2003 NP 3.2L DiD EWL & Code 41

[campingtechaust]

G'Day Viewers!

Yep, I have the dreaded Engine Warning Light and Code 41 problem.

I have trawled through the volumes of fantastic info, tips, diagnostic tips and help the members have posted on this forum and although I am technical, I am struggling with finding key bits of info.

Here is where I am at.

EWL comes on mainly under load. Code 41 but I am apprehensive to do the self-diagnostic test as my Gregories manual says you shouldn't do it on the 3.2L DiD? I have had multiple mechanics connect a tester and get code 41 so I know that is what it is.

I have had all the Emission Control Solenoids replaced - No change
I have checked the linkages to 2 of the 3 vacuum actuators - all OK and appear to be working correctly as per various manuals etc.

I currently have a vacuum gauge connected to the EGR Valve so I can check how it is performing and have observed some interesting behavior. At idle, I have a vacuum. Under power, the vacuum drops to zero but as I drive around, the vacuum doesn't always stay at zero under light power. Not sure if that sounds normal or not?

I am also struggling to find components. My throttle body is the one show in the image.

This tells me I have an early NP (200-2002) but my vehicle was built in DEC 2003. I don't know if my vehicle has a Throttle motor and TPS or throttle position is by cable from the accelerator. I know I should be able to stick my head under the dash and see a cable or APPS if it existed but for some reason, identifying these components seems to be challenging.

I am wondering if any members out there have some experience with this particular throttle body and can help me understand what components are applicable to my vehicle and where they are?


Cheers
Jason

[MatthewP]

The accelerator pedal uses an electronic position sensor (drive by wire), to send accelerator input to the ecu.

The intake throttle valve, as per your picture, is actuated by vacuum solenoids and has no electronic position sensor in it.

The EGR valve is supposed to work as you describe.

I would try removing the filter and hose, from the intake manifold, that runs to the MAP sensor, on the fire wall, and clean them all with aerosol MAF cleaner.

If the filter, hose or sensor are dirty and partially blocked then it can cause issues with the ecu and throw Check engine lights or engine warning lights, as you called them.

There aren't many sensors on these engines, so the cause for the warning lights aren't always as obvious or straight forward to diagnose.

Next step after that would be replacing the hoses from the solenoids to the intake throttle valve.

A split in one of the hoses could stop the intake valve from activating as it should.

And of course, if you haven't aready, install an egr blanking plate.

Matt

Edit.

Welcome to the forum

[campingtechaust]

Thanks for the quick reply Matt,

I will look into the MAP sensor as you suggest.
I have been for a bit of a drive after my post and am seeing some erratic behavior from the EGR vacuum.

As you would know, the EGR has a dual solenoid arrangement. The duty solenoid is working great and I'm seeing smooth changes in vacuum level.
I'm seeing erratic behavior from the On/Off solenoid.

The On/Off solenoid should drop the vacuum under load and generally, it does this. However, if I feather the throttle very lightly, I can get the ECU to drop the EGR vacuum very quickly and for an extremely short period of time. The vacuum returns back to normal idle levels

I have previously been suspicious of the APPS and after seeing this behavior today, I'm going to test it as well as give the MAP sensor a clean.

All solenoid hoses are new and came with the new solenoid pack.
The mechanic that replaced it has two of the hoses switched around which I was able to rectify thanks to other posts on this forum.

Thanks again
Jason

[campingtechaust]

2003 NP 3.2L DiD EWL & Code 41 - Update

Hi All,

For any following this thread, I have found that the Accelerator Pedal Position Sensor (APPS) is faulty.

This is an easy device to test if you have access to an OHM Meter.
There are 8 pins - 1,2 & 3 relate to the main sensor, 4 & 5 relate to the Idle switch and 6,7 & 8 relate to the backup sensor. There are two sensors in the unit just in case one fails.

Stick your ohm meter across pins 2 & 3 and you should measure about 4.5kohm (I removed mine from the pedal assembly after marking its location on the bracket) Insitu it measures about 4.2kohm.

Sweep the white arm forward and the resistance will drop. It should drop smoothly and you should find that you have good control over the reading. Any fast jumps in the resistance spells trouble.

My main sensor had gone U/S and the backup was perfect. The ECU sets the CEL when there is a difference between the two sensors as the main and backup should always be very close to the same resistance for a given accelerator setting.

Parts? - Mitsubishi wanted $485 for a new one so that was a NOOOOOOOOOOOOO !!!!
I found one out of the US - Looked genuine as it had a Mitsubishi tag on it (right?) This was $220 plus freight but they showed 0 stock.
Wreckers wanted to sell the whole accelerator pedal assembly for $165
I got a new one off the web including freight for $200.

I'll post again when it arrives.

Haven't checked the MAP sensor yet so will post against Matt's suggestion once I get there.

Jason

[Ocean]

Thanks Jason,

Good advice on how to test the accelerator sensors.

When the new one is in and working would be good if you could share the web link where you got it from..

[campingtechaust]

MAP Sensor & Gas Filter Assembly Info

Hi All,

I've checked the MAP sensor and it was nice and clean. In my vehicle, although it is a 2003 NP, the engine build is the older style 2001.

My MAP sensor is connected to the intake manifold via a vacuum tube. The connection point to the manifold is via a device called a "Gas Filter Assembly" according to one of the Pajero manuals I have.

This Gas Filter Assembly seems to be very dirty and I want to remove it to clean it but haven't found any info regarding this.

I suspect it may need replacement so I was wondering if any forum users would know the part number and does anyone have experience in cleaning it?

Thanks
Jason

[Ocean]

Have a search on the forum, there is info on removing it and cleaning it. As yet I have not done the job but will be in over the next few weeks..

[campingtechaust]

MAP Sensor & Gas Filter Assembly Info

Hi All,

The Gas Filter Assembly is easy to remove with a 24mm long reach socket.

See pic attached. The Photo should be rotated 90 degrees clockwise. The filter is the small pinkish looking canister with the vacuum hose that sits between the engine oil dipstick and the auto trans dipstick (on an auto).
Mitsubishi have a replacement for $55 so I've ordered a new one.

Plenty of soot came out of mine and I was able to free up the airflow by blowing through from the Boost Sensor side.

I used WD40 on a cotton bud to clean out the manifold side of the filter but that doesn't fix the clogged up filter.

I also want to see how bad my intake manifold is without pulling it apart so I've just invested $10 in a cheap Endoscope off the web so I can look inside.

I will post photos once I get it.

BTW - The more I do to my vehicle in this space, the better the old girl seems to run. It's early days but I think I'm getting improved fuel economy.

Cheers
Jas

[campingtechaust]

URL for Accelerator Pedal Position Sensor

Hi Ocean,

As requested, here is the web link for the APPS.

https://www.amayama.com/en/search?q=MR578790

MR578790 is the Mitsubishi part number.

Cheers
Jason

[campingtechaust]

Diagnostic Codes for NP - Flashing CEL Method

Hi All,

I have seen that many have posted information on the process to determine if there are any Diagnostic Codes by grounding pin 1 of the Diagnostic Connector.

This is an easy process but I was worried about performing this test myself as I have the Gregories NP Manual and it specifically states NOT to do this process on a 3.8L or 3.2L model.

My NP is a 3.2L DiD so I was worried about blowing something up.

Anyway, I have found that my vehicle is an early version of the NP, even though the build date was Dec 2003. That means that the ECU behaves like a 2.8L and will give exactly the same codes.

Hopefully, this info is useful and you lot are not all going - Ummm Duh???

The upside? I can successfully get the codes out of my vehicle and now I don't have to pay my mechanic $120! BONUS!!

Moral of the story - not all 3.2L DiD NP Pajeros are the same! There are 2 different versions of the 4M41 Diesel and Engine Codes. I don't know why my vehicle has the older style engine in it for a late 2003 build. Just lucky I guess!

Cheers
Jason

[Aussie_Dan]

Anyway, I have found that my vehicle is an early version of the NP, even though the build date was Dec 2003. That means that the ECU behaves like a 2.8L and will give exactly the same codes.

What ECU on a 2.8????
The 2.8 is mechanically injected and does not use an ECU.
I wouldn't take that Gregorys manual for gospel......

[Trojan]

Also, is it still throwing Code 41?

[campingtechaust]

G'Day Dan & Troy,

Yes, I have found a few discrepancies with the Gregories manual so I get (and suspect) that there are possible errors.

Bear with me for a sec and I think you will see where my confusion is coming from.

I have attached the page with the diagnostic codes from my Gregories manual.

You will see that the 3.2L Diesel is shown to have "P" Codes. This isn't what either of my mechanics got when they connected their scan tools. They got Code 41, which according to the Gregories manual is for a 2.8L Diesel. This is where I got my reference above to
"That means that the ECU behaves like a 2.8L and will give exactly the same codes."
The codes I get are the same codes as from a 2.8L - according to the Gregories manual.
I was skeptical that this was correct as you good folk we all giving info to the contrary.

My conclusion is that as far as codes go - I'm using and have printed out the ones from this forum, complete with the transmission and transfer case codes. - All Good.

My reference to the ECU Dan may be just a terminology error. Again, if it is to be believed, the Gregories manual refers to the device that monitors and controls the vehicle's systems is the PCM/ECM (Powertrain Control Module / Engine Control Module). I assume that if the 2.8L can provide Diagnostic Codes (as per my attachment), they must be coming from a PCM/ECM?
Perhaps my ASSumption will make an ASS out of me! (won't be the last time!)

As for the code 41 - The CEL came on twice over the weekend but I had a cheap vacuum gauge connected at the time which stopped working at the same time. I expect the pressure from the turbo destroyed it and with the boost sensor loosing pressure, the ECM threw up the CEL.
Sure enough, I did the "Ground Pin 1" test last night and got the following codes:
11
12
27
41
49
All of which I can explain through my various tests on the APPS and Boost Sensor but I expect the code 12 was also generated over the weekend when the Vac gauge went. The downside of not using a proper scan tool is that you don't get to see any date/ time stamps on the codes and how many times they appear.
I removed the dead vac gauge at the time the CEL came on and haven't had a CEL since but admittedly, I haven't done too many Kms since.
Codes were cleared this morning so I just need to see how it goes.

By the way - the new Boost sensor filter was picked up and fitted today. Much improved airflow through the new one compared with the old one. At $55 from Mitsi, I think it is worth changing out periodically. My NP has 360,000 on the clock.

Thanks for the posts Fellas. Questions, comments and occasional scoffs all welcome! Very impressed with your posts Dan. It was your info that prompted me to join so cheers mate!

Jason

[campingtechaust]

Sorry, attachment didn't load for some reason.

You are probably wondering why I had a Vac Gauge attached to the Boost sensor? Before I realized the Inlet manifold would get to around +18 - 20 PSI from the turbo, I was reading about MAP sensors and that the inlet manifold would have a vacuum under de-acceleration.
The rest was history but history won't be repeating itself in this case!

Jason

[MatthewP]

The headings on the attachment are wrong.

The codes under the label for the 2.8 engine are for the pre commonrail 3.2 DID.

The codes under 3.2 are for the commonrail 3.2 engine.

Matt