2001 3.8l running rough, help????

Discussion in 'SN95 V6 Mustang Tech' started by valleystang11, Jan 2, 2010.

  1. I have a 2001 3.8l and its running rough. I recently put in a CAI but its way to cold out to run it, so i replaced it with the stock one. All the time when i ran the CAI my stang was jumpy. It would jump in increments and would shift high. I cant figure out whats wrong. It also boggs out when stepped on, and my whole car shakes. Could this be water in my gas lines? or maybe a cylinder not firing? I just need some advice from an expert.
    Any Help would be greatly appreciated!!!!
  2. I recently had the same problem, my coil quit firing on the number two cylinder. I replaced the coil & the problem was solved. Do a little trouble shooting first though.
  3. i dont know alot but my car did the same thing and it was my coil pack. reading your question i noticed you said you do not have your cai on cause the cold weather. is it bad to run it with one in the cold? i just recently put one on mine

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  4. Had a similar issue as well, took my car to Schuck's/O'reilly auto parts and plugged it into their OBD2 reader & it was a misfire changed all the plugs & wires still had the issue then changed out the coil pack & I was good to go. Take a look at my thread "misfire on cylinder 1" and another fellow told me how to test my coil.
  5. CAI if all sensors were hooked back up should not make a difference if its cold weather
  6. your CAI will run much better with colder air man. put it back on and double check ALL your sensors. my 01 with K&N full CAI ran funny till i noticed one of the sensors wasnt in the hole all the way
  7. Check for a vacuum leak. Even a tiny leak will cause problems.

    Check all lines, hoses, connections, PCV lines, oil dip stick, valve cover gaskets. Since recent work has been done on the CAI, start there.

    Clean your MAF. Use cleaner made to clean the MAF. It is delicate and easy to damage. Be careful.

    If there are any check engine lights (DTC's), have an auto parts store pull the codes and post the full code.

    It has already been mentioned to check your spark plugs and coil packs.
  8. Similar issue, please help

    I have an 01' v6 that is also "bogging" down if you will. The idle is real rough and when you step on it you get that sputtering, however sometimes it will start to sputter then for no reason what so ever go like theres no problem. I have had the codes run at a local store and it came up with both a lean and rich condition on bank 2. I've already changed the plugs, ran a bunch of cleaner through and nothing. If i unplug the battery for a bit to reset the check engine it seems to solve the problem temporarily, but eventually comes back. any one have any insight?
  9. Have you cleaned the MAF?

    Consider changing the front O2 sensors. If money is tight, change the front O2 sensor on the left hand side.

    The Lean code is almost surely a vaccuum leak. Check for an exhaust leak as this can cause a lean DTC as well.
  10. CAI

    it is better to run it in cold weather...Hence the name COLD AIR intake!!!!
  11. change your plugs and wires,and if that fails, check your coil pack, i had the same problem, i replaced the wires and plugs,and drained the gas tank,put some fuel injector cleaner in it, and it runs like a dream,

    and the cool air intake can go back on, its called that for a reason, it makes it run better, i have mine on and my car fires up first time everyday, and runs great!
  12. UPDATE!!!!!!

    heres an update, I had it inspected, and coil pack is good, wires are brand new, distributor good, havent got around to check PCV lines, ALTHOUGH when I did put on the CAI i accidently pulled a line from the side of the stock intake, i made sure to put it back on but it slides off pretty easy. Also that hose is withered towards the top a little bit.
    I haven't checked the MAF yet but My mechanic elimated all possibilties except o2 sensor. Could a o2 sensor possibly create this much of a problem???

    He also mentioned that the tps could have something to do with it also.
    I have been barley able to get up my arched driveway because when i look for the low power it doesn't respond and just shakes, I have no idea where to go to now.
  13. Are you paying this mechanic? Were you told the distributor was good?

    A 2001 does not have a distributor. :doh:

    A bad TPS sensor is not known to cause a 2001 to run rough. It may cause a high/rolling/eratic idle, slightly poorer throttle response, or poor WOT response.

    Today's cars simply will not run right with even a tiny vacuum leak. Replace any/all vacuum lines that are soft/hard/weak/brittle/split/oil soaked. Inspect all PCV lines, oil dip stick, oil filler cap, intake lines/couplings, or any place air can enter.

    This may be bad O2 sensors. But if this car has over a 100k miles, consider replacing. At the min, it will improve the fuel mileage.

    Normally rough running is misfire (fuel or spark). However, it can be MAF, CKP, CAM sensor, amoung others.

    Under what driving conditions is the car running rough? Idle, crusing, WOT. Does it happen all of the time, only when hot/cold? Certain speeds? Did it run rough before the CAI was installed?

    There is also a Ford TSB that may apply. It deals with an incorrectly installed cam sensor.

    Engine Controls - Engine Surge/Rolling Idle/DTC's Set

    Article No.




    1994-1997 THUNDERBIRD
    1995-2003 TAURUS
    1996-2003 MUSTANG
    1995-1997 AEROSTAR
    1995-2003 RANGER, WINDSTAR
    1996-2000 EXPLORER
    1997-2003 E SERIES, F-150

    1994-1997 COUGAR
    1995-2003 SABLE
    1997-2000 MOUNTAINEER


    Incorrectly installed gear driven camshaft position (CMP) sensor synchronizer assemblies may be hard to diagnose. Vehicle may exhibit poor fuel economy, driveability Diagnostic Trouble Codes (DTCs) P1336, P1309, P0340 with MIL light on. Loss of power, surge, hesitation and runs rough on acceleration may also be present.


    New diagnostics have been developed for WDS to diagnose incorrectly installed gear driven camshaft position (CMP) synchronizer assemblies. Refer to the following Service Procedure to diagnose a possible mis-installed synchronizer assembly and proper installation procedure.


    Items Covered In This Article

    ^ "Hall" vs. "VRS" sensor function
    ^ Vehicle history scrutiny for past service of the synchronizer assembly
    ^ WDS - Power balance test
    ^ WDS - CMP and CKP wave signal comparison
    ^ Wave Comparison chart - CMP vs. CKP
    ^ Correct (CMP) synchronizer installation tool application & installation procedure
    ^ "Top Dead Center" (TDC) alignment
    ^ Synchronizer installation tool application chart

    Hall - Effect (Hall) and Variable Reluctance (VRS) CMP Sensors

    CMP sensors are used on all current model year engines, regardless of fuel system or ignition system type. The CMP sensor provides the Powertrain Control Module (PCM) with cam position information to indicate # 1 cylinder, on the compression stroke

    There are two different types of CMP sensors:

    ^ The three-pin, Hall-effect sensor (Figure 1)
    ^ The two-pin Variable Reluctance sensor (Figure 1)

    Although the Hall-effect (three-pin) and the Variable Reluctance (two-pin) CMP sensors perform the same function, their signal appearance is quite different and they are not interchangeable.

    ^ The three-pin Hall-effect sensor uses a Hall effect device and a magnet to generate a digital square wave signal (Figure 2)
    ^ The two-pin Variable Reluctance sensor is a magnetic transducer, which uses differential voltage across windings to generate a voltage waveform that is similar to a sine wave (Figure 2)

    Both sensors provide a switching voltage as the engine rotates.
  14. Good advice so far.......
    A shaking engine normally means a chronic case of misfire. You should get P03XX codes if this happens for any length of time. If you have water in your gas ,yes it will make the engine want to die (water does not burn too well). Water is also heavier than gas so it will sink to the bottom of your gas tank & get scavenged into the fuel pump quickly. You might try some gas line Antifreeze to see if this improves the situation, best to keep your gas tank near full in really cold conditions.
    Keep us updated !
  15. hey dude can u look at my post : Hi, Can someone help me with 2000 V6 mustang?
    I have no current coming out from coil pack for 3 and 4 ONLY. i changed the coil but same problem. What should i do? do i need to reprogram the computer since the computer and all the harnesses i got from another 1999 mustang and put it in mine 2000 mustang with v6 motor. it starts good and drives but slow.
  16. 2000 Mustang 3.8 351 code new coil doesn't fix

    I replaced my coil at a autozone parking lot after car started running rough and actron tester at autozone showed code 351. Ran fine for three days, then did same thing. Exchanged autozone coil for new one same rough idle, took back original coil and autozone coil back and both old and new tested good on ohmmeter from their autozone testing book. They sold me a ignition control module, which I today found out isn't used on my car. Returning it, and buying some new vacuum lines because I saw one that, from exhaust sensing line was going to a sensor at rt front of motor was split, also going to buy new O2 sensors as car has over 100 k miles and I believe original O2 sensors. I'll do the test between WH/LB and the DB/LB, and also the WH/LB and RD/Lb wire also. After that if I can't fix problem, should I try a junkyard ECM or give up and go to dealer, because the junkyard computer won't recognize my key?
  17. P0351 Through P0360 - Ignition Coil driver

    inspector8, FWIIW, always post the full DTC codes.

    For the P0351, the "1" indicates there is a problem on the #1 cylinder circuit. This should be the DB/LG return wire.

    Please look at the attached diagram. Note that the primary ignition circuit is a ground start circuit. Recommend confirming the the wire path back to the PCM is good. Inspect all wires and connectors. Look for bent or pushed pins. Clean any signs of water damage. Test with a "noid" style test light. The light should pulse each time the coil is fired. Test all 3 circuits to confirm that the tester is working.

    If the wire path from the coil to the PCM is good, then there is a stong possibility that the coil driver circuits in the PCM are bad. It is possible for the DIYer to replace the PCM. However, there is the issue of the anti-theft system.

    One option is to disable PATS with a tuner (SCT or the like).

    Another option is to replace yourself and tow the car to the dealer.

    For salvage PCM, try searching car-part.com. There is a possibility that Autozone sells a replacement PCM with PATS disabled.

    P0351 Through P0360 - Ignition Coil A through J Primary/ Secondary Circuit Malfunction

    Each ignition primary circuit is continuously monitored. The test fails when the PCM does not receive a valid IDM pulse signal from the ignition module (integrated in PCM).

    • Open or short in Ignition START/RUN circuit
    • Open coil driver circuit in harness
    • Coil driver circuit shorted to ground
    • Damaged coil
    • Damaged PCM
    • Coil driver circuit shorted to PWR

    Attached Files:

  18. 351 code is for cyl #1

    Thanks for the info and very quick reply. However I think you meant to attach 21-3 Engine ignition diagram I copied for another thread, am I correct?:shrug:
  19. Actually I ment to attach diagram 21-4 which is for the 3.8 engine coil pack. Updated the original post. Sorry.
  20. diagram

    Thanks so much, I also bought a Haynes manual today.:nice: