Jambo to Everyone!!

Good Day Everyone,

Hope we are all doing well.

My name is Mike from Kenya , East Africa. I own a 1997 Galant Vr4 with an auto gearbox. Its been a journey owning this car, been through the good and bad but i still love the car.

I kindly need advise from the good folks in this forum regarding the Vr4's air flow sensor. I have been forced to park the car for a period of about 1 month due to a malfunctioned maf sensor, getting a replacement has been harder than expected.

My question is therefore, can i use a maf sensor from a different mitsubishi model without losing any power or facing any other issues?

Cheers,

Mike


Attachment 80132

Welcome to the club.

The MAF is exclusive to the VR4 so one from another vehicle probably won't work. The Mitsubishi part number is MD334005 - SENSOR, AIR CLEANER AIR FLOW

Someone on here may have a spare that they are willing to sell.
:happy:

/Welcome

As far as I know Tim is right. £500ish new and now discontinued I believe.

/Wave

Hopefully, someone will be able to provide you with a MAF! :seeking: /yes

Hi Mike,

Are you certain it's definitely the MAF at fault? Are you happy to do a little extra troubleshooting before someone sends you something?

If you unplug it, does the issue disappear and does it drive a little better?


I've got a MAF, which I'll happily sell you :) Postage will be the main killer cost, but it'll still be cheaper than a new one! But, I'd rather be sure that it's the MAF at fault than have you pay out all the costs to get hold of another MAF and find you're still left with the same outcome!


Garry

Quote:

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Originally Posted by Confused

Hi Mike,

Are you certain it's definitely the MAF at fault? Are you happy to do a little extra troubleshooting before someone sends you something?

If you unplug it, does the issue disappear and does it drive a little better?


I've got a MAF, which I'll happily sell you :) Postage will be the main killer cost, but it'll still be cheaper than a new one! But, I'd rather be sure that it's the MAF at fault than have you pay out all the costs to get hold of another MAF and find you're still left with the same outcome!


Garry

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Hey Garry,

I actually had an extra Maf that came out of an outlander so i fit it to the VR4, the car idles perfectly with it, only issues are that the car has become very thirsty and the power output has reduced significantly.

Attachment 80133

If you were to sell your maf how much would it go for + postage? I got an offer earlier today from one of our local shops which is selling a second hand VR4 maf for about 110 dollars, so i am thinking of going to pick it up tomorrow morning.

Thanks

Mike

Looking briefly at a few options for postage earlier, they were coming out at about £50. I'd not want much for the MAF itself, so say £75 posted :)

If you can source one locally tomorrow and its works, I'd consider that option than leave a parcel in the hands of courier services! ;)

I decided to buy the local one and the car is performing well. going for a run today to see how the car fairs.

Cheers and thank you.

Darn, if I'd seen this thread earlier I could have told you how to (almost certainly) fix your original one.

Quote:

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Originally Posted by Tony_T

Darn, if I'd seen this thread earlier I could have told you how to (almost certainly) fix your original one.

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There are plenty going wrong, the info will still be useful to some. /yes

Hi Jambo.
BTW I had a lady friend for a while in Nairobi; sweet lady but what a scrounge so I finally told her that I'd contributed as much to her life as I was prepared to and to look elsewhere. Pity, really hoped one day to bring her to NZ.
Anyway that's off topic. I'm an electronics tech, I've spent my life doing component-level repairs to a wide range of electronic devices so when my green Legnum played up and I traced it to the MAF I naturally decided to pull it apart and see what went wrong with it. I traced out the circuit diagram and set it up on my workbench to look for the fault, it turned out to be easily found and also easily fixed. I'm not saying for certain that this will be the fault with yours, but I'd just about put money on it!
Here below is a copy of the post I made on the Australian VR4 forum to help folks there:

The hardest part of the repair is getting the top lid off without breaking any of the four little plastic tabs which hold it on. In my case it seemed that there could have been a bit of silicone sealant also keeping the lid on which made it harder so I ended up breaking two of the tabs and having to improvise some clips to take their place. So, remove the MAF from the car and if you like, dismantle it from the plastic airway parts to make it easier to handle. Then remove the lid. Under the lid you'll see a metal shield which is held in place by springy tabs. Just ease the shield out, try not to bend it so it will fit back nicely later.
NOTE: the purpose of the shield is to prevent any radio frequency signals nearby from affecting the operation of the MAF. Test at idle with it removed but DO NOT take the car onto the road without it in place: I do not accept responsibility for any crashes caused by sudden changes to the car's operation while driving due to some nearby radio emission e.g. your cellphone!!!!!
Our MAF works by the incoming air which has had turbulence caused by the special inlet and shaping passing over two heated wires causing their temperature to vary. As with most metals the electrical resistance of these wires is temperature dependent so we have a variation of resistance in response to the airflow. To allow this resistance change to be measured accurately the current which flows through the wires to heat them must be carefully regulated. This is accomplished by having a precision resistor in series with each wire, the voltage which appears across this resistor is compared with a reference voltage in some simple electronics and the resulting error signal is used as feedback to the current control transistors. This means that when the car is switched on these resistors also heat slightly due to the current flowing through them, and when the car is switched off again they cool. As with most things they expand and contract slightly with this heating and cooling. They are soldered to copper tracks on a fibreglass based circuit board which has a different amount of thermal variation and this causes stress to be applied to the solder joints at each end of these resistors, eventually causing the solder to crystallize and become an intermittent connection which is very susceptible to vibration. In my case the car would often idle but when any throttle was applied the vibration caused the contact to make and break rapidly giving extra pulses from the MAF to the ECU. The ECU saw this as heaps more airflow and ramped up the fuel to the point where the mixture would not ignite stopping the engine and producing rather a lot of black smoke occasionally.
The repair:
I'm assuming you or someone you'll get to do this for you is confident with soldering of electronic components:
Locate the two larger resistors which are flat rectangular items on the circuit board towards the top right of the board if the socket which connects to the car loom is on your left. Mine had the value 6R2 written on them, I expect all MAF's will have the same value resistors, it could be written 6E2 by some manufacturers. Using a small soldering iron somewhere around 30 to 50 watts power and preferably temperature controlled carefully melt the solder on both ends of one resistor and lift it away from the PC board. A pair of fine tweezers may be helpful but don't damage the resistor. You may have to keep heating the ends alternately a few times to get it off (don't force it) unless you have one of the special soldering tools which heats both ends at once.
Don't do both resistors at once as all resistors have some production spread of actual resistance and this has been accurately compensated for at the factory (you'll see some tubular resistors on stand-off legs which have been chosen for exact calibration) so you don't want to mix them up.
Once it is removed, use the iron and some fresh electronics grade resin cored solder (preferably 60/40 leaded not lead-free as it cracks too easily) to reflow and clean the lands on the PCB where the resistor attaches. Then do likewise with the terminations on the actual resistor. When fully satisfied that all is clean and good to go, solder one end of the resistor back onto the PCB, leaving the resistor sticking up at a small angle so the other end is clear of its land on the board (if you're not too familiar with these things, they're not directional so can face either way). Now take a piece of scrap automotive electrical wire and strip it down to get some fairly thin single strands of copper and cut a strand about 5 or 6 mm long. Solder one end of this flat to the free land on the PCB and then curve the other end around to meet the resistor end flat-on. Now solder it. This provides a bit of 'give' by movement of the wire for the expansion and contraction so should help to prevent the problem from happening again. (I didn't do this when I fixed mine, I just soldered them back as they had been on the board and thought of this idea later so I will do it sometime).
Repeat for the second resistor.
Don't be tempted to just reflow the solder on the resistors in place: you won't get to the solder under them and it will be a very short term fix if it fixes it at all.
When you're happy that everything is connected correctly (it's possibly worth gently pulling on the curved wires to be sure they're really soldered properly) then refit the MAF to the car and test with the car stationary and tapping on the circuit board (not too hard that you break something though) with something insulating like a plastic pen to see that there's no change in engine operation at higher revs due to some other problem. All going well, fit the shield in place and go for a test drive (it won't pop out if you got it out without bending the metal fingers). If it passes the drive test then refit the plastic cover, putting some silicone sealant on if you wish (that may also hold it OK if you broke some tabs!) but use neutral cure silicone not RTV as RTV has an acid solvent which will corrode electronics.

I hope that can be of some help, and if there's some way it can be copied and placed into one of the info threads that would be OK with me, I can't do it as I don't have access to any of those threads.

Fantastic info, thank you!

You're very welcome Nick. Are you able to copy that to one of the general info threads where it can be readily found by anyone, as opposed to being buried away here out of general sight?