: 00 N* VIN Y cyl 2 and 7 misfire or spark problems

05-05-10, 10:37 PM
I am having troubles with a 2000 Deville DHS VIN Y (275hp). It started with the engine idling roughly and hesitate and act rough while driving.

I don't have a computer to diagnose and pull codes so I had the costumer go to a workshop with a computer to pull the codes.

P0386 so I replaced the crankshaft position sensor B and had the costumer return to the workshop with directions on the Variation Learn Procedure for the sensor.
The engine was better but in no way near the Cadillac standards. Still acting rough and hesitates and shakes the car a bit.

The costumer had his car once again diagnosed - the workshop not giving him the codes but told him the car needed new spark plugs.
"Cylinder 2 and 7 are not getting enough spark or it misfires" the men in the workshop said.

Fair enough - the spark plugs are replaced.

Well, once again the engine improves but once again it is not how it should run. The roughness isn't as bad as it used to be but it's still messy.

Are there any common issues that come to mind when cylinder 2 and 7 are misfiring or not getting enough spark to experienced Cadillac mechanics?
Anything I should bare in mind or look at?
The car will be connected to a computer tomorrow or the day after.
I wait for the results of the diagnosis but I also want to have tips and pointers to look at from people that know these engines and cars. The workshop that has the computer are mostly in Chevys so I just want the error codes from their computer.

Also, do you know how I can buy a computer or some equipment so I can read codes without having to spend thousands of dollars?
I lost my job so I rented a big garage, got myself a car lift and I'm doing monkey business to get by.
For some weird reason I seem to be getting N* Cadillacs.


I am not very clever in technical terms in english so I hope you as the reader may understand the description I am making, and replace misleading words with more appropriate words to make the description "make more sense."
The "roughness" and "hesitation" description is for the engine that shakes, while idle the RPM jumps up and down (just a little bit) and while driving the car sometimes shakes because of the "roughness" of the engine. As of right now I have no idea what words I should put instead of these two.


05-06-10, 08:09 AM
ice, Welcome !!!

All N* prior to 2005 (?) cars have a built-in code reader/scanner.

The car you are working on already has its own code reader/scanner/memory. Read the sticky thread at the top of this engine main page or at the top of the Deville Forums page - titled "How to pull codes". You can read codes at any time with just the key ON or with the engine running. Practice, write down the codes, noting whether each is Current or History, (as in: P0386C) then return to the sticky thread and use the URL with "obd2" in the address to get the meanings of each code: click on the blue lines in the Master Index for any P,B,C, or U codes found.

It is usually not necessary to do a CranKshaft Position sensor (CKP) relearn unless the engine develops low rpm driving problems.

Your codes say the miss is in cylinders 2 and 7. These are in opposite ends of the engine, so that is mysterious. BUT those cylinders follow in the firing order: 1-2-7-3-4-5-6-8

Rough running and missing is usually caused by either poor ignition or fuel/air mixtures. The security of the air intake duct is important - ANY air leak between the MAF (Mass AirFlow sensor) and throttlebody will cause roughness. Check the vacuum lines at the throttlebody top and sides for security. Check the PCV vacuum line from the rear cam cover to the center inside end of the intake manifold - this car does not have a 'rattle' PCV valve - it has a fixed orifice I believe. Listen to each fuel injector with either a long screwdriver held against an ear or use a stethoscope with a piece of vacuum tube attached - each injector should emit a steady "tick-tick-tick-tick" at idle. Did you check the insides of the spark plug boots for carbon tracks ?? Those boots, if dirty, will ground a plug and render it inoperable. Check/clean the electrical connector at the CMP (CaMshaft Position sensor) on the front lower face of the rear cam cover - in front of where the rear exhaust cam drive sprocket is.

You might consider a professional subscription to www.alldatadiy.com, an online service manual/recall/service bulletin database.

05-06-10, 10:29 AM
P0386 so I replaced the crankshaft position sensor B
You should replace BOTH sensors at the same time as GM had a bad supplier and almost all 2000 to early '03's will need to be replaced.

Another common problem on the 2000+ engine that Sub touched on is the plenum duct. It's the rubber coupler between the TB and the manifold. They tend to rip on the bottom causing unmetered air intake BEHIND the MAF sensor.

05-09-10, 07:01 PM
submariner and Ranger, thank you a lot for your input. You have been very helpful as always.

I finally got a change to pull the codes using the onboard computer.

B0429 - Temperature Control # 3 Rear Circuit Range/Performance <--- This one I have no idea what means. This is a head scratcher for me. What does this code mean and how do I fix it? What parts do I need?

P0300 - Engine Misfire Detected <--- You have both explaned what I need to do and check to fix this bug.

P1381 - Misfire Detected - No Communication with Brake Control Module <--- Again, a head scratcher for me. What does this mean and how do I fix this problem? Could this be the reason for the P0300 code? I will never the less also look at what submariner and Ranger have pointed out.
Although P0386 does not come up, I told the owner of the Cadillac that we needed to swap both sensors. I must admit I gave him a used sensor that I had in a engine I pulled few months ago. I told him about the bad supplier GM had from 00-03.

Any and all thoughts and pointers are welcome!

05-09-10, 10:09 PM
B0429 - Temperature Control # 3 Rear Circuit Range/Performance <--- This one I have no idea what means. This is a head scratcher for me. What does this code mean and how do I fix it? What parts do I need?
This code is referring to the rear seat temperature control actuator. It means that the actuator is not in the commanded position. I was told that it takes very little offset to set this DTC. Check to see if you are having a problem. You may not even notice it or you may not use the rear seat and can ignore it if you wish. The actuator is actually up front by the blower.

Don't know what to tell you about P1381.

What year engine did the CKP sensor come out of? If it was 2000 - 2003 and it was OEM, then it could be faulty. GM had a bad supplier. I forget what color the bad ones where, but I know Sub remembers.

05-10-10, 08:45 AM
The original 2000+ CKP's were: one black, one tan, made by Siemens in Mexico (printed on the side of the connector skirt.)

The replacements are : one black and one gray, made by DENSO in Japan.

(Looking at codes nearby P1381 it appears that the code is some sort of a data check associated with engine controls, but I'll be damned if I can figure why................)

06-02-10, 08:17 PM
Hello all once again. I finally got the CKP's and installed them. But now the engine refuses to start! (I also replaced the wheel hub on the passenger side but that's irelevent).

The codes I pulled now:
C1295 - Brake Lamp Switch Circuit Open
B0429 - Temperature Control #3 Rear Circuit Range/Performance
P0336 - Crankshaft Position (CKP) Sensor A Performance <---NEW CODE
P0341 - Camshaft Position (CMP) Sensor Performance <---NEW CODE
P0386 - Crankshaft Position (CKP) Sensor B Performance <---Now new but did not show up last time.

I ordered these from partstrain.com
http://www.partstrain.com/store/?PN=4294949374&N=0&VN=4294967189+4294966200+4294966144+4294963381+429 4966883&Nr=AND%28universal:0%29
The first two. When I ordered the ACDelco wasn't avalible but it appeares to be now.

Does anybody know what the problem could be? This wa suposed to be a simple plug-and-play job.


06-02-10, 09:42 PM
Gotta be something simple like a dirty or loose connector. I think the connectors are different so that they cannot be crossed.

06-02-10, 10:13 PM
Yes, the connectors are plug-specific. Either the CKP's themselves or the connectors are not properly installed.

That website - exactly which CKP's did you stuff in the holes ??? (OK - the first two - should be OK)

Mark C
06-03-10, 10:38 AM
Plugs on the CKPs are different, but I think you can stuff the wrong one in the wrong hole, they will just end up upside down, and may actually hit the reluctor on the crank, since the side that is supposed to face the reluctor has the notch on it

06-03-10, 04:04 PM
I swapped the CKP's again, put the old back in and the car started up.

The Codes that showed up are:

P0300 - Engine misfire
B0429 - Temperature Control #3 Rear Circuit Range/Performance

Could it be both the new sensor are broken/no good?

The ABS and Traction Control lights are off but Service Engine light is flashing.

I did a search when here when I had this code: P1381 - Misfire Detected - No Communication with Brake Control Module - and saw that people were not sure what it meant.
When I replaced the wheel hub I noticed the two wires for the ABS sensor was cut off (disconnected) and when I replaced the wheel hub this code is now history.

06-29-10, 09:32 AM
This engine is still having problems. It seems to only run on 7 cyl. Could it be the ignition coils? $720 is quite a lot to pay to check if that's the problem.
What do you guys think? Should I go for it? Where do you recommend buying it from and what brand?

06-29-10, 11:49 AM
The 2000 uses coil cassettes, not individual coils. Although one is gray, the other black, the cassettes and their ICMs are physically and electrically/electronically identical.

Look at www.rockauto.com - they were having a sale on closeout DELPHI coil cassettes - these are the OEM factory coil units.

06-29-10, 12:18 PM
These cassettes don't fail very often either so you might want to try a junk yard cassette for a LOT less money.

06-29-10, 12:33 PM
WOW! The price difference is huge! Thanks for the link. Partstrain offered them for $360 a piece! I have to look closer at RockAuto for parts.

I know these cassettes don't fail often that's why I'm wondering if I should try them out, just to see if that's the problem. The engine is still misfiring and some guy at a garage that specializes in GM cars (mostly Chevys though) told the owner it's the ignition coils (or cassettes).

But learning how to pull codes by myself on this website we saw nothing about the coil cassettes, only the CKP sensors (witch we replaced but the car wouldn't start, so we put the old ones back in and the code went History).

So I'm thinking maybe the coil cassettes can fix this issue. Or should I try something else?
There are new spark plugs and new boots.

06-29-10, 04:18 PM
You could try swapping the cassettes and see if the misfire move to different cylinders to confirm the cassette as the culprit.

06-29-10, 08:40 PM
Ranger, thanks for the advice, I didn't know I could do that until I saw the pictures from Rock Auto - I saw the possibilities to swap the cassettes, I didn't know that was possible before hand. The pictures I saw of the cassettes were taken from above. It also didn't cross my mind when I changed the spark plugs.

I guess I will become a Northstar pro after talking to you guys and working these projects. :D

06-29-10, 10:26 PM
The only difference between the two is the color. Front is silver to match the beauty cover and cam cover. Since the back one is not seen it is left black.

06-30-10, 08:59 AM
:stirpot: ........and the rear cam cover is black also.

....... remember that you can change the ICM in those coil cassettes - both ICMs are identical - same p/n. 2 screws and plastic retainer tangs.

(You will find that www.rockauto.com, www.gmpartsgiant.com, www.gmotors.com, and Luke in Parts at Lindsay Cadillac, over there >>>>, can supply you with 99% of the parts you need, quickly.) The chain stores are good for rags, hand cleaner and fart-can mufflers - for real parts use the addresses mentioned.

06-30-10, 12:32 PM
.and the rear cam cover is black also.
I never noticed.