Yo Skitter,
Is Transmission Control Indicator Lamp flashing while driving? If the transmission control indicator light is flashing on and off repeatedly, the transmission system is malfunctioning. The transmission will operate in a failure management mode with harsh engagements, firm shift feel, and abnormal shift schedule.
is CEL On while driving? Do a code test anyway. See
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Torque Converter Operation Test : If the shudder occurs a) during the 3-4 or 4-3 shift at HEAVY throttle, or B) at 40mph in 2, OD OFF, and OD, or c) at the same RPM in every gear, or d) coasting, cruising, or in R, or e) during extended light braking, then it is NOT TC clutch shudder; The following is a list of common vehicle concerns that have been misdiagnosed as torque converter clutch shudder. For diagnosis of the following items, refer to the appropriate sections of the workshop manual and the Powertrain Control/Emissions Diagnosis manual (PCED). Spark plugs - check for cracks, high resistance or broken insulators. Plug wires. Fuel injector - filter may be plugged. Fuel contamination - engine runs poorly. EGR valve - valve may let in too much exhaust gas and cause engine to run lean. Vacuum leak - engine will not get correct air/fuel mixture. MAP sensor - improper air/fuel mixture. HO2S sensor - too rich/lean air/fuel mixture. Fuel pressure - may be too low. Engine mounts -loose/damaged mounts can cause vibration concerns. Axle joints - check for vibration..."
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Misfire PERPETRATORS:
Are plug wire routed as shown on decal atop radiator support?
Spark Plug Wire Routing & Firing Order TSB 94-04-10 for 87-93 5.0 & 94-96 5.0
& all 5.8 - engine miss, spark knock, buck/***** surge and other driveability concerns;
MIESK5 NOTE; The firing order for 1994 5.0Ls &
all 5.8Ls is 1-3-7-2-6-5-4-8.
Distributor rotation: Counterclockwise
On these vehicles the #1 and #3, or #5 and #6 spark plug wires must be separated to eliminate the possibility of an induction crossfire. To eliminate the possibility of the coil wire becoming disconnected, route the coil wire under the spark plug wires at the distributor cap. Source: by Ford
http://www.supermotors.net/clubs/superford/registry/5180/32495 by tank92
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Could be due to a problem with the EGR system (other than the valve itself) causing the engine to misfire
under load. Suspect vacuum leak or faukty EVR, EVP or stuck EGR valve.
¿
Vacuum leak, see my
leak diagnosis link in post #11
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Air filter, is it relatively clean?Air inlet atop radiator support to filter box and to throttle body; look for obstruction; damaged or opening in tubing after the filter box.Fuel quality; Oxidized fuel often turns darker over time and may even smell sour. You can check stored gasoline by pouring some into a clear glass container and comparing it side-by-side with known fresh gasoline. If your old sample looks noticeably darker than the fresh gas, you have strong evidence the gas has gone bad.
Al