: 2001 Deville Stalls/rough idle

07-24-10, 04:50 PM

This is my first time here, I discovered this site while looking for reasons for my problem. I have a 2001 cadillac deville, it has 82k miles, however for the past few weeks I have been experiencing a very rough idle, I though that it may be a dirty fuel line so i ran some cleaner through, no help. and then a few days ago it stalled out on me when i was coming to a stop. I took it into my mechanic, and he said that it may be cam shaft sensors, but he wasnt sure. He did however mention that the rough idle may be part of a vacuum problem. I have read on here about the vacuum prendulm but I wanted some help on how to locate it, pictures would be great....lol. Also i read on a few sites that the stalling may be due to a recalled sensor in the transmission, but if not that any advice as to what to do?

07-24-10, 05:16 PM
Look at these and then remove the engine beauty cover. Let it idle. Shoot a shot of Brakleen or starting fluid down at the base of the throttlebody-to-intake manifold plenum clamp screw. Any idle change is a split plenum - common. Dealer only, about $35 -40. 2 hours with simple tools and a bit of gearhead experience. Look down in Cadillac Technical tips - go through a few thread pages - there's a TON of info in those 10 pages..............

BUT, if you find/decide to do the plenum job, come back here first: there are a few hoops to jump through.

(Go up to the top of the main Deville threads page and read the ENTIRE sticky thread titled "How to pull codes". It's all built into your car; you don't need a scanner.)

Click the thumbnails to enlarge............


07-24-10, 07:31 PM
Ok grabbed codes, couldnt check the engine, its a downpour here, I got as follows
IPC u1301
IPC U1016
PCM P0101
PCM P0121
PCM P0300
RCC U1000

I checked on a website linked from a article here, and I gather that there is a emmisions and powertrain issue per the codes, Does anyone know if this relates to a stalling issue? Thanks a ton

07-24-10, 09:29 PM
P0101 - Mass Air Flow (MAF) Sensor Performance

I would suspect this is your problem.

Have the CKP sensors ever been changed or are they original?

07-24-10, 09:50 PM
Either the MAF ducting is leaking air or the sensor itself is really filthy (uncommon). ANY air leak between the air filter box and the throttlebody duct clamp will cause problems in a divorced MAF installation. Also check the 5-pin connector for cleanliness and integrity.

The P0121 - Throttle Position Sensor circuit performance - check the integrity and cleanliness of the TPS connector - throttlebody butterfly valve extension.

07-24-10, 11:17 PM
P0101 - Mass Air Flow (MAF) Sensor Performance

I would suspect this is your problem.

Have the CKP sensors ever been changed or are they original?

all original

07-25-10, 12:50 PM
GM had a bad supplier for the CKP sensors (Made in Mexico) from 2000 - early '03. When they fail, you get stalls. The new supplier was Denso (Made in Japan). That may well be your stalling problem. They SHOULD set a DTC, but do not always do so. If they are original, I'd just replace them. You're gonna have to sooner or later anyway.

10-17-10, 03:20 AM
Hey guys I know is been a while, I got the plenum replaced and it started stalling alot so I replaced two of the crank shaft sensors that went bad, that was a few days ago and now the check engine light is back, but there is no problem that I can feel. I grabbed the current codes,
IRC V1016
PCM P0410
PCM P0741

I reset them so the check engine light isnt on now, and Im gonna keep an eye on it in case it was some air that got into the engine when the work was done. But any insight just in case would be appreciated.

10-17-10, 08:05 AM
The P0410 refers to the secondary AIR system - that compressor and piping system which sends fresh air to the exhaust manifolds on cold start in order to quickly light off the cat, reducing emissions.

The P0741 refers to the TCC - Torque Converter Clutch - being stuck off. That function removes the last 300 rpm of engine/transmission slip in 4th gear. It is NOT overdrive - it is converter lockup. A $50 solenoid buried $2,000 (labor) in the transmission. Do some searching - you can test the function yourself on a flat road.

Both these codes will set the SES light and both will cause the car to fail emissions testing.

01-18-11, 03:18 PM
I have similar problem with 2002 Eldorado right now. Intermittent miss code 300 and P0121 . We did have 0101 but just replaced the MAF sensor and that code is now gone. Still in a quandary as to what to do next. The idle speed and roughness comes and goes and runs up to about 1500 rpm and idles back down to about 600 where it almost stalls. I can tell PCM is trying to compensate for something that it doesn't like but what I cannot tell. HELP !

01-18-11, 03:46 PM
Check for a ripped plenum. See post #2.

01-18-11, 05:37 PM
Do that ^^^ and have you ever cleaned the IAC and throttlebody? Maybe even clean the EGR pintle and bore. Look at the EVAP solenoid and vacuum line in the rear side of the throttlebody.