Username or Email Address
Do you already have an account?
Forgot your password?
  • Log in or Sign up

    VWVortex


    Page 1 of 4 1234 LastLast
    Results 1 to 25 of 92

    Thread: cold start / rough idle / misfire

    1. Member
      Join Date
      Feb 11th, 2003
      Location
      Winchester, VA
      Posts
      9,236
      Vehicles
      964
      12-03-2007 09:16 AM #1
      I searched through a lot of posts on this topic. Almost everyone is describing an idle that hunts around and won't settle at the proper RPM.
      My problem is different. On some cold mornings, the car won't stay running at all without me giving it gas, and runs REALLY rough like it is only firing on two or three cylinders. It smooths out in less than a minute, but I have to rev it up and down several times to get the cylinders firing, if that makes any sense. It has a new T-belt, cap, rotor, plugs, and wires as of Spring time, and was running perfect all summer.
      Could the camshaft position sensor be causing this? Coil? Right now I am getting codes for the CPS, the MAF, and the 02 pre-cat sensor, kind of a chicken-and-egg scenario.
      Running update of parts that are new or recently changed, as of 02/3/08:
      Plugs, wires, cap, rotor from GAP in spring '07
      T-belt, tensioner, thermostat from GAP, spring '07
      PCV pipe
      cleaned PCV valve, replaced breather pipe
      battery
      catalytic converter
      MAF sensor
      coil
      O2 sensor
      MAF sensor again
      two tiny vacuum hoses near FPR




      Modified by RabbitsKin at 12:43 AM 2-8-2008

    2. 12-03-2007 01:45 PM #2
      hows the battery.

    3. Senior Member Dan J Reed's Avatar
      Join Date
      Jul 26th, 2004
      Location
      NJ - AKA - Earth's armpit.
      Posts
      26,507
      Vehicles
      Too many
      12-03-2007 01:48 PM #3
      If the car starts the battery is fine.
      Clean the TB, and ISV.
      Start from there.
      and if they are cheap (non OEM) parts in there, (plugs, wires, etc..) they are junk... swap-em out.
      Clean the MAF.
      Check the belt timing, often thats the cause of the CAM code.


      Modified by Dan J Reed at 6:50 PM 12-3-2007

    4. 12-03-2007 01:50 PM #4
      iac?


    5. Senior Member Dan J Reed's Avatar
      Join Date
      Jul 26th, 2004
      Location
      NJ - AKA - Earth's armpit.
      Posts
      26,507
      Vehicles
      Too many
      12-03-2007 01:50 PM #5
      ISV/IAC Idle Air control Valve, Idle Stabilizer Valve
      * OBDI cars only.

    6. Member
      Join Date
      Feb 11th, 2003
      Location
      Winchester, VA
      Posts
      9,236
      Vehicles
      964
      12-03-2007 03:12 PM #6
      Car is OBDII, TB is clean, parts were from GAP, belt teeth are spot-on (been running perfect all summer). Will definitely clean the MAF....would the theory there be that some whacked-out reading is causing the timing to be pulled so far that the car won't run? It runs fine after the first minute or so.
      The only other symptom has been a slightly erratic idle, which has kind of always been there, but the other day it almost died on me at a stop light. Never did that before, hasn't done it since.

    7. Member
      Join Date
      Feb 11th, 2003
      Location
      Winchester, VA
      Posts
      9,236
      Vehicles
      964
      12-03-2007 04:22 PM #7
      Cleaned MAF, cleaned TB, disconnected battery to reset codes. Still has a CEL, but we'll see how she does on cold starts in the next few days.


    8. 12-03-2007 05:04 PM #8
      Quote, originally posted by RabbitsKin »
      Could the camshaft position sensor be causing this?
      If the cps is bad the car will not start. I'm not sure if this sensor can slowly die though and possibly cause a rough idle.

    9. Member
      Join Date
      Feb 11th, 2003
      Location
      Winchester, VA
      Posts
      9,236
      Vehicles
      964
      12-03-2007 05:42 PM #9
      You know now that you say that, I'm wondering if I am remembering the right fault code. I had 5 of them, two of which were misfires.
      Update: after cleaning the MAF and TB, and clearing the codes, I took a trip down to Autozone to get the new codes read. P0131 and P1128, 02 sensor and MAF, so I'm guessing my MAF is just toast.

    10. Member
      Join Date
      Feb 11th, 2003
      Location
      Winchester, VA
      Posts
      9,236
      Vehicles
      964
      12-12-2007 08:33 AM #10
      Update:
      Got a good low-mileage MAF. Car ran beautiful yesterday, smoother idle than before. This morning is very wet, and the car was up to its old tricks again. VERY rough idle for the first minute, I could see and smell that the exhaust was very rich. I'm beginning to think it is the coil.
      Any thoughts?

    11. Member 2pt. slo's Avatar
      Join Date
      Jan 4th, 2004
      Location
      Creedmoor, NC
      Posts
      5,611
      Vehicles
      98' GTI 2.0T, 12' TDI SportWagen
      12-12-2007 10:24 AM #11
      Quote, originally posted by RabbitsKin »
      Update:
      I'm beginning to think it is the coil.
      Any thoughts?

      x2

    12. Senior Member Dan J Reed's Avatar
      Join Date
      Jul 26th, 2004
      Location
      NJ - AKA - Earth's armpit.
      Posts
      26,507
      Vehicles
      Too many
      12-12-2007 10:50 AM #12
      Coil.
      Spray it down with a mist of water see if it chokes.

    13. 12-14-2007 08:55 AM #13
      Bump im getting the exact same codes as you are. I got halfway to work today and my car was bogging so i decided to take it to autozone. He said that my 02 sensor was toast. Ive been told i have a bad cat and the autozone guy said that might be my culprit for all my misshaps. I just replaced the ignition coil and the coilpack so i dont think its that.
      Can a bad cat make my car bogg and die? Its only doing this when its really humid or the air is really wet. He also said my secondary air pump threw a code. thanks

    14. Member
      Join Date
      Feb 11th, 2003
      Location
      Winchester, VA
      Posts
      9,236
      Vehicles
      964
      12-14-2007 08:57 AM #14
      Only experience with clogged cats I've ever had was the opposite....it would bog at high rpm, but idle fine.

    15. Member cartercdad's Avatar
      Join Date
      May 13th, 2006
      Location
      pot hole central or PA
      Posts
      2,288
      Vehicles
      94. VW Golf- sold 01 durango R/T - totaled, 00 GTI VR6 picking up soon
      12-14-2007 08:57 AM #15
      i had a bad cat and it killed my o2 sensor and my coil was bad as well. get a new coil wires plugs new cat and o2 sensor. but check you cat before you buy one you should be able to see through it

    16. 12-14-2007 09:00 AM #16
      My cat is gutted. Its toast and i just replaced the cap not to long ago. I dont wanna buy new spark plugs because i have nuespeed ones. Are the nuespeed ones bad?

    17. Senior Member Dan J Reed's Avatar
      Join Date
      Jul 26th, 2004
      Location
      NJ - AKA - Earth's armpit.
      Posts
      26,507
      Vehicles
      Too many
      12-14-2007 09:36 AM #17
      Quote, originally posted by cartercdad »
      i had a bad cat and it killed my o2 sensor and my coil was bad as well. get a new coil wires plugs new cat and o2 sensor. but check you cat before you buy one you should be able to see through it

      Actually, the cat did not kill anything.
      The coil killed the O2 sensor (too rich) and that in turn also wiped out the converter.

    18. 12-14-2007 10:31 AM #18
      Do i need a new distributer?

    19. 12-18-2007 03:39 PM #19
      I have read several forums on this and was told it was the coolant sensor.
      Have you had any luck fixing the cold start issue?
      I have the same problem that when i start my car, it idles horribly likes its only hitting 2-3 of the cylinders, however when you give it a small rev, the problem goes away.
      I am taking it to VW today, but if you could post up the resolve to this issue, would be most appreciated.

    20. Member
      Join Date
      Feb 11th, 2003
      Location
      Winchester, VA
      Posts
      9,236
      Vehicles
      964
      12-18-2007 03:51 PM #20
      I have my new coil in-hand, will probably be putting it on tomorrow. It has a little door that opens near the 3-prong plug, revealing what looks like a fuseable link or set of contacts, which I think I will fill with silicone to prevent future moisture. I'll update the post with results.

    21. Member cartercdad's Avatar
      Join Date
      May 13th, 2006
      Location
      pot hole central or PA
      Posts
      2,288
      Vehicles
      94. VW Golf- sold 01 durango R/T - totaled, 00 GTI VR6 picking up soon
      12-19-2007 08:58 PM #21
      you know what i mean but yes that is what happened now i just ned to put on the new cat o2 and muffler

    22. Member
      Join Date
      Feb 11th, 2003
      Location
      Winchester, VA
      Posts
      9,236
      Vehicles
      964
      12-20-2007 03:23 PM #22
      Got the old coil out today, cracking everywhere:




      Here is a link to more pics:
      http://forums.vwvortex.com/zerothread?id=3598641

      Sealed up the NEW coil with silicone and some spray-on rubber coating. We'll see what happens when it dries. I guess removing my heat shield from the manifold wasn't such a great idea?




      Modified by RabbitsKin at 9:22 AM 12-22-2007

    23. Member
      Join Date
      Feb 11th, 2003
      Location
      Winchester, VA
      Posts
      9,236
      Vehicles
      964
      12-20-2007 03:40 PM #23

      Nothing. Not even the slightest change in the car's cold start behavior. Looks like I am back to square 1. I guess I'll clear the codes, have them read at Autozone and see if I am still getting an O2 sensor code.

    24. Senior Member Dan J Reed's Avatar
      Join Date
      Jul 26th, 2004
      Location
      NJ - AKA - Earth's armpit.
      Posts
      26,507
      Vehicles
      Too many
      12-22-2007 12:06 AM #24
      That coil is too far gone to save.
      Its arcing internally to its frame.
      I am sure of it.
      Nice pics tho.!

    25. Banned PELLA's Avatar
      Join Date
      Mar 4th, 2006
      Posts
      4,068
      12-22-2007 12:29 AM #25
      get thinner oil

    Page 1 of 4 1234 LastLast

    Posting Permissions

    • You may not post new threads
    • You may not post replies
    • You may not post attachments
    • You may not edit your posts
    •