Announcement

Collapse
No announcement yet.

Buckling, misfiring, hesitation

Collapse
X
Collapse
 
  • Page of 4
  • Filter
  • Time
  • Show
Clear All
new posts
Previous 1 2 3 4 template Next
    #1

    Buckling, misfiring, hesitation

    Hey guys, I need some help. I got an issue with the Mod Box that I am having trouble figuring out. Basically what happens is when I am driving and give it some gas I get hesitation, shudder and what sounds and feels like misfire. If I put it into neutral while driving and rev it, nothing. If it's in park and I rev it, nothing. I tried power braking it while parked and I can feel it missing. Weird thing is it doesn't start right off the bat. You gotta let it warm up before it starts doing it.

    So far, I swapped out all the plugs, COPs, cam sensor, crank sensor, DPFE sensor, MAF sensor. Found a burned out connector on the alternator so swapped the alternator out too. It appears to be temperature sensitive. The hotter it is, the worse it gets. Fuel pressure and vacuum both show correct readings. Also, no cel. Any ideas?

    Two things I should point out. When I went to a car show a few weeks back it sat out in the sun with the hood up. When leaving the show the battery light came on for a few minutes and went away which I thought was weird. Also, in the way home the car started to overheat. The faster I went, the hotter it got.

    Fast forward a week later after another car show. Same deal, it sat in the sun with the hood up all day. Leaving the car show I heard a slight hiss from the passenger side then all of the sudden it started to ping like crazy for a few minutes and went away. Once again, on the way home, same overheating issue as the week prior. When I got home I did a compression test fearing that I blew a head gasket. All cylinders checked out fine. I pulled the supercharger off and tried to get it running without the blower and was experiencing same symptoms as described earlier.

    I put the blower back on and it seemed to run better so I took it to another meet and noticed that it started buckling and hesitating when hot same as before.

    I haven't really driven it much since but today decided to see if I can fix it. Took it for a drive and it started to shutter and misfire pretty bad.

    I am kinda stuck scratching my head on this one. What really puzzles me is why it only does it when the car is in gear. In park on neutral the motor sounds perfectly healthy but as soon as you put it into gear it acts up.
    Tags: None
    #2
    no chance you have a dying injector is there? Might give just enough fuel to work unloaded, but not under load. I'd expect misfire codes on a specific cylinder, though those take some stupid large number of misfire events before it actually sets a code. If you can get the live data, that would probably tell you more.
    86 Lincoln Town Car (Galactica).
    5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

    91 Lincoln Mark VII LSC grandpa spec white and cranberry

    1984 Lincoln Continental TurboDiesel - rolls coal

    Originally posted by phayzer5
    I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

    Comment

      #3
      I don't think it's injectors because when I had the blower off I swapped the stock injectors and it was doing the same thing. I'll see if I can do some data logging.

      Comment

        #4
        It still sounds like a bad COP to me. Also, maybe look into changing the connectors to the COPs to the Granatelli ones. Seems to cure a lot of misfire and COP destroying issues. Common swap for the Marauder crowd.

        Quote from MM.net--> I was plagued with the same thing a few years back and the solid Granatelli connectors fixed it and I have not had a problem since!!!

        I still have all the OEM coils at 208K miles....give 'em a try!!
        These are highly engineered precision vehicles, the first step in diagnosing the problem is to strike the suspected offending part sharply and repeatedly with a blunt object, then re-test.

        Comment

          #5
          gadget73 thanks for the datalogging idea. Put a laptop on it, detected a misfire right off the bat. Swapped a COP, problem fixed.

          Comment

            #6
            Cool. Sometimes computers can be helpful. That is one thing I will definitely give to OBD-II, its a hell of a lot more powerful as a diagnostic tool than the old EEC-IV setup is.
            86 Lincoln Town Car (Galactica).
            5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

            91 Lincoln Mark VII LSC grandpa spec white and cranberry

            1984 Lincoln Continental TurboDiesel - rolls coal

            Originally posted by phayzer5
            I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

            Comment

              #7
              My 2000 MGM is missing really bad under acceleration but idles fine and is fine at speed..

              Are the COPs easy to swap?
              2000 Grand Marquis LS
              2000 F150 XLT 6 inches of lift.
              1987 Bill Blass Mark VII - Sold
              1985 Mercury Grand Marquis Colony Park- SOLD. to a little old lady
              Mercury Owners Group member
              Save The Whales, Restore an Old Station Wagon!!

              Comment

                #8
                What is a COP?
                1985 LTD Crown Victoria - SOLD
                1988 Town Car Signature - Current Party Barge

                Comment

                  #9
                  Coil On Plug


                  Sent from my iPhone using Tapatalk
                  2000 Grand Marquis LS
                  2000 F150 XLT 6 inches of lift.
                  1987 Bill Blass Mark VII - Sold
                  1985 Mercury Grand Marquis Colony Park- SOLD. to a little old lady
                  Mercury Owners Group member
                  Save The Whales, Restore an Old Station Wagon!!

                  Comment

                    #10
                    Originally posted by 85MercPark View Post
                    My 2000 MGM is missing really bad under acceleration but idles fine and is fine at speed..

                    Are the COPs easy to swap?
                    Yup. When you take the retainer bolts out, they move enough to clear the fuel rail. It would help to have a scanner to verify which cylinder(s) has the misfire so you can confirm it's the coil(s). I've actually been reading some stuff on CVN about the coils themselves rarely going bad, and that just changing the boots and springs might be all you need to do, though putting on a new set of COP's certainly wouldn't hurt if you can afford it.

                    2000 Grand Marquis LS HPP, a hand-me-down in 2008 with 128,000 km; 175,000 km as of July 2014
                    mods: air filter box 'tuba', headlight relay harness, J-mod (around 186,350 km), 70mm throttle body, KYB Gas-A-Just shocks, aluminum driveshaft, ARA3 PCM

                    Comment

                      #11
                      I read where the valve cover gasket leaking can foul the plugs... Mine does have a leak so hope it's not that...
                      2000 Grand Marquis LS
                      2000 F150 XLT 6 inches of lift.
                      1987 Bill Blass Mark VII - Sold
                      1985 Mercury Grand Marquis Colony Park- SOLD. to a little old lady
                      Mercury Owners Group member
                      Save The Whales, Restore an Old Station Wagon!!

                      Comment

                        #12
                        hAVE RUN INTO A LOT OF ISSUES WITH COP one guy used to stop in about every week needing a new coil until just about all of them were replaced on his expedition. The early ones were a issue remember discussing with one of the engineers about possible reasons / fixes for their issues.
                        Scars are tatoos of the fearless

                        Comment

                          #13
                          Originally posted by 85MercPark View Post
                          My 2000 MGM is missing really bad under acceleration but idles fine and is fine at speed..

                          Are the COPs easy to swap?
                          yes, one beer job.

                          1986 lincoln towncar signature series. 5.0 HO with thumper performance ported e7 heads, 1.7 roller rockers, warm air intake, 65mm throttle body, 1/2" intake spacer, ported intakes, 3.73 rear with trac lock, 98-02 front brake conversion, 92-97 rear disc conversion, 1" rear swaybar, 1 3/16" front swaybar, 16" wheels and tires, loud ass stereo system, badass cb, best time to date 15.94 at 87 mph. lots of mods in the works 221.8 rwhp 278 rwt
                          2006 Lincoln Town Car Signature. Stock for now
                          1989 Ford F-250 4x4 much much more to come, sefi converted so far.
                          1986 Toyota pickup with LSC wheels and 225/60/16 tires.
                          2008 Hyundai Elantra future Revcon toad
                          1987 TriBurner and 1986 Alaska stokers keeping me warm. (and some pesky oil heat)

                          please be patient, rebuilding an empire!

                          Comment

                            #14
                            Yes. But which one


                            Sent from my iPhone using Tapatalk
                            2000 Grand Marquis LS
                            2000 F150 XLT 6 inches of lift.
                            1987 Bill Blass Mark VII - Sold
                            1985 Mercury Grand Marquis Colony Park- SOLD. to a little old lady
                            Mercury Owners Group member
                            Save The Whales, Restore an Old Station Wagon!!

                            Comment

                              #15
                              with it idling... check for a "tapping" sound on the coil... if a coil is hopping or you can put a finger on it and feel the pulse each time it fires... it's probably the plug blowing by. The plug ceramic core is moving up and down and allowing blow-by and lack of compression. I've had this happen repeatedly on the PI engine in my 93. Use proper plat plugs for your engine. The coppers tend to fail that way. Had 4 fail that way on mine.

                              Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
                              rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
                              Originally posted by gadget73
                              ... and it should all work like magic and unicorns and stuff.
                              Originally posted by dmccaig
                              Overhead, some poor bastards are flying in airplanes.

                              Comment

                              Previous 1 2 3 4 template Next
                              Working...
                              X