Hello Guys,

 

Today, after I swapped one of my front tires with one on the back, to find the culprit in the steering wheel vibration (more here) I decided to go on the highway, while moving through town felt a violent car shake, and I blamed it on the wind, I was at the peak of a bridge.

Everything went fine, I went up on the highway, and then 5 km in, the Glow Lamp MIL started flashing , and the car started shaking, more violent when accelerating and I was losing power, I entered limp mode with 50 km/h max (barely).

I got off the highway parked where I could and just let it cool, then started again and went off and it was fine, but started again after 5 minutes, and I limped another 5 km back home.

At home, I plugged in my OBD and got the P0203, I opened the cover and messed around the plugs a bit, and then the shaking and flashing went away.
To test it, I went back on the highway, and 20 km in, it started doing it again, pulled over, pulled and pressed the plugs again, and went off.
But it was not responding as it used to, so I just stayed at 90 km/h and went back home.

When I got back I plugged in my VCDS cleared the codes, and tested again, but this time there were no P0200 codes anymore, so I started messing around with the plugs some more.

I've now gone on a 10km trip on the highway with high speeds and haven't had any issues, but I do feel some vibrations when accelerating, and I am starting to wonder if this may be the same culprit I was chasing in the post above.
 

The car now runs OK I would say but it's a bit more shaky than normal, or maybe it's just me, but something tells me this issue is not over yet.

I would LOVE to take the plugs out and clean them then, maybe there is a bad contact, but I haven't found ANYTHING online, there must be a tool or a DIY way to take them off...

 

I've also

 

 

I've also read that the brake light can cause a similar issue, but after clearing the fault, it went away, the fault was there because I changed some dim bulbs yesterday.

 

 

Any help would be appreciated!

Edited 21 December, 20232 yr by Shaiogded

Hello ALL.

 

Despite receiving no replies, I am compelled to share the solution I've discovered for the benefit of anyone encountering a similar issue in the future.

Following the replacement of the EGR and intake manifold due to substantial carbon deposits, the problem persisted, albeit with less frequency of triggering limp mode.

However, with warmer weather towards the end of January, gradual improvements became apparent.

Even when faced with cold mornings, the car had no issues.

 

Yet, my confidence in its reliability remained shaky, particularly as it would occasionally stall during highway acceleration attempts, prompting further investigation.

 

In a curious turn of events, after getting a rescue cat from Facebook and subsequently taking it to the vet due to mouth odor, upon returning to the car, I noticed the "Check Rear Left Foglight" MIL illuminated.

A simple tap on the light module miraculously resolved the issue, sparking my curiosity.

 

Reflecting on the timeline, I recalled that this entire saga began the day after navigating heavy fog on the highway, prompting me to replace the fog lights, which appeared dim.

 

So I visisted the dealership and asked them to check the wiring on the read lights, as juttering the lightbulbs did not produce any effect, other than turning them on sometimes.

Upon revisiting the dealership, it was discovered that they mistakenly inspected the front fog lights instead of the rear ones.

 

While awaiting an electric diagram from the dealer, impatience led me to inspect the car's rear thoroughly. Surprisingly, no anomalies were found everything appeared intact.

However, upon closer inspection, one fog light was found to be completely non-functional, with two position lights exhibiting a blackened tint.

To err on the side of caution, I replaced all twelve light bulbs, leaving no room for uncertainty.

 

After this, I embarked on a 600 km journey with the car, encountering no issues whatsoever.

Even during aggressive accelerations, the car operated perfectly.

 

In retrospect, it appears that the ECU's erratic behavior was triggered by the presence of one or two nearly burnt-out light bulbs, a seemingly minor issue with significant consequences.