MAF sensor problems

2000 CADILLAC ELDORADO
110,000 MILES • V8 • FWD • AUTOMATIC
Avatar
GHOSTSOLDIER
  • MEMBER
  • 6 POSTS
I recently replaced the MAF sensor on my 2000 Cadillac Eldorado ETC (Northstar V-8) because of poor performance and faulty codes, but it did not solve the problem.

Upon closer examination, I noticed that the MAF sensor harness and plug are stretched extremely tight, and I was told by a mechanic friend that a loose wire in the harness or plug could cause the code errors and cause the poor performance.

Here's my question: Can I safely rotate the MAF sensor (and seals) to relieve the tension on the plug and harness, and will it harm vehicle performance?

Thanks!
Jan 20, 2011 at 1:50 AM
Advertisement
Avatar
FACTORYJACK
  • CERTIFIED EXPERT
  • 4,159 POSTS
It the wires have been stretched, relieving the stress is only going to address the cause, and not the effect. If the wires are damaged, they would need repaired. Have you been able to view any MAF data, is it working. If there were damaged wiring it should not work at all. Often times MAF problems are caused from an underlying concern, possibly a vacuum leak. You can also identify that by checking fuel trim data. Is the P0101 the only code you have, or do you also have P0171/p0174.
Jan 22, 2011 at 6:58 AM
Avatar
GHOSTSOLDIER
  • MEMBER
  • 6 POSTS
Gstacy,
I have both codes (PO101 and PO171/174) as History; when I clear the PCM codes, and drive the car, those codes reappear. I have checked the MAF sensor seals, clamps and the intake duct (up to the TB)...could it be the seal from the plenum to the intake?
Rob
Jan 24, 2011 at 6:23 PM
Advertisement
Avatar
FACTORYJACK
  • CERTIFIED EXPERT
  • 4,159 POSTS
More than likely, that is exactly what it is. That is the reason I had asked if you had the otehr codes to accompany. That plenum boot over time, splits on the lower portion of it. If you had some other symptoms like high idle, or were able to view active fuel trim data, you could spray or use propane around that plenum and observe the change. In fact, in significance of that fault, I am currently waiting for approval to replace one on an 02 STS. If you are going to remove the intake(which you will have to to replace the plenum), I would replace the intake seals as well.
Jan 24, 2011 at 9:50 PM
Avatar
GHOSTSOLDIER
  • MEMBER
  • 6 POSTS
Thanks for the tips and reassurance, G...I'm going to order that plenum seal and the intake seal set, and install them ASAP...I'll report back here with the performance results, once I'm done!
Rob
Jan 26, 2011 at 1:50 AM
Avatar
FACTORYJACK
  • CERTIFIED EXPERT
  • 4,159 POSTS
I think you are on the right path.
Jan 27, 2011 at 3:22 AM
Avatar
GHOSTSOLDIER
  • MEMBER
  • 6 POSTS
Just an update: I bought a can of carb cleaner, aimed a couple of shots at the TB/plenum joint, and the idle picked up immediately...looks like this is definitely the culprit! I'm not happy I have to change it out, but I am happy we figured out where the problem lies!
Jan 31, 2011 at 3:30 AM
Avatar
FACTORYJACK
  • CERTIFIED EXPERT
  • 4,159 POSTS
Just be cautious of using carb cleaner. It is flammable, and the temperature for it to flash is possible.
Jan 31, 2011 at 4:31 AM
Avatar
GHOSTSOLDIER
  • MEMBER
  • 6 POSTS
Thanks for the warning...I only shot it twice, and then let it be. I have ordered the plenum seal, and will pick up the intake seals locally; if all goes well, I should be able to change it by this weekend!
Feb 1, 2011 at 9:29 PM
Avatar
GHOSTSOLDIER
  • MEMBER
  • 6 POSTS
Gstacey...I just wanted to let you know that I changed the plenum gasket last weekend, and the car runs like brand new!

Thanks so very much for all your advice, tips and help in solving this issue!
Feb 17, 2011 at 8:52 PM
Avatar
FACTORYJACK
  • CERTIFIED EXPERT
  • 4,159 POSTS
Good deal, thanks for letting me know.
Feb 18, 2011 at 3:34 AM