My 1994 seville hesitates/ runs rough but only at 1300-1600 rpm, any gear.
the only code set is p106, (map sensor). I know that doesn't necessairily mean the map sensor is bad. Anyone else seen this problem?
It runs great at all other rpm ranges.

My 1994 seville hesitates/ runs rough but only at 1300-1600 rpm, any gear.
the only code set is p106, (map sensor). I know that doesn't necessairily mean the map sensor is bad. Anyone else seen this problem?
It runs great at all other rpm ranges.

P106 is 'stop lamp switch input circuit problem'. Are you sur yo dont have a PO71 or PO109? What kind of manual are you using?

Logan

P106 is 'stop lamp switch input circuit problem'. Are you sur yo dont have a PO71 or PO109? What kind of manual are you using?

Logan


Love that spell check option....'sure' is one..the other is 'you'

I don't have the manual, got the codes off the net. P106 is the only code that comes up, and only after I run it in the 1300-1600 rpm range for an extended period.

P106 is 'stop lamp switch input circuit problem'. Are you sur yo dont have a PO71 or PO109? What kind of manual are you using?

Logan

Logan is right, Your DTC is a stop lamp input circuit problem. The P106 that you found online that said it was a MAP sensor circuit problem is for OBDII compliant cars, (1996 and Newer) Some cars built before 1996 were OBDII compliant but I am not sure what models, but according to my resources Cadillac was not until 1996. So your '94 is more than likely OBD1. OBD1 and OBD2 use many of the same trouble codes but do not have the same meaning. For example your P106 code diagnoses 2 totally different faults depending on what year model the code was retrieved from. Hope this helps...

OK, I think you guys are right in the stop lamp switch circuit p106 code. (I'm trying to get the correct manual for this car, I have book 2).
Now if driven steadily in 1300-1600 rpm range, the traction control disabled message comes on and code T067 (I think), sets,(a tcs code).
There is a horrible vibration at this rpm range. As I said before, this only occurs at 1300-1600 rpm. I have not inspected the under carriage yet, as I just bought it a week ago. This problem did not occur on the test drive of course. I used to work at a Cad dealer (ABS and handling), and never saw this problem before. I have seen bad inner axle joints cause severe vibration, but this seems different. Any help appreciated.


Logan is right, Your DTC is a stop lamp input circuit problem. The P106 that you found online that said it was a MAP sensor circuit problem is for OBDII compliant cars, (1996 and Newer) Some cars built before 1996 were OBDII compliant but I am not sure what models, but according to my resources Cadillac was not until 1996. So your '94 is more than likely OBD1. OBD1 and OBD2 use many of the same trouble codes but do not have the same meaning. For example your P106 code diagnoses 2 totally different faults depending on what year model the code was retrieved from. Hope this helps...

Traction Control CodeT067 is a Brake Light Switch Fault. So both of your trouble codes are Brake related, but I have no idea why it would only vibrate and set the codes at 1300-1600 RPM, and not all the time. The vibration / hesitation and the codes that are being set may not even be directly related...Maybe whatever is causing the car to vibrate is not setting a trouble code, but the vibration is causing a bad/loose connection in the brake and traction control systems and that is where the codes are coming from.

Thats what I'm starting to think also. Further diagnosis this weekend.

Traction Control CodeT067 is a Brake Light Switch Fault. So both of your trouble codes are Brake related, but I have no idea why it would only vibrate and set the codes at 1300-1600 RPM, and not all the time. The vibration / hesitation and the codes that are being set may not even be directly related...Maybe whatever is causing the car to vibrate is not setting a trouble code, but the vibration is causing a bad/loose connection in the brake and traction control systems and that is where the codes are coming from.

Although it feels like a bad inner axle joint at times, it may just be a fuel delivery problem.
A new code set on saturday ,P046 (Right to Left Bank Fueling Difference). The previous owner said it just had a 100k service and the spark plugs appear new(ngk), but I don't know if the fuel filter was changed during the 100k service, I'll check it out today.
It is also possible that the fuel pump is starting to fail.
(I also installed new spark plug wires as the old ones appeared original.
That improved overall smoothness, but vibration still there @ 1300-1600)



Thats what I'm starting to think also. Further diagnosis this weekend.

Update:
For all who wish to save time and money.
This problem was caused by clogged egr ports under the intake manifold.
I removed the intake and scraped all the carbon off the egr passages, reassembled engine, and roadtested. Hesitation/vibration gone.
I'm sure this may be covered in other posts on this forum, but I didn't think it was applicable to this situation. Dealer wants over $400 to do this job but I did it in about 2.5 hours. It was well worth it. If you suspect this is your problem, unplug the egr valve and road test. If hesitation is gone, you have clogged egr ports.
Hope this helps someone.


Although it feels like a bad inner axle joint at times, it may just be a fuel delivery problem.
A new code set on saturday ,P046 (Right to Left Bank Fueling Difference). The previous owner said it just had a 100k service and the spark plugs appear new(ngk), but I don't know if the fuel filter was changed during the 100k service, I'll check it out today.
It is also possible that the fuel pump is starting to fail.
(I also installed new spark plug wires as the old ones appeared original.
That improved overall smoothness, but vibration still there @ 1300-1600)

I don't have the manual, got the codes off the net. P106 is the only code that comes up, and only after I run it in the 1300-1600 rpm range for an extended period.
Where did you find those codes at on the net? I found a site that shows some codes but i too recieved the code P109 and have yet to find a place that tells me what that code means..They only go up to 99 and anything over 100( in the code that is) is not available..BTW i have a 1993 Cadillac Eldorado