cost of maintenance and reliability issues to the owners. As I did not have spare cycles to debug the issue, I called in for a "professional".
Mobile mechanic diagnosed a burnt starter, which was almost completely wrong: it was a symptom. OK, it may have been the burnt starter, but also the 150A main fuse (yes!), TIPM and all of that caused by the engine being hydro-locked. The root cause being a blown head gasket, which somehow the mechanic completely missed. I guess it did not read on his Pip-Boy, so he felt lost.
Extensive forum search, polling Pentastar engine owners for common failure modes and my own diagnostic revealed we could be facing a catastrophic engine failure.
After re-charging both batteries and many failed attempts to start the van I began researching common failure modes of the infamous Pentastar engine. Knowing it could be a burnt starter narrowed down my search to a ... drum roll ... head gasket failure and a subsequent hydro lock. In a video where a mechanic has turned the crank with a wrench he found water (coolant) in the oil pan and as he turned the crank water could be heard flowing inside the cylinder, which is the confirmed hydro-lock. After taking a sample from the bottom of the oil pan and pulling out the spark plugs one by one this issue indeed affected our engine. It is estimated about 0.5% Pentastars suffer from the same fate, meaning 1 in some 200 Chrysler 300s, Jeeps, Pacificas, etc. Sounds like a lot! Shops are quoting upwards of $5000 and no remaining warranty on powertrain on ours. It expired in early 2020 as a "certified pre-owned". What a joke!
Facing these options in the order of preference:
- roll it down the hill: insurance would like breathe on my neck
- have it fixed by a shop: expensive and the car was inaccessible for a towing truck anyway
- swap the engine: more work than I was ready for, besides risking the same issue all over again
- fix it: well ... f*ck, there go my evenings and weekends
In order to debug the electrical issues, I needed a wiring diagram. Chrysler makes you pay a subscription fee for access and there is no printed service manual. I hated Mopar more and more each day, I am also convinced this is my last car ever made by Chrysler. The stupid expensive wiring diagram lead me to a discontinuity inside the TIPM itself. Quick and dirty hard-wire test confirmed the van now indeed starts, yay! I kept the leaky cilynder without the spark plug to prevent further damage.
Now off I go and ship the TIPM to a specialty service in California to fix it. In about I week I got it back only to find out they did not do jack. Apparently their extensive testing harness is worth two rat poops, but I gave them another shot. Obviously they came back to me in about a week again only to find out my broken TIPM tested just fine. Anticipating their incompetence I ordered a replacement TIPM from a wrecked Pacifica on eBay and guess what! The eBay one worked, the double-checked and double-fixed one from California didn't: refund and review time.
These are the hard-wire start videos, hence the odd sound and all kinds of oil / coolant mix smoke:
At this point I briefly considered blue / green / etc. chemical gasket fix agents, upon a deeper dive on this topic and learning about the origin of those agents, I returned all of the goblin colored bottles and went back to replacing the head gasket plan. I found a professional shop video, where the engine was out of the car and it still took 24h of shop time. Beginning to doubt I'll even finish this job, I started the struggle of removing the timing cover. What a *ich! The goo just would not let go and trying everything short of prying, I resorted to heat gun and slow pull with ratchet stripes tied to our neighbors fence posts.
The above photos are a bit out of order, obviously the head on my workbench was meant to be the pinnacle of disassembly. Anyway - after the Action Machine shop confirmed it was good to go, cleaning and assembly began.
First start did not go well at all. My wife was filming, holding a fire extinguisher too. She may nearly needed it too, since I installed the injector rail incorrectly and there was a huge fuel leak, scary!
Injector rail re-seated and it came back to life! The smoke was unsettling at firs, luckily cleared with subsequent runs and warm ups.
The smoke cleared eventually, it's the oil and coolant burning out. Had my asssembly checked by my local shop, other than rusty break rotors cause by Seattle winter and six months of downtime, bad oil cooler aftermarket seals and coolant flush, no major work required. Yay! All and all I spent about $2500 on labor and parts and another $2500 on our backup car. Same as the original quote, which would totally run over and I got an extra car!
Technically completed in April '24, we did not start regularly using the van again unil late May '24, because the interior caught mold during the Seattle winter. Had it professionally cleaned and detailed and all with the new car smell it came back to service.
Happy end! As of January '26 the car traveled another 15k miles on its own power, no issues.
