Check engine light

Hello,

You must have had a glitch in the system to cause the light here is a video that shows how to clear the codes.

https://youtu.be/ahK_eucFi-k

Please let us know if you need anything else to get the problem fixed.

I'm having a check engine light which is reading as a P0430 code Catalyst efficiency below threshold bank 2... I have a 2005 Cadillac CTS with about 126,000 miles. Does my catalytic converter need to be replaced or would it be an O2 sensor on bank 2 as specified in the check engine scan?

I need to know what size engine you have?

That code is nearly always a bad converter. There are other possibilities but they are very rare. In order to set that code the front and rear 0/2s have to mirror each other for a specific period of time among other criteria it has to meet also.

Thanks, the engine is 3.6L. So, if I replace the catalytic converter should I replace the sensors also?

I bought this car last year, from Texas. I drove it back home to
Utah. The Check engine light came on a couple of days after I got
It home. I had it checked at auto zone and the trouble shooting
Code is P0496. I was wondering if is the evap sensor, because
Gm said they would replace the evap sensor for free if it had less
Than 120000 miles. It also makes a emission smell that is sucked
Into the car when the heater is running and you can smell it from the
Drivers side motor under the wheel well. Could all this be related.
And could changing the evap sensor fix the check engine light and the
Smell thanks so much.

Wrenchtech is right most of the ime it's a bad cat.Read step 3 i posted if everything checks out there then your next step is to replace the cat.I wouldn't replace the sensors they would both have to go bad at the same time to set that code.Let us know what you find and how it goes.

Possible causes

- Faulty EVAP Canister Vent Valve
- Faulty EVAP Canister Purge valve
- Plugged EVAP canister condition
- Faulty EVAP Pressure Sensor
- EVAP Canister Vent Valve harness is open or shorted
- EVAP Canister Vent Valve circuit poor electrical connection

Go get it changed for free.

Even if both 0/2s were bad, I believe you would get different codes than a PO430.

tech got 3 code off engine light.

1 loss communication with engine modeule. S00

2. high purge flow emission $00

3.class 2 data link high ABS $28

what does it all mean?

well you shold have sent the codes first not the diagnosis. it means that y ou culd have left your gas cap not tightened after getting gas, or your purge vavle may be messed up and needs to be fixed or a short in wire. The abs cold mean a wire broken someplacce andthe loss of communication can be abad battery/ground or a bad wire at the aldl or it wasn't hooked up reigh tto begin with.

I've been told multiple locations, from under the hood, to inside the gas tank ( that one makes me scratch my head ! )

it's connected to the gastank on the right rearinner fender well. you can't see it unless you look under and then maybe not even then.it's connected to a rectangular box like thing.

Thank you So much for your reply, and pretty quick, too !
Found a mechanic who will repalce it for $150.00
The dealership wanted close to 300 !
Wanted to try it myself, but it's not my car, it's my girlfriends, and if I screwed it up, i'd NEVER hear the end of it, lol !

i hear ya

Radio has been replaced but still only picks up AM, most of the time, FM normally doesn't work but comes and goes, changed o2 sensors and now they say problem is computer. 14.8 volts on display charging, then drops to 13.8, but with car off battery has only 11 volts.

Must drive everyday or batter won't start car. Battery has also been replaced.

Terrible service at cadillac so took to GM. No one has shown any knowledge of car.

Now sits in driveway and wife is bitching. Please Help!

Your O2 sensors are a separate issue from your radio and bat problem.

Your O2 sensors are controlled by the PCM, which is your power train computer. (engine/trans) The radio and other electrical accessories are controlled by the BCM, which is your Body Control Module.

You said you replaced the O2 sensors, but are you getting another code??? When the engine sets a code for these sensors, it IS NOT saying the sensors are bad. It's only pointing you in the direction of a problem. Such as the wiring/connectors/sensors. And also, your engine could be running a lean/rich condition that is causing the sensors to read something abnormally high/low, which your computer can't compensate for. Sometimes the computer will think there's a problem with the sensor or its circuit.

The proper thing to do when getting these codes is to thoroughly troubleshoot that particular system until the component at fault is found. If a mechanic just goes in to replace parts, you need to find another mechanic, one that knows what he/she is doing.

Your radio sounds as if the power antenna isn't connected properly or has a problem in the wiring. (FM stations need the antenna, AM stations don't) That's why the AM stations are coming in.

Your digital display should fluctuate from anywhere between 13-15 volts (While engine is running). That's normal. But when you engine is off, the bat should read 12.6 (at least)

If you've recently replaced the bat and it's already reading 11 volts, then there's a constant current draw on the bat that isn't shutting off when you turn the car off.

Check to make sure you turn everything off when leaving your vehicle. If the current draw doesn't disappear, then you'll need to have your fuse box probed for the current draw. And if you're unable to locate it this way, have your BCM checked out. These things often go bad and will cause all sorts of electrical gremlins to appear.

Hey i just recently got an 03 cadillac cts only had it for a little over a month. I get in my car one morning and it would not start it would just turn no crank up or anything radio worked but the car would not start. It's been three days and the cadillac dealership just told me the computer was bad so my car would not start. My warranty is over only had one month warranty with the place i got it from, but luckily with this problem it is covered by the factory warranty you should try that

how do you turn off the malfunction indicator lamp on a 2003 Cadillac cts

if you are referring to check engine light then it requires a diagnostic scan tool to retrieve and then delete the codes out of system.

What does it mean when the engine light on a Cadillac CTS 3.6 blinks 5 times?

https://www.2carpros.com/articles/service-engine-soon-or-check-engine-light-on-or-flashing

Have the computer scanned for code/s-you have a problem within the engine management system that caused the CEL to turn on-This is your starting point of diagnosis,finding out what's going on.

Engine Mechanical problem
2005 Cadillac CTS 6 cyl Automatic 69000 miles

what does 6 cyl not running means?and is it exp to repair

I need more information to answer you question.

When you turn the key, does the engine turn over but not start??? Or does it not turn over at all???

How much it cost will depend on what's wrong with it.

Had a very slight miss when under moderate acceleration. Ran a scanner and came up with cyl 3 misfire. I replace all the plugs put the car back together, hit the key and the car ran like crap. Would barely run. Also heard something "rattling". I hit the gas and it sounded like a nut or something may have fell into intake but I did not ccompletely take the intake off. I only moved it to the left and right as I needed. Also I did not end up missing any bolts or anything so I do not believe anything fell into my motor. Anyway I tore the car apart 3 more times taking every plug out and finally the knocking stopped. The car how ever is still running aweful. I have 2 coils on order right now hoping it may fix the problem but I'm not so sure. The knocking/rattling sound has me scared because I've heard horror stories about timing problems. I haven't ran my car low on oil. Check it pretty often. Also I don't understand how it could run fine then with new plugs it runs like crap. Also the first time I tore it back down after the miss started I put old plugs back in it still missed something aweful. Please any advice would be amazing. Thanks - Brandon

you may have damaged the coil to plug connector but for a misfire have apro look into it because it can be a sensor screwing up alongwith an injector and many other problems. these are very hard to diagnose why they have a misfire.

Thank you for the reply. I took the car to my local auto parts store and had it scanned again after unplugging the battery all night. 16 codes!!! The guy said that the computer has to "relearn" or something and he unplugged it before I could write them down. I guess he was in a hurry. I did see the random misfire code along with every cylinder misfiring this time. I did absolutely nothing but put plugs in. I cannot believe the car of my dreams is cropping out on me. I owe about double what it Is worth too. Is there a chance something really bad has happened? I'm calling the car lot where I got it in the morning since the nearest dealership is 50+ miles away. Any thing that you can think of that I should tell them to look at? I'm 99 percent sure I did nothing that could lead to it jumping time or nothing like that... like I said I check my oil pretty much once a week. All I did was drive home from work which is right at 50 miles and pull into the garage. No noises before changing them. Put it together and cranked her up and bam... I don't understand how I could go from 2 codes to 16 just by unplugging the battery.

1. don't believe an autoparts guy and then take to any garage they can do just as good a job as dealers. check your battery for condition including load test autoparts cando for free make sure terminals are clean a weak battery can cause a lot of problem but not he one you are experiencing.

Yea I didn't really think he knew much. I will get it scanned again this evening to see what codes come up and I will post them all. I hope it's not a timing issue. What codes would show if it was something to do with the valves or timing? Also I'm not the original owner. Is there any tsb or recalls my car may qualify for? Is not under warranty either.

there are no codes for valve or timing unless you have low compression which wold give you the misfire code. the only tsb on your car for a misfire code is an aftermarket installed alarm system that will destroy your converter and cause misfires because it'snot circuit borad driven and shuts the fuel on and off and shold be put to starting system.. as far as timing the belt shold be replaced as a kit at 60k unless in California then 105k. normally akit is used so water pump pulleys, tensioner all get replaced at same time. this is an interference engine so if the belt breaks or slips your valves bend.they also have aproblem with crank sensors which are in the timing cover so if they aren't plugged in right they screw up but I don't think that is your problem.

Ok. By what I'm telling you what would you guess is wrong? The whole thing about changing plugs leading to this has me pretty angry with it. Is there a way for someone to check and see if anything is up with the valves?

a compression test. I really thing tht the coil to plug bootsare probably screwed up causing a lot of this but hey ya never know til its 'scanned.

Ok didn't do the compression test because I really don't think it's an internal problem. I went ahead and bought some double platinum autolite plugs and installed those and it still didn't help. Hooked it up to scan for codes and it came up as random misfire and no. 1 2 and 3 cylinders are misfiring. Brand new plugs. They have 10 miles on them now. I gapped them to .050 because that is what the guy told me to do. I'm lost. Taking to the car lot I hot it from to let them check it out. Any info you guys could give me sound be appreciated. The auto parts guy said it could be where I unhooked the battery and it could possibly be a cam or crank sensor. I have no knowledge about these engines other than what I've read over the last 2 months. Thanks again!!! And we're you recommending that I should do the compression test? Or did you mean that it would tell me if my valves were bent?

if the valves are bent a compression test will show it.

My cts check engine light came on and it was placed on a computer and scan and I was told that there was no codes.then it was good for a few days and it came on again,then a few days later it cut off again and it's been doing ever since, can you guys help?

there is a code. you need a shop with a scan tool to pull the code for you.

Roy

I got two codes p0420 &p0430 let me know what you think.

Am still waiting on an answer please.

When I fill my car with gas the DIC displays the estimated amount of miles that it can have with the gas was put in, but for some reason the miles range changes significantly lower with only the passing of a few miles. i.e. the DIC would read 186 miles range, then after driving for about 3 to 4 miles it would read 96 miles range. Why would this be? I've recently had the ECM re-programmed by the dealer but I have had a check engine light reading that shows the catalytic converter being faulty and I also have custom wheels if that would make any difference....

This will be still a problem with the ECM, i would take it back and explain the problem, they may be able to do a re flash to fix the problem.