Taurus Car Club of America : Ford Taurus Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
Hello, I'm new to the forum and need some help. My 2000 Sable (duratec) has been showing the following codes, P0171,P0174,P0303 and runs rough on cold mornings. Runs fine every other time. The rough running time is specifically after the engine idle speed has dropped of after the initial start. It sound just like it's going to stall. Before you make your diagnosis, Let me give you the info on what has been replaced as parts of normal maintenace and repair before the codes. Plugs, Coil Boots and Springs (2 months old) and fuel filter(brand new). After codes occurred, Pcv valve (auto zone) and new Pcv hose(ford dealer). After reading the Wiki, I determined it was leaking(oil contamination from pcv valve), thus the new hose. I have checked for vaccum leaks at the hoses and anything I thought was potentially leaking it was cleaned and a hose clamp was applied at the fitting to ensure a tight seal. I have cleaned the MAF sensor and Throttle body. My fuel pressure at idle is 31 psi and when it is about to stall it inclines to 35 psi. Is this pressure to low for my Sable? (My haynes book says it's within range?)

Misfire info- To ensure Coil #3 is good I swapped it with another and the misfire did not jump to the new cylinder. Just for peace of mind, I installed a new plug in #3. Old one that came out looked fine, no oil normal coloring of used plug. I'm thinking injector now but the intake has to come off and that's just more fun. :angry: I have added some lucas fuel injector cleaner but that will take some time to work through the system.

Could the egr valve be stuck open or defective? I will see if it holds vaccum. Could this be the cause of my problem? Egr sensor? No Egr codes showing although. Anyone know what range of values it should show?

MAF- I use a K+N air Filter.Could the oil in the filter have damaged the MAF and it's sending readings out of range. Does anyone know the test procedure and values?

O2 sensors? Now have 145,000 on car and on them. I doubt they all went bad at once but I'm really lucky like that. :D

Any help is most appreciated, I'm about to buy a shotgun! :angryfire:

Mike
 

·
Registered
Joined
·
53 Posts
Hello, I'm new to the forum and need some help. My 2000 Sable (duratec) has been showing the following codes, P0171,P0174,P0303 and runs rough on cold mornings. Runs fine every other time. The rough running time is specifically after the engine idle speed has dropped of after the initial start. It sound just like it's going to stall. Before you make your diagnosis, Let me give you the info on what has been replaced as parts of normal maintenace and repair before the codes. Plugs, Coil Boots and Springs (2 months old) and fuel filter(brand new). After codes occurred, Pcv valve (auto zone) and new Pcv hose(ford dealer). After reading the Wiki, I determined it was leaking(oil contamination from pcv valve), thus the new hose. I have checked for vaccum leaks at the hoses and anything I thought was potentially leaking it was cleaned and a hose clamp was applied at the fitting to ensure a tight seal. I have cleaned the MAF sensor and Throttle body. My fuel pressure at idle is 31 psi and when it is about to stall it inclines to 35 psi. Is this pressure to low for my Sable? (My haynes book says it's within range?)

Misfire info- To ensure Coil #3 is good I swapped it with another and the misfire did not jump to the new cylinder. Just for peace of mind, I installed a new plug in #3. Old one that came out looked fine, no oil normal coloring of used plug. I'm thinking injector now but the intake has to come off and that's just more fun. :angry: I have added some lucas fuel injector cleaner but that will take some time to work through the system.

Could the egr valve be stuck open or defective? I will see if it holds vaccum. Could this be the cause of my problem? Egr sensor? No Egr codes showing although. Anyone know what range of values it should show?

MAF- I use a K+N air Filter.Could the oil in the filter have damaged the MAF and it's sending readings out of range. Does anyone know the test procedure and values?

O2 sensors? Now have 145,000 on car and on them. I doubt they all went bad at once but I'm really lucky like that. :D

Any help is most appreciated, I'm about to buy a shotgun! :angryfire:

Mike
[/b]
Hi Mike
I have the same problem only i have no codes. I have 143000 miles on my 2000 sable duratec.
I'll be watching to see what kind of replies you get.
Greg
 

·
Premium Member
Joined
·
9,959 Posts
It's generally recommended to replace O2 sensors every 75k miles.

Vacuum leaks are the most common cause of the P0174 and P0171 combined codes.

Have you re-oiled the K&N or is it still original? I've never had a problem with them, but they can cause issues if oil gets on the MAF sensor.

31psi seems low. IIRC pressure should be between 40-55psi, although I have not looked at the specs for the 2000. Low fuel pressure could cause all of these problems.
 

·
Registered
Joined
·
3,686 Posts
It's generally recommended to replace O2 sensors every 75k miles.

Vacuum leaks are the most common cause of the P0174 and P0171 combined codes.

Have you re-oiled the K&N or is it still original? I've never had a problem with them, but they can cause issues if oil gets on the MAF sensor.

31psi seems low. IIRC pressure should be between 40-55psi, although I have not looked at the specs for the 2000. Low fuel pressure could cause all of these problems.
[/b]
It would be 40-55 if he disconnect the vacuum line from the regulator. With the vacuum line installed, pressure will be lower. 31 doesn't sound too bad.

O2 sensors will not cause those codes, so don't worry about them for now.

Double check for vacuum leaks, and even tho you don't want to, you could try swapping the #3 injector with another one, and see if the misfire code goes too. You may have more than one issue, but it's possible that the lean condition is also causing the misfire.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #5
Here's an update- I checked the EGR valve with hand held vacuum gauge, engine off it held vaccuum. Engine on at idle it started running rough just like when it's cold. So I'm thinking no EGR problem. I'll leave the valve and sensor alone for now.

Yesterday I cleared all the codes but since it's been cold here in the northeast car is running rough as ever at start. Now I have 5 codes stored! po171,po174,po303, po301,p0302. Hmmm. and the best part which I know is totally unrelated- The power windows, powers mirrors and interior lights are now not working! Must be a fuse or something but it just add insult to injury at this point. This all happened when car was stalling today. (Life's great sometimes isn't it!) :rolleyes:

Nidan said in another post , only use a Ford pcv valve. Anyone else had trouble with aftermarket? Maybe I can get a ford one tomorrow.

Any special instructions to take the intake manifold off or re-install? I know I'll need some gaskets.

Did anyone notice how posts of 2000 duratec owners cars are running roughly lately? Ford will certainly survive a long time in this economy- strictly on service and parts income alone! All kidding aside, thanks everyone.



Mike
 

·
Premium Member
Joined
·
9,959 Posts
Did anyone notice how posts of 2000 duratec owners cars are running roughly lately?

Mike
[/b]
I did notice and thought "what an odd coincidence." 2000 Taurus Duratecs are a single year revision, so they may have individual issues not associated with other years.
 

·
Premium Member
Joined
·
138 Posts
Exactly the same problem with my 01 24v Sable.

Just changed the PCV and PCV hose today, and it was really difficult to change them. almost 2.5 hours labor in near frozen temperature.

The old hose is really bad, and it is almost totally clogged. I thought I found the culprit. but, rough idling is the same. I have no idea now.

I also have the code p0171 and p0174.
 

·
Registered
Joined
·
24 Posts
Chalk up another 2000 Duratec with recurring p0171 and p0174 codes.

If you have missfire codes along with the p0171 and p0174 codes, then you need to resolve those two codes first. In many cases the missfire codes are a symptom of the lean codes. If you replace the PC valve make sure you replace both the connecting hose and the upper elbow hose going into the intake. The elbow hose is notorious for developing a split that is hard to see when on the car.

The rough and low cold idle that resolves after warm up, with or without the p0171 and p0174 codes, are indicative of a vacuum leak with the upper and lower intake manifold gaskets.

I have chased that cold idle problem after replacing the PC valve and entire hose assembly. The p0171 and p0174 codes returned after a month or two. The rough and low cold idle also triggered some random missfire codes. The missfire would be expected since the lean condition caused by unmetered air would generate misfires especially during a cold start warmup.

I initially did not suspect the UIM gaskets, as I could not detect a leak form there. The car had only 70,000 miles and the UIM had never been removed, nor were the bolts loose. However, after I removed the UIM I could see where they were leaking on the inside part of the runner. Due to how the gaskets had deteriorated, they should be considered a wearable item, even though the UIM has never been disturbed.

After I replaced them the problem was resolved, but only temporarily, it has now returned. My mistake was not replacing the lower intake gaskets, which I am about to do now. I regret not doing both UIM and LIM gaskets, however, I originally did not suspect them since I could not detect the leak, and only bought the UIM gaskets from the dealer on spec prior to removal. There is a Felpro aftermarket set that contains both for around $20. I originally replaced the PCV valve and hose assembly without removing the intake. I used a spark plug socket and long extension by hand to remove the PCV valve.

In hindsight, I would recommend UIM and LIM gasket replacement in addition to the PCV valve and assembly hoses for those symptoms. I never suspected that virgiin non removed gaskets could end up leaking undetected on a 70,000 mile engine. Also, make sure you follow the service manual procedure for both the bolt tightening specs, and especially the sequence on the UIM.

Here is a recent example post: http://www.taurusclub.com/forum/index.php?...mp;#entry675380 from this thread: http://www.taurusclub.com/forum/index.php?showtopic=62342#
 

·
Registered
Joined
·
125 Posts
Hey all- I have the exact same problems as the OP. 2000 Taurus, 3.0 Tec. Throwing codes 171,174,303 (and at one point all 5 he mentioned). I corrected this before by replacing the PCV elbow (which was a crap design from Ford to begin with). I'm afraid....with 204k miles....it's my UIM and LIM gaskets. I'll be swapping fuel filters and gaskets in the near future, I'll keep everyone updated
 

·
Registered
Joined
·
10,096 Posts
Exactly the same problem with my 01 24v Sable.

Just changed the PCV and PCV hose today, and it was really difficult to change them. almost 2.5 hours labor in near frozen temperature.

The old hose is really bad, and it is almost totally clogged. I thought I found the culprit. but, rough idling is the same. I have no idea now.

I also have the code p0171 and p0174.
Sorry for your cold job but:

Should be able to pull the UIM, do the plugs, ohm the wires, replace the PCV and hose and other misc. bad vacuum hoses in an hour.

I did '01 and '03 and it is not that bad if you have the tools.

And while into it, clean the mass air sensor, clean the TB and replace the air filter. (and clean air elbows at the valve covers)

Oh well, been there done that.

-chart-
 

·
Registered
Joined
·
18 Posts
The rubber elbow that connects the metal tube coming up from the PCV valve to the underside of the throttle body deteriorates and gets a crack in it. This is a common reason for the P0171, P0174 codes. As I remember I also had the P0301 or P0303 along with the P0171, P0174. Anyhow, a new rubber elbow fixed it.
 
1 - 11 of 11 Posts
Top