Author Topic: Idle problems I need help!! (Read 4946 times)

nofear3544 · « **on:** January 17, 2008, 02:17:33 PM »

I have a problem with my idle. Car runs fine but when I stop at a light or stop sign the idle never falls down to the same spot and sometimes it will even stall out. After I stop it will fluctuate usually anywhere below 1200 rpms. I had my mechanic replace all hoses he thought were necessary along with the boot and I tried replacing the ICV. Neither helped so I thought it could be a bad AFM so I borrowed one from another car and since I replaced the AFM the car hasn't stalled but still has a bad idle (fluctuates b/t 600 and 1100). Is there anything else I should look for or are these the main idle problems. There is no check engine light and Ive looked over the hoses many times and can't seem to figure this one out.

sumyungguy · « **Reply #1 on:** January 17, 2008, 03:28:07 PM »

same problem here..

kowalski · « **Reply #2 on:** January 17, 2008, 05:30:21 PM »

did you replace it with another used AFM?

hoevesruperd · « **Reply #3 on:** January 17, 2008, 07:19:26 PM »

check your vaccum hoses, not only the ICV gets carbonated

haledj · « **Reply #4 on:** January 17, 2008, 08:48:36 PM »

A steady idle is for the weak.

just kidding, good luck

RED IS 91 · « **Reply #5 on:** January 17, 2008, 08:57:28 PM »

you've got to check those hoses !!!!

http://www.esatclear.ie/~bpurcell/318isfaults.html#inletmanifoldleaks

nofear3544 · « **Reply #6 on:** January 17, 2008, 09:29:16 PM »

do i need to pull the manifold? also I just got the brilliant idea to check my car for codes and it came back 1222 which is the o2 sensor. I have one hear that I think Im going to try and replace and see if that works. Its snowing/raining now hopefully it will be alright to work on it tomorrow.

RED IS 91 · « **Reply #7 on:** January 18, 2008, 08:07:24 AM »

If your going to check and replace the hoses under the manifold then you'll have to remove the upper manifold. Change out the o2 sensor and see if that makes a difference .

nofear3544 · « **Reply #8 on:** January 18, 2008, 11:25:39 AM »

okay so it turns out that this o2 sensor is a pain and wont come out. to make it worse i totally destroyed the old sensor but its still stuck in their. Its partly stripped because ive basically tried every way to remove it. So i went out and bought the right tool you know the o2 socket and it turns out the socket is too big for the space that im working in and i cant get the socket over the sensor. Im really getting a headache from this job.

Wise Old Dog · « **Reply #9 on:** January 18, 2008, 02:41:23 PM »

The O2 should always be removed while hot. The hotter the better. Put a torch on it.

RED IS 91 · « **Reply #10 on:** January 18, 2008, 04:04:53 PM »

put a torch or heat to it and clamp some vise grips on it.
When I did mine I soaked it with pb blaster and waited 15 minutes and it came right off.Yours is probably the original. How many miles on your car ?
good luck

kowalski · « **Reply #11 on:** January 18, 2008, 08:31:10 PM »

Quote from: RED IS 91;41391

put a torch or heat to it and clamp some vise grips on it.

+1 the torch is a good idea. if you've got a welder just get a metal bar and weld it to the 02 sensor.

nofear3544 · « **Reply #12 on:** January 19, 2008, 12:33:10 PM »

yea thats what happened I needed heat my uncle came over with his torch and it worked even thought the threads were ruined. I took it over to minake to have it re welded and threaded. theres are 159k on the car and Im not sure if it was ever changed. I did put 40k on the car since I owned it so who knows how longs its been on their for. I just plugged it in and it seems to have helped, wont know till i really drive it. Thanks for all the input ill keep everyone posted.

nofear3544 · « **Reply #13 on:** January 24, 2008, 10:46:28 AM »

Okay.. so things are better but not great. Car hasn't stalled but its still idling rough and it feels like when i give it gas there is a slight hesitation in 2nd gear. Also I took the car through inspection and it failed for HC (hydrocarbons). Does anyone know if this a fix I can do by myself or does it need to go to the mechanic. This may have something to do with my idle problem.

Scany · « **Reply #14 on:** January 24, 2008, 11:15:01 AM »

Have you checked your cat? If it's clogged you might loose power. i was thinking since you failed inspection. Also I'd check the throttle body to see if the valves are opening correctly when you give it throttle. You might have a leak there too.

We took the whole intake off and replaced most of the hoses and cleaned out the intake manifold and stuff. Still idles a little rough, but nothing serious. We haven't replaced O2 sensor yet (heat and a 22mm wrench does the work for me with O2 sensors). Realoem.com is great for seeing how all the hoses and stuff is put together.

Since the Bentley manual doesn't cover the M42, does anyone know where to find DIY writeups for this engine?