PO174 and PO171 codes, 2000 Mercury Sable

Page 2 of 3  


Was common on the 2.5 in the Contour/Mystique in 1996-97. I thought they had fixed it on the '99 and up 3.0 in the Taurus but it is definitely worth a check. I did have that problem on our old '96 Mystique - chased that lean condition for weeks. It only went lean on decel - high vacuum collapsed the hose, opening the crack. Roughly half inch hose coming off the bottom of the throttle body on the mystique - and in 2002 it was already discontinued from Ford and was a "dealer only" part. I found a moulded heater hose at Napa that fit by cutting a bit off.
That's why I asked what engine, becuase the Essex and the Duratech are too totally different animals and we don't want to be giving solutions for the wrong engine.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 01/05/2015 05:14 PM, snipped-for-privacy@snyder.on.ca wrote:

Forgive the maybe elementary question, but what's the best way to find out which engine I have?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 1/5/2015 5:34 PM, Sam Seagate wrote:

Eight digit of vin code
http://www.ford-taurus.org/taurusinfo/Engine/VIN8.php
bob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 05 Jan 2015 18:34:21 -0500, Sam Seagate

Google and look at the pictures. The Essex/Vulcan pushrod engine has narrow valve covers and is lost under that big hood. The Duratec has WIDE covers and fills the hood. The plugs on the essex/Vulcan come out the side of the heads and are visible. You almost need to be houdini to find the plugs on a duratec. On some cars with the duratec there is a "32 valve" emblem on the fender.
Or just check the 8th digit of the VIN code. 3: 3.0 (OHV) Essex U: 3.0 (OHV) Vulcan S: 3.0 (DOHC)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 01/05/2015 08:45 PM, snipped-for-privacy@snyder.on.ca wrote:

Ok, 8th digit is a U, so 3.0 OHV Vulcan

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 01/05/2015 09:08 PM, Sam Seagate wrote:

Alright, yesterday I cleared the codes, let the car sit overnight, and did the drive cycle this morning as described here:
http://repairpal.com/how-to-perform-a-basic-drive-cycle
Afterwards, I hooked up the scanner and went into the "readiness" screen. Here is the printout:
Since DTCs cleared MIL() OFF MIS() OK FUEL() OK CCM() OK CAT() INC HCAT() N/A EVAP() INC AIR() N/A O2S() OK HTR() OK EGR() OK
IIRC, it seems that not everything was tested... CAT and EVAP ring a bell and the yellow caution light was illuminated on the scanner.
Not sure what this means. So far, no return of the check engine light on the dash.
I did not do any data checks yet like I did yesterday, just the I/M readiness test.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

All monitors are complete and ready, except the Evap and the CAT. It is common that these are the last to complete.
Just because you drove a qualified drive cycle does not mean that the monitors will clear/complete. If they detect any abnormality in the data they monitor then they can take an additional drive cycle, or two or three or more.
EVAP is the system that collects gasoline fumes and returns them to the fuel tank to begin the journey anew. Evaporative emissions are emissions that occur before combustion, basically raw fuel escapes to the atmosphere. These emissions are captured and returned to the fuel supply -- there are various ways to accomplish this, different car makers will use different methods -- and you are waiting for the system to be sure all compoinents within it have strong integrity. This system is not directly related to the codes you asked about, that is this system will not cause a LEAN condition.
CAT is the exhaust emissions, or catalytic converter. The exhaust emissions look at the exhaust going into the CAT and the exhaust coming out. The exhaust going in is analyzed for air/fuel ratio and the computer uses the results along with the input from the MAF to set the fuel injector timing. The data from these sensors is a direct feed to the codes you have, although not necessarily the cause of the codes that you have. You can have a false LEAN, in which case the sensors are failing. Or you can have a true LEAN, in which case you have something to fix. There are sensors before and after the CAT, your issue comes from information collected by the sensors before the CAT.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 6 Jan 2015 09:08:42 -0800, "Jeff Strickland"

Inless there is a leak in the system on the manifold side of the sensors - but USUALLY that will also set an evap code.

A failing O2 sensor on a Ford will almost invariably give a cat failure or O2Sensor failure code, not a lean engine code - and the chance of both banks failing at the same time is EXTREMELY slim. The problem is most likely caused by something common to both banks. That is MAS sensor, Fuel quality, or main plenum air leak (including anything the taps into the main plenum or throttle body)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 06 Jan 2015 07:23:50 -0500, Sam Seagate

The evap won't set if the tank is too full or too empty, or the temperature is not within range.. The cat might not set untill the second or third cold start cycle. Light being off is a "good thing"
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 05 Jan 2015 21:08:26 -0500, Sam Seagate

That simplifies things then - at least on that engine it is POSSIBLE to see and reach just about everything of importance. The S code Duratec is packed in pretty tight!!!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Ok, I decided to reconnect the scanner and had it record data at both idle (~700 RPM) and 2500+ RPM. Here is what it recorded:
Live Data Number of DTCs stored in this ECU 0 Fuel system 1 statusCL Fuel System 2 status-- Calculated LOAD Value(%)27.1 Engine Coolant Temperature(¡£C)87 Short Term Fuel Trim -Bank 1(%)15.6 Long Term Fuel Trim - Bank 1(%)25.0 Short Term Fuel Trim -Bank 2(%)12.5 Long Term Fuel Trim - Bank 2(%)25.0 Fuel Rail Pressure(gauge)(kPa)270 Engine RPM(rpm) 698 Vehicle Speed Sensor(km/h)0 Ignition Timing Advanece for #1 Cylinder(¡£)26.5 Intake Air Temperature(¡£C)6 Air Flow Rate from Mass Air Flow(g/s)2.74 Absolute Throttle Position(%)18.8 Location of Oxygen SensorsB1S12--B2S12-- Oxygen Sensor Output Voltage Bank 1-Sensor 1(V)0.660 Short Term Fuel Trim Bank 1-Sensor 1(%)13.3 Oxygen Sensor Output Voltage Bank 1-Sensor 2(V)0.840 Short Term Fuel Trim Bank 1-Sensor 2(%)N/A Oxygen Sensor Output Voltage Bank 2-Sensor 1(V)0.065 Short Term Fuel Trim Bank 2-Sensor 1(%)16.4 Oxygen Sensor Output Voltage Bank 2-Sensor 2(V)0.835 Short Term Fuel Trim Bank 2-Sensor 2(%)99.2 OBD requirements to which vehicle is designedOBDII
Number of DTCs stored in this ECU 0 Fuel system 1 statusCL Fuel System 2 status-- Calculated LOAD Value(%)22.7 Engine Coolant Temperature(¡£C)85 Short Term Fuel Trim -Bank 1(%)5.5 Long Term Fuel Trim - Bank 1(%)5.5 Short Term Fuel Trim -Bank 2(%)5.5 Long Term Fuel Trim - Bank 2(%)7.8 Fuel Rail Pressure(gauge)(kPa)270 Engine RPM(rpm) 2753 Vehicle Speed Sensor(km/h)0 Ignition Timing Advanece for #1 Cylinder(¡£)47.5 Intake Air Temperature(¡£C)6 Air Flow Rate from Mass Air Flow(g/s)13.78 Absolute Throttle Position(%)27.1 Location of Oxygen SensorsB1S12--B2S12-- Oxygen Sensor Output Voltage Bank 1-Sensor 1(V)0.720 Short Term Fuel Trim Bank 1-Sensor 1(%)0.8 Oxygen Sensor Output Voltage Bank 1-Sensor 2(V)0.775 Short Term Fuel Trim Bank 1-Sensor 2(%)N/A Oxygen Sensor Output Voltage Bank 2-Sensor 1(V)0.565 Short Term Fuel Trim Bank 2-Sensor 1(%)0.0 Oxygen Sensor Output Voltage Bank 2-Sensor 2(V)0.750 Short Term Fuel Trim Bank 2-Sensor 2(%)99.2 OBD requirements to which vehicle is designedOBDII
From what I see, the fuel trims sharply drop which, according to some information I've come across, indicates a vacuum leak. Since the fuel pressure values seem to appear the same (270 kPa), I don't think the fuel filter or pump are concerns here. What is the consensus? I think it may be time for a smoke test since I have been unable to find anything with propane or carb spray tests.
Something interesting also occurred. When I re-ran the readiness check, it of course came up with the CAT and EVAP not yet ready, but a pending code is PO300. This is the first time anything like that has been pending, only the 171/74 were designated before when I cleared them.
I think the lights will be coming back on once the tests are complete, unfortunately.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

P0300 is a multiple cylinder random misfire. It can be the result of the lean condition. So, we are back to Day 1, you have a vacuum leak somewhere. Air that has not passed through the MAF is getting into the engine (intake) somewhere.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 6 Jan 2015 16:06:30 -0800, "Jeff Strickland"

OK - 3 common problems on 3 liter 2000 Vulcan engines. Check the vacuum line on the FPR (Fuel Pressure Regulator). If it comes right off the engine can go rich, but a minor air leak can make it go lean AT IDLE. It will have little or no effect at speed.
The connection on the EGR Vacuum line is also a common leak on that engine, both where the hard plastic line connects to the rubber elbow.
They also have intake manifold problems. Disconnect the plug from the ISC (Idle Speed Control) valve to do vacuum checks with propane or ether. Leaving it connected you can not detect the leak because the ISC compensates for any change in idle speed.Check between upper and lower intake manifollds
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 01/06/2015 11:10 PM, snipped-for-privacy@snyder.on.ca wrote:

Do you know of anywhere I can find diagrams/schematics for the locations of these items? I'm still pretty much working in the dark not having much luck finding the info. When I google it, I am coming up with other years models so not sure if they apply or not (Duratech and such).
It's so cold here that I am going to only be able to try out these things once or twice, so I want to be sure and do it correctly. I did find info on the FPR.... is the hose on the top or bottom of it and how would I know whether or not the line is bad?
Are these items reachable without ramps?
Thanks, Sam
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 07 Jan 2015 06:37:56 -0500, Sam Seagate

All are reachable without ramps. Look at the ends of the tiny hard plastic hoses - they have rubber "elbows" on them, or possibly just rubber hoses about an inch long. They crack and split. The hoses you are interested in there are less than 1/4" diameter and fit on little nipples sticking out of the vacuum actuator cans.
A smoke test is the most effective way of locating them, but we mechanics have been locating and fixing vacuum leaks without smoke testers for over 80 years - close to 50 for myself.
I'm looking at getting myself a smoke tester to make it easier on the more complex engines. Yours is simple as a sack of rocks compared to most!!!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 01/07/2015 07:25 AM, snipped-for-privacy@snyder.on.ca wrote:

I made a smoke tester yesterday and it only took a minute to reveal the problem-- the leak is somewhere under I think what is called the intake manifold (the piece the throttle body is attached to). Smoke came from nowhere else other than there. Now the issue is whether or not I have to remove this entire assembly as it looks like it and the throttle body are attached. I have plenty of questions to how to go about it if so, but at least I now see where the leak is coming from. If I can now get the leak remedied, I'll share at some point how I made the smoker.... about $30 using parts from Walmart.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 1/8/2015 8:29 AM, Sam Seagate wrote:

If you have the plastic dual plenum intake, there have been some incidents of holes in the plastic. So it might not be a hose, but the intake itself. It will have to come off and closely inspected.
bob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 01/10/2015 05:16 PM, bob wrote:

Luckily, it's I believe aluminum and not plastic. I am making progress removing the manifold, but slowly. With some help, I was able to find a video of the process for this particular engine, which is the Vulcan 3.0 OHV. There are a couple of things that I missed that are still bolted on.... EGR and there is a bolted strap between the manifold and engine.
I can lift the manifold just far enough off to see the gasket underneath. I'm not totally clear from the video exactly what would need replacing once I have the manifold off.... I assume this gasket needs replaced, but the video talks about "seals" so not sure what the difference is. I also wonder if the gasket needs greased in any way.
One good thing I've spotted is that the PCV value I keep reading about on these engines seems to be in good shape. If it ever fails, I believe I can replace it without removing the manifold.
Sam
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 06 Jan 2015 17:06:51 -0500, Sam Seagate

Random Misfire.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 4 Jan 2015 16:22:52 -0800, "Jeff Strickland"

Without ANY high-tech equipment or data-mining he can eliminate fuel quality (a COMMON cause of the codes on that particular car) - and he can check the hoses more carefully if that doesn't solve the problem. He needs a simple code scanner to read the codes and shut off the light. If he has an air leak, he can look first at anything that would affect both banks equally.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.