cadillacjeff7777 Posted September 2, 2014 Report Share Posted September 2, 2014 Ok, I'm about to trade off this DTS as I am getting sick and tired of it having issues. My 93 Seville was sold at 160k without having a problem. My 95 SLS was totaled at 336K without having a problem. This thing has 130K and has weekly issues from water pump to radiator cap to washer fluid sensor to seat heater module to spontaneous messages about servicing the anti-theft. Now the CEL is lit. How do I pull the codes out of this thing? It used to me some two button combo and the DIC would start spitting them out. I don't remember the procedure. 2008 DTS Link to comment Share on other sites More sharing options...
cadillacjeff7777 Posted September 2, 2014 Author Report Share Posted September 2, 2014 AZ scanned it. P0174. 2008 DTS Link to comment Share on other sites More sharing options...
Texas Jim Posted September 2, 2014 Report Share Posted September 2, 2014 AZ scanned it. P0174. Tighten the intake bolts... they are probably loose... Link to comment Share on other sites More sharing options...
KHE Posted September 2, 2014 Report Share Posted September 2, 2014 Check the rubber intake plenum - there is probably a split on the bottom. Not a hard or expensive fix. The last year for the onboard diagnostics was 2005. Kevin '93 Fleetwood Brougham '05 Deville '04 Deville 2013 Silverado Z71 Link to comment Share on other sites More sharing options...
cadillacjeff7777 Posted September 2, 2014 Author Report Share Posted September 2, 2014 So it's not an O2 sensor? The wife said that's what the AZ employee told her. 2008 DTS Link to comment Share on other sites More sharing options...
Texas Jim Posted September 2, 2014 Report Share Posted September 2, 2014 So it's not an O2 sensor? The wife said that's what the AZ employee told her. It actually means that it is LEAN on bank 2... The intake bolts are known to work loose over time and can cause that... that's why I mentioned check them before spending any money on stuff that may not be needed. Link to comment Share on other sites More sharing options...
cadillacjeff7777 Posted September 2, 2014 Author Report Share Posted September 2, 2014 It might be worthy to note that last December the water pump seized. The dealer that worked on it broke a tube on the intake manifold and replaced it with a salvage intake. 2008 DTS Link to comment Share on other sites More sharing options...
cadillacjeff7777 Posted September 2, 2014 Author Report Share Posted September 2, 2014 Does anyone know what the torque specs are for the intake bolts? 2008 DTS Link to comment Share on other sites More sharing options...
Texas Jim Posted September 2, 2014 Report Share Posted September 2, 2014 Does anyone know what the torque specs are for the intake bolts? I don't know the exact torque... but they are small bolts...so not very much. I used 1/4" drive ratchet and socket on some of them and a little wrench on a a couple of them that I couldn't get to with the ratchet and just snugged them down good. Since they are going into aluminum, I didn't want to strip one out... Link to comment Share on other sites More sharing options...
KHE Posted September 2, 2014 Report Share Posted September 2, 2014 I think the spec is 89 INCH-lbs. Kevin '93 Fleetwood Brougham '05 Deville '04 Deville 2013 Silverado Z71 Link to comment Share on other sites More sharing options...
airmike Posted September 2, 2014 Report Share Posted September 2, 2014 KHE is correct 89 inch pounds according to service manual Link to comment Share on other sites More sharing options...
barczy01 Posted September 3, 2014 Report Share Posted September 3, 2014 You never know who will be working on your car at the dealer. Today will it be the veteran tech or the hungover 24 year old that doesn't want to not be there at all but he has a kid on the way. I stop by the local dealer I worked at when I moved here from Washington D.C. and the stories are not funny. Link to comment Share on other sites More sharing options...
cadillacjeff7777 Posted September 3, 2014 Author Report Share Posted September 3, 2014 If the problem is resolved, will the CEL remain lit until it is reset? 2008 DTS Link to comment Share on other sites More sharing options...
Texas Jim Posted September 3, 2014 Report Share Posted September 3, 2014 If the problem is resolved, will the CEL remain lit until it is reset? It should go out after a few driving cycles... or run by AZ again and if they can reset it. Link to comment Share on other sites More sharing options...
cadillacjeff7777 Posted September 4, 2014 Author Report Share Posted September 4, 2014 Ok...I need some educated guesses here. I took the car to AZ to clear the codes. They do not clear codes anymore. The guy told me that AZ got sued by someone and has since ceased clearing codes. They will read them. Anyway, he plugged it in and highlighted "Erase codes", handed it to me, and told me that if enter were pressed, the codes would be cleared. The CEL remained off for the 6 mile drive back home...But I checked the Avg. Economy on the DIC and it has dropped from 20mpg to 18.3mpg. I asked the wife about it and she said that it has been getting bad mileage for a couple on months...So something is definitely going on. The car has 130,429 miles on it. Here's what I have done. I have checked all of the 10MM intake bolts and they feel snug. The rubber pipe to the air filter housing looks good and the two hose clamps are tight. Intake replaced with salvage part last December with new water pump. Oil changed with M1 EP 15k oil and M1 EP filter religiously when OLM reaches near 0%. Transmission fluid and screens cleaned at 80k (20k early). Here is what I have not done. Replace the spark plugs. Replace the timing belt. From the poor mileage it is obviously running rich. Could it be an O2 sensor that has been weakening causing the car to increase the fuel (due to reading lean) and finally the CEL came on when the car could no longer compensate for the erroneous reading? Could it just need new plugs? 2008 DTS Link to comment Share on other sites More sharing options...
Eldoradoman2001 Posted September 4, 2014 Report Share Posted September 4, 2014 Plugs should be replaced, reset the avg. economy and check it again,and the Northstar has no timing belts just chains!! Link to comment Share on other sites More sharing options...
cadillacjeff7777 Posted September 4, 2014 Author Report Share Posted September 4, 2014 Could a P0174 be tripped by aged plugs? I don't feel it missing. What plugs would y'all recommend? 2008 DTS Link to comment Share on other sites More sharing options...
KHE Posted September 4, 2014 Report Share Posted September 4, 2014 Could a P0174 be tripped by aged plugs? I don't feel it missing. What plugs would y'all recommend? AC Delco dual platinum plugs - same as what was installed at the factory. If you don't feel it missing, I doubt it is plugs. Does the 174 code re-set? It's possible that a sluggish oxygen sensor would cause the problem but that would set a code of it's own. Someone will post the diagnostic information for the P0174 code. Kevin '93 Fleetwood Brougham '05 Deville '04 Deville 2013 Silverado Z71 Link to comment Share on other sites More sharing options...
Texas Jim Posted September 4, 2014 Report Share Posted September 4, 2014 Could a P0174 be tripped by aged plugs? I don't feel it missing. What plugs would y'all recommend? AC Delco 41-987 Link to comment Share on other sites More sharing options...
Texas Jim Posted September 4, 2014 Report Share Posted September 4, 2014 Here is a little info on the P0174... . http://engine-codes.com/p0174_cadillac.html Link to comment Share on other sites More sharing options...
barczy01 Posted September 4, 2014 Report Share Posted September 4, 2014 Replacing the plugs couldn't hurt, service the tbody and replacing the fuel and air filter. Ideally I would like to have a scanner on the car to check the oxygen sensors activity. No timing belts on these cars and if indeed you need an oxygen sensor don't use a bosch sensor. Link to comment Share on other sites More sharing options...
cadillacjeff7777 Posted September 4, 2014 Author Report Share Posted September 4, 2014 Can the AZ scanner tell display the O2 readings? 2008 DTS Link to comment Share on other sites More sharing options...
Logan Posted September 4, 2014 Report Share Posted September 4, 2014 I think you mean serpentine belt. As for o2 sensors....AZ loves to sell those. Unlikely the problem. The fact that the intake was replaced makes that highly suspect. Maybe a pinched or folded gasket.. 174 is bank 2 lean. Bank 2 on the Northstar is the front bank of the engine (some good news..). The intake rubber plenums are known for rotting out. Typically at the bottom where intake juices collect in the rubber. I have not worked on a 2008...but looking at the service manual the 2008 does use one. See attached picture (#1 is the hose clamp used). I do not know if it is the same part as the earlier cars. Typically if the coupler goes bad you will get both a 171 AND 174. They are about $20 at Cadillac. Code scanners are pretty cheap. For $100 you can check it yourself whenever. It wont do what a Tech2 does...but can be helpful. Logan Diagnostic LLC www.airbagcrash.com www.logandieselusa.com www.ledfix.com www.ledfix.com/yukontaillightrepair.html www.ledfix.com/ledreplacements.html www.ledfix.com/j42385toolrental.html Link to comment Share on other sites More sharing options...
Eldoradoman2001 Posted September 4, 2014 Report Share Posted September 4, 2014 Don't be scared of your car ,it doesn't have pulled headbolts and blown headgaskets, it has a lot of life left in it. I've seen this year car with 200,000 miles on them and running strong ,engine quite as a mouse eating paper!!!LOL Link to comment Share on other sites More sharing options...
cadillacjeff7777 Posted September 5, 2014 Author Report Share Posted September 5, 2014 And....the CEL is on again. 2008 DTS Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.