Okay so I washed my car a few weeks ago and the Slow Down Light came on. Heard that moisture in CTU can cause this. Turns out I had a broken clamp and an exhaust leak which I fixed. Car is a 98 with headers, high flow cats and a capristo bypass valve. Car was running really well with no issues for last year since major service. Right now I am getting the following OBD 2 codes: P0153 O2 sensor circuit bank 2 sensor 1 P1449 Catalyst temperature bank 2 And the following pending codes: P0159 O2 sensor circuit bank 2 sensor 2 P1451 Secondary Air Pump Circuit P1448 Catalyst Bypass Valve Circuit I have erased the codes once but they came back. So what next? Do I replace the bank 2 Catalyst CTU? P/N 160454 I hear these things are problematic. Any thoughts would help.
Have you tried the dry washes? If all these happened after you washed your car, then we can assume that you got water in a few places. 1. Remove the side cover in the engine bay 2. Disconnect the various connectors at the left hand side that go to the 2 O2 sensors and the bank 2 TCU 3. Blow them out with compressed air to clean any water in them 4. Might as well repeat on the right hand side 5. Crawl underneath the car, right hand side, behind rear wheel well 6. Disconnect TCU connectors, one et a time, and blow them out with air 7, Disconnect the 2 connectors controlling the bypass valve and injector valve, Blow those out with compressed air Reset, drive, and see what happens You may need to replace O2 sensors on bank 2 and TCU on bank 2, especially if it is still the black one.
Unless your O2 sensors are installed in such a way that they point up, I doubt you have water in them but anything is possible. I wet wash my car constantly and have no issues.
Are the CAT ECU's black or green? If they are black, they are old and may have been cracked prior to the washing. Green ones may now be required. I wash my car form time to time and have driven ion rain a few times as well without issue....but I swapped all three CAT ECU's to new ones 4 years ago.
If you plan to replace the TCU's, I'd suggest you install the aftermarket ones made by Goth and sold thru Ricambi.
Water in the O2 sensor connectors to the engine harness, left hand side, mounted to the upright member of the subframe.
That's great but don't crack open the champagne yet - you need to clock some miles to be sure the codes won't reappear
FWIW, I had one of the small hoses to the expansion tank start leaking. After I replaced the hose, I washed off the spilled coolant on the front of the motor, to get the coolant off of the belts. Every time I would go around a hard right turn the engine would stumble and throw a light, and after a few seconds it would go away. It turned out to be the connector at the crank sensor. It was filled with water/coolant! My cats and Ferrari dont enjoy baths.
