windstar 96 3.8 error codes 171-174-304-1537

[frfpatty]

I was driving arround and I noticed the speed needle going up when I reached 40 miles/hour.The needle shot up to 60 miles for no reason.After a few minutes of driving the car started to drive very rough and it felt like it got stock on 2nd gear,also the car started sputtering. I slowed down but I noticed that the transmition was not shifting ,As I accelerated the rpm went up to 4000 and I did not feel or hear the transmition shifting to D.I went to the local shop and I got the following error codes 171-174-304-1537.After being in the shop for 30 minutes I drove back home and the problem was gone. After reading all the related postings, my concern is that the lost of vacuum would affect the gear shifting and the rpms or I may have a transmition problem besides the error codes.?

[wiswind]

Vehicle Speed Sensor (VSS)...do a search on that.
A defective speedometer can cause the shot up to 60 that you saw....and is a common fail item....but would NOT cause any shift issues...(I know that from experience with my '96).
I think that the VSS could, but I do not know from experience.

The other thing that can cause the transmission to act up is the Transmission Range Sensor (TRS) also called "neutral" switch. This switch sits on top of the transmission and is connected to the linkage of the gear select lever inside the car... This tells the computer what gear you have selected, and then the computer controls the shifting of the transmission.

The 171-174 codes are most likely vaccum leaks, or a dirty MAF (Mass Airflow Sensor). The MAF can be cleaned with non-residue electronic cleaner. The MAF is next to the air filter, when you unbuckle the air cleaner assembly, the air filter is in one part, ant the other part contains the MAF.
You look through the screen, and you will see a plastic bar that goes across the passage. There is a small hole at one end of the plastic bar. On the other side of the bar, is another hole....at the other end. You want to spray the electronic cleaner so that it goes into the hole that is facing you, and flows out the hole that is facing away from you. That will clean the sensors.

Make sure that everything is together without leaks in the air intake...from the filter to the throttle body.....INCLUDING the plastic tube that connects to the crankcase oil breather that is located on the front valve cover (on the '96 model year).

IF these are "P" codes......(verify that)

P0304 is a missfire for cylinder #4.
I had that....and was caused by clogged EGR ports.
They seem to clog closest to the EGR valve, and then you end up getting most of the EGR gases going into the ports that are the farthest from the EGR valve.....which would be Cylinders #1 and #4.

Another cause could be spark plug or spark plug wire.

Yet another possible cause could be a dirty fuel injector. I had to remove mine to clean it.....was crud built up inside the cup that is over the end of the injector that is in the lower manifold (the spray end). I was unable to clear it with fuel system cleaners....although I highly recommend a quality fuel system cleaner at LEAST a few times a year.

P1537 is Intake Manifold Runner Control (IMRC) Bank #1 stuck OPEN. There are a lot of threads on here about the IMRC system.
I would verify that they physically work correctly.
They will be OPEN with the engine OFF.
They will CLOSE when you start the engine.
A visual inspection with the engine at OFF may help.

The IMRC system moves the shaft with great force, so be careful of that as well.

Try to manually move each shaft to the closed position.....look for the stop that is mounted to the end of each shaft.....It should move from the OPEN stop to the CLOSED stop.....Verify this for each shaft....

Then see if they are closed with the engine ON at IDLE. (again, be careful as you are near the serpentine belt...and also, the vaccum puts a lot of force on the shafts that you are inspecting)

The IMRC actuator has 2 parts, a vaccum part, and an electrical part. The electrical part tells the computer what position the shaft is in.
You will want to make sure that the shaft can move to the fully closed position, there is a stop on the shaft....it is on the same end of the shaft as the actuator,.....hard to see...but it is there.

If the IMRC actuators are moving the shafts correctly, it is possible that you have an intermittent problem......binding of the shaft linkage.....clean, and a very small lubrication.
Or that the electrical portion of the actuator is defective.

If the shaft of one of them does not move from stop to stop, yet you are able to do so by hand, than the diaphram inside the actuator is defective....and must be replaced.
This is a dealer only part. A search on www.parts.com or....do a search through the forums for "5 star ford" as I saw them mentioned a few times as being good to do business with.