Keeping up with vehicle maintenance is second only to home repairs in both cost and time spent running back and forth “to the store” for something you forgot. This particular adventure started a few weeks back when a “minor leak” turned into a full-scale radiator replacement on my VW. But that… turned out to be the least of the issues.
I knew something wasn’t right the moment the clock struck 4:20 a.m. on Saturday, and I found myself in the garage less than 10 minutes later, about to be elbow-deep in repairs for the next few days. Despite a terrible night’s sleep, I had my checklist prepared: radiator replacement, a faulty cam sensor, and two failed ABS sensors. No biggie. Downing some freshly made cold brew, it was time to get after it.
The ECSTuning all-aluminum radiator I ordered was a pretty easy “rip and replace.” The only snag during installation was having to switch from OE screws to very short 3mm Allen bolts – something I wouldn’t necessarily mind if I weren’t trying to balance the entirety of the front end with any available appendage, all while trying not to lose the bolt and its washers. Securing the A/C condenser, radiator, and front cross-member together took a few tries – and many expletives later, everything was mounted.
The ABS sensors required additional “physical persuasion,” which is customary on any VW of this era. If you don’t hammer and chisel them out, they don’t come out. I only needed to change the ones on the passenger side, but my better judgment said, “Replace them all and save yourself some time.” That said, the left rear was so ornery that it required disassembling the suspension, drilling the 5mm Allen bolt out of the spindle, and devising a new way to remount the sensor. MacGyver 1, Volkswagen 0.
Last on the list was the Bank 2 cam sensor. Again – do you replace just the one or both? I opted for both. Thankfully, on the VR6 they’re relatively easy to access and quick to change.
Meanwhile, I was low on antifreeze reserves, so I decided to hop in my “trusty tow pig” (aka Jeep Grand Cherokee Diesel) and head into town. Good thing – because it was barking at me that it was time to change the oil. Quoting Ace Ventura as the MFD bing-bonged at me, I screamed, “Alllllllrighty then!”
It all worked out, because when we got back the engine would be hot – perfect timing to do a quick oil change while I finished up the VW. I’ll add that part of the Jeep’s oil service also requires swapping out the fuel filters. No worries. We got this!
Fast-forwarding a bit, I wrapped up the VW project and then the Jeep’s routine service. I headed out for a quick test drive. The VW was running great – almost better than before – and I give credit to the new cam sensors. Once I got back, I decided to shuffle the cars around to their normal parking spots and clean up my mess. Upon restarting the VW, suddenly I had a check engine light. We know the jokes: “If a VW has a CEL on, it’s normal.” In my case, I’d thought the bulb was probably burnt out, because I hadn’t thrown a MIL – ever.
A quick diagnostic scan revealed an issue with one of the brand-new cam sensors. After a bunch of “round and round,” I finally decided to put the original Bank 1 cam sensor back in (the one that didn’t need to be changed in the first place), and that seemed to solve the issue.
Later that day, I got a call from GTM’er Porsche Al, asking if I’d stop by on Sunday to take a look at his VW Jetta. He was having an issue where “5th gear disappeared.” Turns out it needs new shifter bushings. Easy enough.
Et tu, Jeepus?
While driving back from Porsche Al’s place (in the Jeep), merging onto the highway, there was a sudden “pop! whoooosh” sound – like the turbo’s wastegate suddenly opened and dumped everything it had to atmosphere – and the Jeep started to lurch. A big red SERVICE ELECTRONIC THROTTLE CONTROL illuminated the dash, and the Jeep went into “Limp Home Mode.”
Never fear! – I’ve actually experienced this before. The TCM went haywire two years into owning the Jeep, and the dealership replaced it under warranty (to the tune of $4,000 that I didn’t have to pay). Dreading that the part had failed again – and that I’d have to pay out of pocket this time – we limped home. Ironically, because of all the diesel #torquems, I was able to keep up with traffic on a Sunday morning, even if the motor was now begrudgingly normally aspirated.
Our goal for the day was to check out the annual “Trunk or Treat” at the famous Carlisle Fairgrounds, home to shows like “Corvettes of Carlisle,” “The GM Nationals,” and many others featured on CollectorCarGuide.net. Figuring I’d need to do some research online to find a new TCM (or turbo) for an 11-year-old, limited-production Jeep, we opted to jump in the VW and head to the show.
We didn’t make it six miles away before it too decided to lurch into limp mode, with more than just a MIL light – the EPC light was flashing vigorously. Again, not one to panic – and not my first rodeo – I knew what this meant too. There’s a problem with the ignition (maybe the other new cam sensor is bad?), but more than likely it’s the throttle body + TPS, as it had given me some heartburn last year but magically “fixed itself.”
We were able to clear the codes and get it to restart and drive normally. Making a U-turn and heading back to the house, we figured we’d call it quits for the day and just watch the F1 race at COTA instead. Dying for a second time about a mile later, I threw in the towel and called upon AAA to tow the VW home so I wouldn’t cause a scene trying to cross town, waiting to reset the system every 15 minutes.
Shoutout: AAA was on-point, and we were hitched up and dropped off in less than an hour of putting in the call.
So let’s do a quick SITREP: both vehicles, in limp mode, with a similar issue. Are they in cahoots? Was there a full moon? Is Mercury in retrograde? What are the chances? And more importantly – which of these do we prioritize fixing first?
After ordering a new throttle body for the VW, I decided to focus my attention on the Jeep. Busting out my trusty Autel diagnostic scanner revealed “Error Code: P0299 Underboost.”
Searching the internet, forums, Reddit, and anything else I could find led me in circles of useless advice, cat memes, conjecture, trolling, misdirection, and responses that make you blurt out in a Captain Kirk voice, “WHAT does THIS have to do with the PRICE of TEA in CHINAAAAAH?” Nowadays, I guess I should’ve just asked ChatGPT and gotten a better answer. All that aside, what I did know is that the “pop! whoosh” sound + underboost code means something in the turbo or a piece in the intercooler system broke.
Not sure how we didn’t notice it, but the problem was actually right in front of us (above). MacGyver to the rescue again – I decided, “I’ll make a bracket to hold it from coming off…”
I didn’t even make it past GTM’er Sam H’s house (less than two miles away) when “pop! whoosh” goes the weasel. #limpmode MacGyver 0, Jeep 1
There are lots of terribly designed components out there, and I don’t want to play the blame game. This isn’t 100% Chrysler’s (/Mercedes’) fault, nor the CXRACING aftermarket intercooler kit. This junction is designed for a specific type of connector, which makes it hard to work with. But! It’s been trouble-free since 2021 with the silicone + turbo clamp setup. Obviously, not anymore.
Deciding that this was never going to get better, I went back to the OE pipe and created my own “hybrid solution” to what could become a nagging problem. After some more expletives, gentle persuasion, and some much-needed direct heat, I was able to adapt the pieces together. Time to clear the codes and try again!
MacGyver 1, Jeep 1. The score is even, but after 10+ miles of spirited test driving, this new setup is holding – and the engine feels stronger, probably since boost isn’t eeking out of the system right before the throttle body.
So far, so good. But I’m still leery and will have to build up my trust in the Jeep again. And I think that’s part of the lesson learned: you can keep up with all the maintenance, check and re-check everything, but like Monty Python’s Spanish Inquisition – there’s always something unexpected that will catch you by surprise. And problems don’t fix themselves!
Even when you know they’re fixed, there’s a period of lingering “mistrust” between you and your vehicle. It might be all psychological, but that feeling of “betrayal” is very real. Stings a little. Smarts a lot.
More to come, as we wait for parts from the Black Forest before getting the VW back on the road.
