THIS IS NOT MY WRITE UP. I CANT REMEMBER WHO WROTE IT OR WHERE I GOT IT FROM.
• TECA, PCM, TCM: these all refer to the computer. TECA is transmission electronic control assembly, PCM is powertrain control module, and TCM is transmission control module.
• TECA relay: Referred to as the EEC relay by most autoparts stores, it switches power to the TECA and sensors when the key is on
• VSS sensor: Vehicle speed sensor. 91 and older it's located on the trans tailshaft with a cable going through it to run the mechanical speedo. 92 and up use the rear ABS sensor, sometimes referred to as the VSS sensor at autoparts stores
• FIPL: fuel injection pump lever sensor, also referred to as the TPS (throttle position sensor) by autoparts stores. It tells the computer how much the throttle input is
• MLPS: manual lever position sensor. It's also referred to as the TRS (transmission range sensor) and it tells the computer what gear is manually selected (PRND21)
• Tach sensor: located on the timing gear cover, indicates engine speed to the computer
• TFT: transmission fluid temperature sensor, it's part of the solenoid pack
• SS1: shift solenoid one
• SS2: shift solenoid two
• TCC: torque converter lockup clutch
• CCS: coast clutch solenoid, controls the coast clutch to allow some engine braking on deceleration *See MLSC's post below*
• BPS: barometric pressure sensor, indicates altitude to the computer
• EPC: electronic pressure control solenoid, located in the solenoid pack, controls shift firmness.
• PSOM: programmable speedometer/odometer module. On 92 and up it converts the rear ABS signal into a VSS signal for the trans. It's also the speedometer as it is attached to the rear of the speedo gauge.
The most handy piece of equipment to have is an old style Ford EEC-IV code reader, or an newer code reader that can hookup to the old style EEC-IV diagnostic terminals. Codes can also be read with a test light or a multi meter. If your trans is acting funny the first thing to do is get the codes! The second thing to do is remove and replace the connectors on the trans, clean off any corrosion. The problem could be as simple as a bad connection. If there is no automatic control then either the trans isn't getting power, the sensors aren't grounded at the pass. side battery, or the solenoid pack is burnt. It doesn't hurt to pull the pan not only to check condition of the fluid but to do a fluid and filter change. If you do it wouldn't hurt to unbolt and remove the solenoid pack and give it and it's connector a good cleaning.
Now just throwing sensors at the problem can get expensive so again it's best to get the codes. 92 and up used an upgraded MLPS and the connector is different, most parts stores will sell it with a pigtail connector or a new connector body that the terminals from your old connector snap into. If this is bad all sorts of things can happen, no OD, no converter lockup, dropping in and out of lockup or gear, etc.
There are posts all over this board about the FIPL, make sure you have the newer grey style. FIPL should be 1.1 volts in the closed position and no more than 4.5 volts at WOT. This is meaured by sticking a probe on the middle wire and the other to ground, then manually move the throttle from idle to full slowly looking not only for min/max but also bad spots in the range.
The VSS signal tells the trans when to shift as well as lockup the converter. If it's bad or open the converter may not lockup and the trans takes forever to upshift, almost like it's slipping. I believe a bad tach signal can do the same thing.
I have always used volts measured off the center wire on the tps switch leads. On a warmed up engine key on but engine off I prefer a voltage of 1.2 volts. Factory suggests .96 to 1.2 volts. We can't do anything about adjusting the high voltage. When we set the idle voltage and then go wide open throttle the wot is what ever we get. What we can't have it 5 volts at wide open throttle position. That will cause the trans computer to short out and we end up in limp home mode and thats really ******* the trans
