- 05-20-14 02:39 AM #1Cadillac Owners Member
- Automobile(s): 2008 Cadillac DTS, 1986 and 1970 Fleetwood 75 series Limos
- Join Date
- Sep 2013
- Buffalo/Western New York
2008 DTS disappearing lights/messages, seeking advice!
Been lurking in the background for a while here and love the wealth of knowledge and dedication I've seen among the forum members! I've found myself in the middle of some issues I'm having with my 2008 DTS, wondering if anyone else has had these experiences, as I'm worried that our dealership may be pulling the old "throw parts at the car and hope something sticks" trick on me. Here's an outline of what's been going on-
The main issue that brought me to the shop began this past Friday evening. I had run to the grocery store and upon leaving I got the DIC message "Oil pressure low- stop engine" with chimes and a flashing oil light. I pulled the car back into a parking spot at the store, checked my oil, it looked a bit low so I ran into the store and bought two quarts of oil. Added them and started the engine, no light, message or chime, until I started pulling away again. I was unsure of what was going on, but it being late and not too far from home, I decided to drive the car home being sure to listen for out of the ordinary sounds from the engine and watching my gauges closely. The next morning I was first in line at our local dealership in a small town to have the car looked at. It gave me the same light/message/chime routine on my way down to the dealer, which I explained to them what had gone on (plus I needed an AC recharge, and I explained another issue I had noticed over the past couple weeks, more on that in a moment).
The other issue I brought up to the mechanic was the following recurrence of lights and chimes: sometimes mostly on acceleration up hills the check engine light would flash, traction light would come on, chime would sound and the engine did feel/sound to me as if it weren't firing right/a bit shaky and unsure feeling would be the only way I could describe it. The first time this happened I pulled over and shut the engine off as per the owners manual, waited the suggested time, restarted and had no problem. It's since happened several times, always resolving itself once I've gotten to the top of the incline. I don't think the oil light issue and the CEL issue are necessarily related, but this leads me to the direction the dealer wants to go in.
They waited until Monday afternoon to look at the car, and didn't get an oil pressure warning, the CEL came on solid and they pulled the code- PO411 secondary air injection system incorrect flow detected. They kind of acted like I made the oil thing up, which I assure you I did not! And they said to replace an "air sensor" was going to be around $600. I regrettably do not have a copy of the paperwork in front of me, only a couple photos of the paperwork that I took while speaking with the dealer today when I went to pick up the car. The part has been ordered and I am going to be bringing it back in when they have time to do the work and I can wait for it to be done (otherwise I think they might keep it for another several days while they find time, and I can't be without a car for a long time), but I'm curious as to whether they're trying to charge more for the work or part than they rightfully should be, I feel they have tried giving me special "Cadillac pricing" on repairs in the past and I've been successful in bringing them down to earth...
They said there was no record of any oil pressure events in the computer, suggested that it may be a computer/electrical problem, and told me the car should be fine to drive after i showed concern about driving it and possibly causing further damage. Again I felt like they thought I was crazy for being concerned. This car is my baby, I have only had it since September 2013, and I have put almost 20,000 miles on it since I got it, I spend a lot of time in the car and even more so now that I have a car I actually love to drive once again! I'm at just over 94,000mi on the odometer and haven't had too many problems with the car in the time I've owned it, this is really the first serious issue I have come across. I just thought I would post what I experienced and what they are telling me and see if anyone has advice, warnings, reassurances, or guidance for me. I'm no mechanic but I'm not an ignorant person either, I try to learn all I can in these kinds of scenarios. I will do my best to answer questions to help figure out what's going on. Would love to hear from anyone who may have had similar issues and how you resolved them. I don't want to get caught in the endless cycle of replacing parts without knowing the problems, and I worry that our dealership has no problem not only fixing what's not broken but also charging us special cadillac prices. I've reminded them just like I've had to remind folks at the church I work for (as organist/choir director) that they sell Cadillacs USED as well as new, and no, the organist isn't making enough money to buy a brand new $60,000 car...
- 05-20-14 02:13 PM #2
Re: 2008 DTS disappearing lights/messages, seeking advice!
Here is something you might want to try... just in case some of the computers are having a glitch...
There is a way to REBOOT all of the electronic modules in the entire car.
Sometimes (lots of times) that will fix random electrical gremlins.
Remove BOTH battery cables... negative cable FIRST...
Touch both cables together for 5 seconds or so, making sure they have good contact with each other.
This will drain all the capacitors in the system.
While you have the cables off... undo the one bolted to the floor.
Take a little piece of sandpaper and sand the paint away from the attachment point.
It will then have a better ground.
Re-attach the battery cables... negative cable LAST...
You will have to do the window EXPRESS UP learn again and you MAY have to do the memory seat settings again.
Sometimes they will forget the seat settings and sometimes they don't.
- 05-20-14 02:55 PM #3
Thank you, I will try this today or tomorrow. A user sent me some applicable service bulletins as well that provided some great info!
- 05-21-14 12:35 PM #4
Is not a cheap fit I had the same problem with a 06 dts that I used to own if your are able to look at my post the infor is there. Do nit spend money on computer and on any thing that your mechanic will tell you here is the bad new p0411 is not enough freash air reaching the bank one oxygen sensor. What it is a clog valve head the one against the fire wall. You do not have to remove it a good mechanic would do it first remove exhaust manifold from the bottom of the car when you see yhe head by rhe exhaust come out there 6 pin side hole that get clog clean them with cab cleaner. That would fit the problem. Good lk
Do not keep changing part and those sensor are going for 150 in th the Internet if you have mechanical sense it is a do it you self. Not 600 these mechanic think that because we drive cadi they could take money alway from us.
these one of post from last year before and around march
grullon10 is online now
Cadillac Owners Fanatic
Automobile(s): 2006 cadillac dts
Join Dateec 2012Age:43Posts:242
Finally fits the problem is the small holes on the head by the exhaust manifold they get totaly clog get get clean you have to remove the exhaust. Loose the rack and when you get to the head clead those holes with a small drill tip or small flat head screwdriver my was so bad that we could not get the screw driver in with a lot of work we got it clean it working find now.
you may also have a bad oil pressure switch that is very cheap by the oem the other ones go bad very fast.
- 05-21-14 05:33 PM #5Originally Posted by grullon10
I'm in my 20s, and I won't lie, I often need some help from my folks when it comes to car repairs that come out of the blue. The downside is I don't always have a lot of say as far as where I take the car for work to be done and what gets done. This part has been ordered and I'm taking the car in tomorrow afternoon to have it installed. They are also going to check what's going on as far as the misfiring (now that they believe me when I said it was happening. I may be young but I'm not the type who puts all my stock in technology to solve problems, but I can understand that they'll be more likely to believe what the computer says over what the driver/owner says). I'm hoping it's just time for spark plugs or something, we will see what they say tomorrow.
As far as the oil pressure light/chime/message, it still hasn't happened again, so I don't know what that's all about. If it's a cheap part it probably wouldn't hurt to replace the pressure switch, but i would think that if that had caused the problem then it would happen again. Some friends thought maybe it needed to be reset after adding oil (like how you often need to drive X amount of miles to "reset" the engine light) but with such an urgent message you'd think that wouldn't be the case with the oil light. If the car tells you to "stop engine" how can you in good faith drive it 50 miles to reset the system? I don't know, it just seems like common sense to me. Hopefully things will be more or less resolved without any further intensive repairs. I really love this car, I have always loved Cadillacs and get so much pleasure out of owning a car I enjoy looking at and driving daily. Thanks to everyone for their help and ideas, I'll report back tomorrow when I get some more info. I guess I have inherent distrust for the dealerships around me. There are two Cadillac dealers (well, GM dealers that include Cadillac in their lineup) within a logical distance of home. The first one is where I bought the car used last fall. They were great until the final stages of the sale, throwing paperwork at me to sign without saying what anything was and not giving the opportunity to read things over, they took several days to fix a problem with the brakes that I noticed during my test drive and even then they replaced the rear brakes when I KNEW the issue was in the front. That dealer changed hands not a month after I bought the car, and I haven't been back in to check them out since. The dealer I've been taking the car to for service is a small town dealership which is very close to home but they have to really be watched and haggled with to avoid paying "cadillac tax" on repairs. Still, I can't complain too much, this car has been far more reliable than the Saturn Aura it replaced and far cheaper to maintain than the Lincoln Continentals I owned before that!
- 06-04-14 12:20 AM #6Cadillac Owners Fanatic
- Automobile(s): 07 dts 1986 fleetwood brougham d'elegance
- Join Date
- Jun 2011
- BROCKTON MA
Re: 2008 DTS disappearing lights/messages, seeking advice!
any more info on the oil light message coming up??????
- 06-04-14 12:53 PM #7
Re: 2008 DTS disappearing lights/messages, seeking advice!
Intermittent "Oil Pressure Low - shut off engine" warning.
This is an easy fix. I've done on my '02 Deville, my '06 DTS, and a friend's '07 DTS.
The engine's oil pump is very basic and would be very surprising to hear of it failing. If it did, you wouldn't make it home from anywhere without the engine seizing.
It's the sending unit or the wiring. Most likely it's the sending unit. I ordered AC Delco replacement's for under $15 with shipping from Rockauto.com
It threads into the oil filter adapter. Some people take the adapter off of the engine to swap this part which would require you to get a new gasket but it is very doable without taking anything off.
Secondary Air Injection code has come up on my '02 Deville, both my '06 DTSs, and my '09 DTS.
I learned the hard way when the dealer replaced the first one on my '06 DTS and it cost about $600.
It sits between the cowl and the engine right in the middle of the engine bay.
It'll run you about $160 shipped from Rockauto.com
Easy to do the job yourself if you are mechanically inclined, there are like 3 10mm bolts and 2 10mm nuts along with an electrical connection to replace.
If that was the problem it would be more prevalent when the car was idling, just after start up. The code could get tripped but more than likely it's another problem that is causing the secondary air injection flow to fall out of range. So many times, replacing that part isn't necessary. (Also learned the hard way.)
The dealer that actually fixed my problem had the mechanic, with my permission, keep the car a few days and drove it around with diagnostic equipment hooked up until the problem presented itself. Turned out to be a bad MAP sensor. $50 part and $550 in diagnostic and labor charges. Again, the CEL code stated secondary air injection valve but after the MAP was replaced, the secondary air injection code went away and never returned. There was no code tripped for bad MAP.
Other fixes could include replacing the 02 sensors or the MAF.
It's a gamble when you're changing sensors without actually knowing, but for what the dealer charges, I think it's worth the try.
- 06-04-14 05:49 PM #8
Thanks for the info! I haven't had any issues since the day I got the car back from the dealer and I had the misfire/light/message/chime happen right after startup that day. Happened once and hasn't happened again. I'm crossing my fingers that things are okay and I won't have any more issues for a while but if it starts happening again I will definitely be doing some of this myself. I could replace everything it COULD be myself for what the dealer charges for one part alone!
Now the only issue I'm having is my AC is out, after a charge it worked great for a few days then back to blowing warm air :/ of course that's a whole separate issue!
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