My 02 Jetta Wagon Build

[Caddylackn]

Get a Scan Gauge II or Scan Gauge E; This will teach you where all your gas mileage drops come from and your mpg gains. Set the gauge up to show boost, instantaneous mpg, and trip mpg. Drive to minimize boost on cruise and accelerating. Run fast downhills to coast. I picked up 20% gas mileage gain just learning to drive with the Scan Gauge.

Leave a good gap in front of you so you can minimize using brakes in traffic.

Following a car 25' behind in the fast lane is the worst for mpg. Lots of acceleration pulses. You want superlight steady pressure on the accelerator.

Don't use cruise control unless its super flat.

Run max tire pressure or a few psi under it.

Check for emergency brake drag and wheel bearing drag. Your emergency brake tightens the rear disk calipers on a VW by rotating the caliper piston when using the e-brake for when the brake pads wear but every time it rotates a click there will be brake drag. I only use my emergency brake once a month or so unless needed on a steep hill.

Aeromods as needed.

Get good new injector nozzles. Old injectors waste fuel. Is your intake clean or gunked up from EGR?

[V6MustangFTW]

I've never owned a euro car before so thanks for the VW specific tips! Brake rotors looked scored so I need to inspect everything brake related anyway. I do have a scangauge 2, but the instant and average mpg functions seems to work intermittently on this car, as noted in my earlier posts. I will check the intake as well and probably run some seafoam or something similar though it.

[V6MustangFTW]

- got a p0420 code yesterday. Previous owner gave me a new cat converter with the car, maybe I should install that?
- warm up times are kinda slow on these cold mornings, and coolant temps seem to settle between 200 and 210, per the scangauge. Would I be safe to insulate and raptor line the underside of the hood to keep things warmer? Anyone know the safe limits of this engine?
- 45 psi in the tires is noticeably harsher than 35 on the notoriously crappy roads around here. Gonna drop them to maybe 42 or 40.
- need to remove rear seat backs, partly for weight reduction but mostly because they dont fold flat and I need the room for the boxes I deliver.
- the cold made my knees hurt, and I'm only 23 glad I got an auto instead of another manual, even if it makes hypermiling harder.
- probably forgetting something, just excited to burn through this tank so I can get my baseline and start modding.
- the car does seem to use DFCO, but its hard to keep it there compared to my stickshift truck. Still, its something to keep in mind.

[Piotrsko]

"P0420 Code: Meaning, Causes & How To Fix It | Mechanic Base
Mar 17, 2023The P0420 code indicates that the ECM has detected underperformance of the catalytic converter's efficiency on Bank 1. It can be caused by a faulty catalyst, or it can be a false alarm caused by a faulty O2 sensor. The engine control module (ECM) uses two O2 sensors, one in front, and one behind the catalytic converter to measure its efficiency."

I wonder why the owner provided a new expensive cat converter.......

Far as I can help, I own a TDI

[V6MustangFTW]

Supposedly he got the converter, changed out an o2 sensor, and that turned the light off so he didn't install the converter... or something like that. He didnt have reciepts so I couldn't really verify any of the maintenance thats supposedly been done. Anyway...
Pulled the rear seat backs out! There's so much room for deliveries and picking up scrap metal now. I wish I had an accurate scale because it was stupid heavy, I swear the passenger side was at least 40 lbs. Also, not an ecomod, but I shampood the carpets to get some funky smells out.

[Christian]

Originally Posted by V6MustangFTW

Hopefully these pictures upload correctly...
Edit: it worked! As you can see she sits pretty low, and I'm already thinking of how to cover the holes in the bumper where the fog light blanks should be.

I recently did some grille blocks on my civic, very cheap and easy mod to do. Very helpful for my city driving as the engine warms up faster. Probably helps with aero too, but I don’t do enough highway driving to be able to notice any difference

[V6MustangFTW]

I have been contemplating how to build an upper grille block, preferably one I can easily remove in the summer if temps get too hot. Warm up times are awfully slow in this car which I know is going to kill my mileage come winter.

[freebeard]

My Dasher came with a sliding fiberboard panel about 4x6" that had a choke cable control so it could be operated from the driver position. It was long gone before I acquire the car.

I have a picture squirreled away somewhere, but DDG can't find it today.

[V6MustangFTW]

Originally Posted by freebeard

My Dasher came with a sliding fiberboard panel about 4x6" that had a choke cable control so it could be operated from the driver position. It was long gone before I acquire the car.

Ive read about other modders here building similar things. Im not sure how I could build one to be flush with the outside of the grille, I may have to dig around and find those old threads for inspiration. I am running up to autozone tomorrow to grab an oil change and hang out with some of my former coworkers so I'll take a look at the choke cables they carry.

[V6MustangFTW]

Ok, so I know I said no mods until after my base tank, buuut the mod bug got me. While I had the headlights off the car to re-clear them, I discovered the Jetta has a cold air intake from the factory. And no, not the "cold air intake" we all put on our cars when we were 16. This is a proper snorkel that goes from the airbox to behind the drivers side headlight to draw cooler air from the outside. I went ahead and removed it since its best accessed with the headlight out. Now its breathing nice warm engine bay air, and I know plenty of others here have proven gains from warm air intakes. Besides that, theres a mesh screen inside it that was completely clogged with dirt and debris.

I also discovered that the upper grille feeds at most MAYBE two inches of the radiator and core support, so I think I'm safe to do an upper grille block, at least in the winter.

Pics are attached.

Oh, and if anyones interested, I can do a quick writeup on refinishing cloudy headlights here, or on whatever subforum is appropriate.