Taurus Car Club of America : Ford Taurus Forum banner
1 - 20 of 36 Posts

·
Registered
Joined
·
23 Posts
Discussion Starter · #1 · (Edited)
Hello Forum Members, I recently acquired a 2004 Taurus having 48K miles. The check engine light was on and my Bluedriver scanner indicated a coil C short. There was some hesitation but it drove well. The Bluedriver recommendation was to change the coil pack and I did with a Motorcraft equivalent. While waiting for the coil pack to come in I did some maintenance: changed the fuel filter and changed the spark plugs (Denso 4511 platinum, gaped to 1.1mm) and wires(AC Delco). I also spray cleaned the throttle with throttle/carb cleaner. I blew air onto the throttle area to try to remove excess cleaner.
I drove the car and it now has very low power. When I hit the accelerator to the floor it only goes 15mph. It was not having this problem before I worked on the car. I disconnected the battery overnight thinking the computer should be reset, but this did not fix anything. I am not reading any error codes with Bluedriver and the fuel rail pressure is reading is 40psi. I also removed the wires one at a time on the coil pack and I can observed strong rhythmic sparking on each port. Any suggestion on what I should check next? Thanks!

Motor vehicle Automotive design Automotive fuel system Vehicle Car
 

·
Registered
Joined
·
23 Posts
Discussion Starter · #4 ·
Updates: I tried the following since this initial post:
Checked the throttle position sensor using my Bluedriver scanner and saw a smooth increase in throttle position as I accelerated.
Checked the PCV and it looked clean and the metal ball valve moves freely.
The fuel pressure remains at around 40psi at idle and when driving.
I don’t believe it is a bad VSS because the speedometer seems to function OK.
I did a reset according to:
But still the car does not seem to be getting past first gear. It will only go up to about 15mph. Seems to idle fine.
Now I am thinking it might be the transmission solenoids? Or transmission position sensor?
I still do not get a check engine light coming on. The codes I am getting are B1208 EIC Switch-1 Assembly Circuit Short To Ground, U1900 Missing CAN Message from the HEC, and P1000 On-Board Diagnostic OBD Systems Readiness Test Not Complete.
 

·
Registered
Joined
·
23 Posts
Discussion Starter · #6 · (Edited)
Perhaps you accidentally damaged the PCM grounding strap while replacing spark plug #1.

Others can chime in, but does 15 mph at full throttle mean the PCM is in "limp mode"?
Thanks. I did have the battery disconnected while changing the spark plugs and wires and all maintenance work. But I can certainly check this to see if it is shorted or not.
 

·
Registered
04 Taurus SES Vulcan
Joined
·
162 Posts
[used scanner..]
I still do not get a check engine light coming on. The codes I am getting are B1208 EIC Switch-1 Assembly Circuit Short To Ground, U1900 Missing CAN Message from the HEC, and P1000 On-Board Diagnostic OBD Systems Readiness Test Not Complete.
You can ignore the P1000 it's just a status message that you haven't driven enough since last reset for self-tests to run. U1900 looks to be a loose or dirty obd port connector. B1208 is probably your culprit, somewhere in the Electronic Instrument Cluster switches or fuse.
 

·
Registered
Joined
·
23 Posts
Discussion Starter · #9 · (Edited)
Rectangle Slope Font Parallel Diagram


This is the response I got from the MAF sensor. At idle (~700 rpm) the value is about 0.7 lbs/min (5.3 g/sec) and at ~2700 rpm it was about 5.5 lbs/min (41.6 g/sec). I cleaned off the MAF sensor with mass sensor cleaner and the results didn't change. Also I removed the air filter and again the results didn't change significantly. Do these numbers appear to be OK? These results were measured when the transmission was set at park.

I looked over connections yesterday and I will check them again.
Also I drove the car around yesterday before I did this test (no performance improvements) and the only code now showing was a P1000.
 

·
Registered
04 Taurus SES Vulcan
Joined
·
162 Posts
the only code now showing was a P1000.
If you want that one to go away, the procedure for making sure all the monitors run is outlined here:
 

·
Registered
2000 Taurus SES 12v
Joined
·
934 Posts
So at 2700 rpm the fuel pressure is still around 40 psi?
What is the rpm when the car drives 15 mph with the accelerator to the floor?

Perhaps you were right initially, assuming something is wrong with the transmission and have a careful look at the connector of the TRS (Transmission Range Sensor a.k.a. Neutral Safety Switch).
It might be possible with your scanner to see what position the PCM thinks the transmission is in.
 

·
Registered
Joined
·
23 Posts
Discussion Starter · #14 ·
So at 2700 rpm the fuel pressure is still around 40 psi?
What is the rpm when the car drives 15 mph with the accelerator to the floor?

Perhaps you were right initially, assuming something is wrong with the transmission and have a careful look at the connector of the TRS (Transmission Range Sensor a.k.a. Neutral Safety Switch).
It might be possible with your scanner to see what position the PCM thinks the transmission is in.
The fuel pressure is around 40 psi at idle and when driving around.
The rpms go to about 3000 when flooring it at 15 mph.
I called my scanner's tech support and they said this scanner is not able to read transmission gear positions.

A sunny Sunday afternoon in the Netherlands. Everything quiet on the Eastern Front. Time for a nasty question!

Where did you buy the Denso plugs?
Greetings from the US. I purchased the Denso plugs from Amazon: https://www.amazon.com/gp/product/B00S3I3MMO/ref=ppx_yo_dt_b_asin_title_o07_s01?ie=UTF8&psc=1
 

·
Registered
2000 Taurus SES 12v
Joined
·
934 Posts
I purchased the Denso plugs from Amazon
Reason I was asking is because we had some discussions recently about counterfeit (a.k.a. fake) spark plugs. If you Google for "fake spark plugs" a new world will open for you. It seems Denso and NGK are very popular. Both have warnings on their websites. The funniest I read was that you can recognize a fake NGK plug because it says "Made in the USA" on the package (while of course these plugs are from Japan).
See for example


Not to accuse anybody here, but this Amazon seller is very small. Although this sounds far-fetched, you cannot rule out the new plugs are causing the problem, so if you didn't already throw out the old ones, ....
 

·
Registered
Joined
·
23 Posts
Discussion Starter · #18 ·
Reason I was asking is because we had some discussions recently about counterfeit (a.k.a. fake) spark plugs. If you Google for "fake spark plugs" a new world will open for you. It seems Denso and NGK are very popular. Both have warnings on their websites. The funniest I read was that you can recognize a fake NGK plug because it says "Made in the USA" on the package (while of course these plugs are from Japan).
See for example


Not to accuse anybody here, but this Amazon seller is very small. Although this sounds far-fetched, you cannot rule out the new plugs are causing the problem, so if you didn't already throw out the old ones, ....
This very interesting. Thanks for looking this up for me. I took a spark plug out and it seems to pass all the tests I gave it including the scratch test, scrutinizing the ceramic portion and electrodes, letter indentions and packaging. Liquid Fluid Plastic bottle Toy Gas
Finger Nickel Household hardware Tints and shades Electric blue
Household hardware Gas Audio equipment Lock Auto part
Household hardware Nickel Auto part Cosmetics Tints and shades
Tire Automotive tire Bicycle part Coil spring Rim
Material property Font Electronic device Electric blue Thumb
 
1 - 20 of 36 Posts
Top