4EOD Tach Sensor - Diesel Forum

huskiemobileman · 05-30-2006, 08:44 AM

Where is it located and what does it look like? Thanks.

Mr_Roboto · 05-30-2006, 11:57 AM

This pic shows the location: http://photos.thedieselstop.com/show...amp;thecat=998

I couldn't find a pic that showed the actual sensor, that pic is from an early C6 truck without a tach.

Where that plug is is where your tach sensor is. It is a 1" nut with 2 wires coming out. Make sure you unhook the connector before removing the sensor. Ford dealer part only "RPM sensor".

huskiemobileman · 05-30-2006, 01:59 PM

Stupid question, but my van does not have a tach, so would it have that sensor? I am having the typical O/D light flashing on and off and the tranny is shifty between 20 and 40 mph when cold. Where exactly on the engine is the sensor?

Where do you get the trouble codes from on the transmission? Thanks.

pafixitman · 05-30-2006, 02:24 PM

E4OD gets input from 3 sensors - tach (probably has a technical name) fipl (fuel injection pump lever) and speed (RABS) sensor on the top of the pumpkin.

The dead tach sender should/would send the automatic trans into a "failure management mode" (limp mode) with harsh engagements and firm shift feel, and an abnormal shift schedule. It has no effect on a manual trans only the Tach readings.

Replace the tach sender on the oil fill housing a big 1" nut with 2 wires. Ford only part Engine RPM sensor E5TZ-17B384-A about $50. You can remove and clean it but usually changed later too. You can test it too, hold it in the air away from ferrous metal, using an ohm meter lead on each wire you need DC resistance between 2000-3000 ohms.

The TP (FIPL) sensor is incorporated to provide an electrical signal, which is proportional to the amount of fuel being delivered, as an input to the Transmission Electronic Control Assembly (TECA) Based on this information, the TP (FIPL) provides the proper shift scheduling and torque capacity.

Should a malfunction occur in the TP (FIPL) sensor circuit, the electrical signal sent to the TECA will be recognized as erroneous. When this out-of-specification signal is detected, the TECA will provide a high-capacity operating mode that protects the transmission from potential damage. This operating mode includes maximum TV pressure, resulting in harsh upshifts and engagements and a singular shift schedule regardless of accelerator pedal position, resulting in the 1-2, 2-3 and 3-4 shifts occurring at a speed commensurate with a heavy (but not wide open) throttle setting.

The Ford shop manual has a procedure to set the FIPL sensor. It's fairly long and required a special guage block and the use of the Super Star Tester ( early scan tool ). I decided that this was not what the "field" needed so I called the Ford Hotline and they gave me plain and simple voltage readings at closed throttle and WOT. MUCH easier.

Closed throttle voltage = 1.1V
WOT min 0f 3.8V not to exceed 4.3V

You definitely don't want 5V at WOT. PCM would read this as a short between Reference Voltage ( 5V ) and FIPL signal and go into failure mode.

Fluid level, loose connections can also cause limp mode. The test port is on the driver side fender near the fire wall. Wally world has the scan tool.

huskiemobileman · 05-30-2006, 03:03 PM

I found the scanner here: http://www.etoolcart.com/index.asp?P...mp;ProdID=3758

But it specifies:

1985 - 1994 Trucks & Vans Engine Size
2.3 Liter Excludes Diesel Models
2.8 Liter E & F Series - Vehicles under 8500 lbs. only
2.9 - 5.8 Liter All Vehicles
7.3 Liter Excludes 1994 Models
7.5 Liter All Vehicles

Any help?

Mr_Roboto · 05-30-2006, 04:34 PM

They likely "exclude" 1994 because that year you could get either a IDI or a Powerstroke. Rather than try to specify one of two engines with the same displacement, they exclude the year. That way there are no complaints when it does not work properly with a 1994 PowerStroke.

I also have a scanner that "excludes" 1994, it works fine with my 1994 vans.

ltaylor · 05-30-2006, 11:19 PM

my 92 was acting the same as you describe. but my tach would fall to ZERO when it was idiling, so i put a new one in fixed my tach and fixed the odd shifting

huskiemobileman · 05-31-2006, 08:43 AM

[ QUOTE ]
They likely "exclude" 1994 because that year you could get either a IDI or a Powerstroke. Rather than try to specify one of two engines with the same displacement, they exclude the year. That way there are no complaints when it does not work properly with a 1994 PowerStroke.

I also have a scanner that "excludes" 1994, it works fine with my 1994 vans.

[/ QUOTE ]Thanks for the info!