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    strange shudder at low rpms

    when I am driving in my lincoln at like 18-23mph and 34-37 right around where gears change there is a shudder when i hit the pedal. in other words, when the car upshifts and the rpms go down, and then I give it gas, the whole car shudders until the rpms get up again, then its smooths out. Also my car is surging at idle, i really need a tach.
    1989 Lincoln Town Car - "Anabelle" - Original block, .030 over with SpeedPro pistons, rods fitted with ARP hardware, FRPP +volume oil pump, GT-40 3bar heads, Crane 1.72 rockers, 89' Fox cam, 93' Cobra lower intake, Explorer upper and 65mm TB, 93' Lightning EGR spacer, K&N intake kit from a 4.0L Ranger, 19lb/hr injectors w/ 87 Mark VII ECM, cat/smog deletes, Big Brake conversion, 3.55 K-Code Trac-Lok/Disc brake rear axle, CVPI LCA's w/1" sway bar in rear, wagon front sway bar, BBK 2.5" off-road H-Pipe, Flowmaster super 40s, HPP wheels, 3G alternator w/LMR.com wiring kit, gear reduction starter conversion, Best 1/4 time: 16.0 @ 85mph.

    #2
    Can you tell if it's in the engine or drivetrain? What about if you're sitting still in neutral and rev it?
    Nick
    88 Colony Park LS
    G-pa's old car, but he's cruisin around heaven in his 69 wagon now
    Future plans:Semi HO conversion, or Explorer motor swap, shift kit, PI springs and sway bars, KYB-GR2 shocks

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      #3
      sounds like ignition mis-fire to me, check the wires and make sure they are not arcing. If you didnt do a full tune up with the conversion, now is a good time to do it (cap, rotor, wires, plugs, fuel filter, 195 degree t/stat)
      2003 Town Car Signature - 3.27 RAR, Dual exhaust and J-mod - SOLD 9/2011
      89 Crown Victoria LX HPP -- SOLD 9/2010
      88 Grand Marquis LS - The Original -- Totaled 5/2006


      I rebuild AOD/AODE/4R70W/4R75E transmissions....Check out my Facebook page: https://www.facebook.com/pages/North...48414635312478

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        #4
        That is exactly what mine does, and I know what the problem is on mine. It's bad injectors. It may not be the same for you, but you can do a little diaging to maybe find out weather or not that is the problem.

        Your best bet is to take it to a shop and let them hook up the diag tool while they take it for a drive. They should be able to diag which one is bad if it is bad enough. If not, and it is a bad injector starting to go bad, they will at least be able to diag that it is one of the injectors. If you need a few good ones I have 6 of my original ones that are perfect, and less than 3000 miles ago they got a nice GF injector flush done to them at the shop.

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          #5
          it has new cap/rotor/wires/fuel filter/t-stat/ but the plugs that were new, were fuel washed and never were really right again. I'm going to check vacuum as well as timing to see if those are culprit.
          1989 Lincoln Town Car - "Anabelle" - Original block, .030 over with SpeedPro pistons, rods fitted with ARP hardware, FRPP +volume oil pump, GT-40 3bar heads, Crane 1.72 rockers, 89' Fox cam, 93' Cobra lower intake, Explorer upper and 65mm TB, 93' Lightning EGR spacer, K&N intake kit from a 4.0L Ranger, 19lb/hr injectors w/ 87 Mark VII ECM, cat/smog deletes, Big Brake conversion, 3.55 K-Code Trac-Lok/Disc brake rear axle, CVPI LCA's w/1" sway bar in rear, wagon front sway bar, BBK 2.5" off-road H-Pipe, Flowmaster super 40s, HPP wheels, 3G alternator w/LMR.com wiring kit, gear reduction starter conversion, Best 1/4 time: 16.0 @ 85mph.

          Comment


            #6
            Oh FYI, I replaced my fuel pump, filter, coil, wires and it had no effect on my problem. I also checked my vac lines as well. One thing to check is to uplug the vac line to the EGR valve and see if that has an effect, most likely will not.

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              #7
              Mine did this when I had the tv pressure set way low. You can tell if thats the problem tho because it'll shift way too soon. Could very well be fouled plugs. I've personally never had much good luck with plugs that had been seriously washed out. Replacing them would not be a bad idea, but check them first.
              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

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                #8
                TPS, possibly?
                1983 Grand Marquis 2Dr Sedan "Mercules"
                Tremec TKO conversion, hydraulic clutch, HURST equipped!

                Comment


                  #9
                  have you checked for trouble codes since the HO conversion was done?
                  I would check for codes.

                  it also sounds very much like you have a vaccum leak or leaks.
                  2003 Town Car Signature - 3.27 RAR, Dual exhaust and J-mod - SOLD 9/2011
                  89 Crown Victoria LX HPP -- SOLD 9/2010
                  88 Grand Marquis LS - The Original -- Totaled 5/2006


                  I rebuild AOD/AODE/4R70W/4R75E transmissions....Check out my Facebook page: https://www.facebook.com/pages/North...48414635312478

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