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2006 DTS VIN Y
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Discussion Starter · #1 ·
I’m having the dealership do this for me next week. I’m second owner so I don’t know if it’s been done. I get the po420 code about once every 6 months(bad gas?). Vin falls below like you said. 68,000 miles all highway. I sure hope this keep the check engine light out. 06 dts

My 2006 DTS gets the P 0420 code about every 6 months. 4 times. 65000 highway miles. I understand that there is a reflash or update for this car concerning that code. My car falls under the threshold that I read on here somewhere. I made an appointment at the dealership to get it updated. I’m the second owner so I don’t know if it’s been done already. Looking for insight on how to handle this. I’m almost sure it’s the solution! What exactly should I ask them to do???? Thanks
 

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2002 F55 STS, 2014 Explorer XLT, F-150s
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If the TSB/recall is still active the dealership will have the procedure on file.

It's probably not "bad gas" in your Charlotte area - it's the after-cat O2 sensor reporting low cat converter efficiency.

Check the oil level and fresh gasoline - get out of town to a deserted section of road - No traffic? Put the gear stick in 1 and floor it up to about 75 - 80 mph. You WILL NOT break anything - the 4T80E is smart. The car will accelerate, shift to 2nd at redline, shift to 3 at redline, you flip your foot off the gas and let it coast down to < 10 mph. Lots of black smoke during the acceleration? Do it again.

Read this - all of it - written by a CF member who was a GM/Cadillac Northstar powertrain engineer. Especially the section titled "Occasional full throttle operation is good ..........".


What is the 8th character of your VIN - 9 or Y? It makes BIG differences in some powertrain, parts, service, and maintenance advice.
 

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2002 F55 STS, 2014 Explorer XLT, F-150s
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Boats, when, where?

New London, Charleston, Naples (Italy), Rota (Spain), Kings Bay -

Up to mid-'74. more later - went to Fleet Reserve on 26 in '82

Sleeve Collar Font Screenshot Uniform
 

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2002 F55 STS, 2014 Explorer XLT, F-150s
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I was USS THOMAS ALVA EDISON SSBN 610 gold. Sonar
\
When I was in SAM HOUSTON (SSBN 609) during the Charleston SC overhaul in '73 -'74 I swapped with QMCS Beasenburg in POLK because I wanted to stay in Charleston and HOUSTON was going to Guam post-overhaul. Quartermaster / COB - both boats.

Retired as Command Master Chief, U.S. Naval Academy.

DBF -
 

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Discussion Starter · #10 ·
When I was in SAM HOUSTON (SSBN 609) during the Charleston SC overhaul in '73 -'74 I swapped with QMCS Beasenburg in POLK because I wanted to stay in Charleston and HOUSTON was going to Guam post-overhaul. Quartermaster / COB - both boats.

Retired as Command Master Chief, U.S. Naval Academy.

DBF -
Great video !!! I have a few more questions bout my DTS.
1. I guess AC Delco is my go to for brake pads.
Do you have the part numbers for front and
Rear. Gonna do them myself. Not quite sure if
I have abs.
2. I have no coolant leaks. My car does fine on
The highway temp wise but occasionally it
Wants to run hot light to light. Seems to me
Like a sticky thermostat. I ran my heater at 90
Degrees with a light fan to try and burp the
System of air last night. Do you know the
Correct part number for my thermostat?
3. Does the TSB/recall have a number I should
Ask for relating to my code po420??? My
Appointment at the dealership is Tuesday
Morn.

This is a great car! It was only driven 12000 miles from 06-2018. I got married and moved to SC shortly after I bought it. I’ve been driving up and down I-77 to work and back for 4 years now it has 68000 and needs some work. I really appreciate your help COB. My last car was a 1998 Eldorado.
 

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2002 F55 STS, 2014 Explorer XLT, F-150s
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The brake pads can be sourced from RockAuto oe www.placeforbrakes. I happen to like the EBC Redstuff ceramics - tough, quiet, smooth after break-in.

The 'stat is set to begin opening at 188 and fully open at 206. A Northstar in good condition runs at 190 - 205 all day every day. Yes, with no A/C compressor function set the temp gauge will move toward 224 in traffic. With an A/C function, including DEFROST, is set the fans run in SLOW - not for cooling but to insure airflow through the condenser at slow vehicle speeds. 'stats in RockAuto - Stant, DAYCO, Gates, "AC Delco" - all the same one. Very reliable, probably not a problem even now.

Slope Font Astronomical object Circle Science


As far as the emissions TSB you might find it with a Google search for something like "cadillac deville northstar emissions tsb" or something similar, maybe inserting "p 0420" in the search info title.

The P 0420 TSB for my 2002 STS is 03-06-04-028 of 05/15/2003.
 
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