Manifold Absolute Pressure Sensor

LQ1906

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I recently changed coils and plugs a few months back. Yesterday I'm driving and I get another dreaded CEL. Hook it up to a scan and I get code P0108. M.A.P. sensor. I've never heard of this before but it seems to be related to EGR valve system. I went to Ford Parts online to look for part and I can't find anything related to it. No part number of anything. What are my next steps? How expensive to R&R or do I need to focus somewhere else??? 03 Lincoln LS v8 Sport btw.

Thanks
 
The MAP sensor is in the EGR valve assembly. It can't be separated. You need 3W4Z-9D475-AC EGR valve, and you would be wise to also get 3W4Z-9E498-BA connector. This is the vacuum hose assembly that connects to the intake, EGR valve, and fuel pressure sensor. The hard plastic vacuum lines in it can just crumble apart when you go to remove the valve, due to the years of heat exposure.

A few of us now have had P0108 and it was solved by replacing the EGR. Also note that some have tried aftermarket valves and they didn't work. Get the Ford one. $110 for the valve and $36 for the vacuum hose assembly.
 
Thanks Joe

How hard is it to replace from someone who has very little experience working on cars. Is it something that is labor intensive or fairly easy to remove old and install new one.
 
Also someone mentioned that the LS doesn't have a MAP sensor but a BAP??? Stating that the BAP is part of MAF assembly and that it could be a bad connection, wiring, malfunctioning PCM, or dirty assembly......Hmmm anybody heard this one?
 
It is not too difficult. Be careful not the damage the fuel pressure sensor when you disconnect the exhaust tube from the EGR valve. Getting the connection started between the exhaust tube and the new valve is the most difficult part.

AFAIK, the LS has no BAP. It certainly does have a MAP built into the EGR assembly. The MAF measures mass air flow and intake air temperature (gen II), but not pressure. Search for P0108 and note the outcomes.
Search Results for Query: P0108 | Lincoln vs Cadillac Forums
 
Is it something that is labor intensive or fairly easy to remove old and install new one.
It's not too bad. The nut on the large pipe can be a bit "stuck",,, so you'll want to soak it with some PB Blaster,,, and let it sit for a couple hours.

Also... the gasket between the EGR and intake plenum,,, can drop out and get lost if you don't have a way to grab it. A magnet won't work because the gasket is stainless steel.

Best way is to loosen both bolts, (after loosening and unthreading the big nut on the pipe)... then pull the bolt on the side closest to the intake manifold, (left bolt). When the gasket swings down,,, you can grab it with a "plunger" type claw tool. Then pull the other bolt, (right bolt). Upon assembly... install gasket in reverse order... only with gasket pointing up, (so it pivots down to the left.

Keep the right bolt just tight enough to put some slight "drag" on the gasket,,, and push it down into place. Line it up with a smaller, (than bolt), phillips screwdriver... and install left bolt. Make sure that the pipe is lined up at this point... and thread nut on snug. Then tighten both bolts to proper torque. Then tighten big nut on pipe to proper torque.

As Joe said... watch out foor the fuel presure sensor!!! You don't want to CRUNCH that.
 
Ditto to what joegr and 04_sport_ls said! I just had the same problem and a new EGR valve cleared it up. The big fitting on the back I am sure is metric, but 1 1/16 wrench worked for me. Also, I would plan on replacing the fuel pressure sensor, I am both patient and careful and I still broke mine getting the vacuum hose off. All in all it is pretty straightforward though. Good luck!
 
So took my car in to my Lincoln dealer and they did an inspection when I got my routine Works package and so I asked them about the warranty program on the Valve cover gaskets though I know the program was for 10 years/100,000 miles. But my guy came back and said that I need the following:
Mass Airflow Sensor
Valve Cover Gaskets (left and right)
EGR Valve Assembly (MAP sensor)
Coil cover and cowl gasket
Works package (Tire rotation, oil change, and inspection)
Key Program

Parts Total: $459
Labor : $1317

GRAND TOTAL: $1811......Ouch!!!

However Lincoln is willing to offer goodwill adjustment of $800 and I pay $1000. Told them I would think about it
 
Did they have an evidence that the MAF was really bad?
You could probably skip the coil cover gaskets, they don't seem to do much anyway.
The cowl gasket is < $5.

All those things are reasonable DIY. Otherwise, this car may break you...
 
Just thought I'd drop in to support the replacement of the EGR unit correcting the P0108 & P0406 codes. I know it's well discussed here but since I just dealt with this myself on my '04 3.9L and replaced the EGR yesterday, I figured I would post up. ;)
 
Reading along. Are these some of the codes you guys got? I think I'm dealing with the same issues
IMG_1017.JPG
IMG_1020.JPG
 
Ironic that the timing of this thread coincided with a P0108 code of my own.

I managed to change out the EGR without incident. If most people are snapping off the nipple of the fuel pressure sensor/regulator,,,, it is most likely when tightening the big nut on the EGR tube.

The trick is to take "small bites" with the wrench during the final torque. Most likely you won't be able to get the wrench "square" on the nut... so mak a small partial turn,,, and "re-bite" the wrench deeper on the nut. You may have to do this several times to get a good torque on the nut.

Also... when loosening or re-tightening the nut on the tube,,, it goes faster if you invert the wrench every other turn. It doesn't hurt at the same time to cover the fuel sensor/regulator with your other hand,,, that way if you bump ithe nipple... your hand is in the way to soften/prevent a costly problem.

Yeah,,, I went against recommendation... and bought an aftermarket EGR assembly. But,,, Standard Motor Products has been around for over a half century... and I trust them. I'll report if that brand EGR has any issues.

There seem to be some subtle symptoms of the EGR failure before the P0108 code. Slightly rough idle, abnormal throttle response, (which can also cause some abnormal shifing from the trans, (both mostly in city driving. Slightly lower milage,,, and possibly a slight temperature rise of the engine... causing the cooling fan to come on in temps cooler than would be normal for it to come on. Also,,, an intermittent "jerk" or "buck" similar to a coil misfire... when at speeds of 45-55 mph.

In case the last couple statements becomes a point of contention,,, think about it. EGR starts to fail,,, and leaks a lean mix back into the combustion chambers. A lean engine will run hotter,,, and if bad enough... to the point it will misfire. Computer can compensate to a point,,, but then it gets confused due to "mixed signals" from multiple problems... which is only caused by one primary issue.
 
Ironic that the timing of this thread coincided with a P0108 code of my own.

I managed to change out the EGR without incident. If most people are snapping off the nipple of the fuel pressure sensor/regulator,,,, it is most likely when tightening the big nut on the EGR tube.

The trick is to take "small bites" with the wrench during the final torque. Most likely you won't be able to get the wrench "square" on the nut... so mak a small partial turn,,, and "re-bite" the wrench deeper on the nut. You may have to do this several times to get a good torque on the nut.

Also... when loosening or re-tightening the nut on the tube,,, it goes faster if you invert the wrench every other turn. It doesn't hurt at the same time to cover the fuel sensor/regulator with your other hand,,, that way if you bump ithe nipple... your hand is in the way to soften/prevent a costly problem.

Yeah,,, I went against recommendation... and bought an aftermarket EGR assembly. But,,, Standard Motor Products has been around for over a half century... and I trust them. I'll report if that brand EGR has any issues.

There seem to be some subtle symptoms of the EGR failure before the P0108 code. Slightly rough idle, abnormal throttle response, (which can also cause some abnormal shifing from the trans, (both mostly in city driving. Slightly lower milage,,, and possibly a slight temperature rise of the engine... causing the cooling fan to come on in temps cooler than would be normal for it to come on. Also,,, an intermittent "jerk" or "buck" similar to a coil misfire... when at speeds of 45-55 mph.

In case the last couple statements becomes a point of contention,,, think about it. EGR starts to fail,,, and leaks a lean mix back into the combustion chambers. A lean engine will run hotter,,, and if bad enough... to the point it will misfire. Computer can compensate to a point,,, but then it gets confused due to "mixed signals" from multiple problems... which is only caused by one primary issue.
 
Screenshot_20230506-182301_Torque (Lite).jpg
Getting these codes. 2006 LS. Pulled maf from another 06 that was running fine and as soon as I plug it in ar dies. Has trouble starting and wont run for long. Unplug maf and it will start and run but rough. Would egr be a second thing to check?
 
View attachment 828577705Getting these codes. 2006 LS. Pulled maf from another 06 that was running fine and as soon as I plug it in ar dies. Has trouble starting and wont run for long. Unplug maf and it will start and run but rough. Would egr be a second thing to check?
P0106 is the MAP, not the MAF. The MAP is in the EGR assembly. If all the vacuum connections to it are good, then you need to replace the EGR. Aftermarket does not seem to work for this part.
P0113 is the IAT sensor, which is in the MAF. If a known working MAF causes your car to stop running, you probably have an air/vacuum leak somewhere past the MAF in the intake.
 
P0106 code is for the MAP sensor.

In the link I posted, Joegr says that the MAP sensor is part of the EGR valve assembly.

So you will have to get a new EGR valve and replace the old one.

There are tips in one of the links (threads) that explain how to do that.
 
P0106 is the MAP, not the MAF. The MAP is in the EGR assembly. If all the vacuum connections to it are good, then you need to replace the EGR. Aftermarket does not seem to work for this part.
P0113 is the IAT sensor, which is in the MAF. If a known working MAF causes your car to stop running, you probably have an air/vacuum leak somewhere past the MAF in the intake.
Thank you. That explanation helps. Maf is good. I'll check for any vacuum leaks.
 
And I see Joegr beat me to my response.

The OEM EGR valve has been obsolete for years.

The best option for replacement... is the Standard Motor Products EGR valve.

1 caveat. The SMP EGR valve used to be made in USA. I'm not sure that it still is... so no gaurentee on how long it will last.

The link with all the pics I took was a few years back... and it seems that my EGR/MAP sensor is finally starting to fail again.
 

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