BTW, I had again to move up a few ohms... Now at 510 ohms
MAF setting Questions
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- Melvin480
- Knows where Volvo is from
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Today I tried setting the MAF using this procedure. Tried before but the LED stayed off all the time. But, lambdasensor was broken so after replacing that I had to give it another try.
From 200ohm to almost 900ohm the LED is off. Tried with a multimeter and it reads 0,99V between the battery positive and the testpoint. It never changes, no matter what the MAF is set at. Also when I disconnect the MAF (the mixture should go rich like said in this topic before) nothing happens.
I like to set my MAF at some good value. When I first measured it, it was set at 106ohm by the previous owner. Increasing this to 382ohm made idle smoother and the engine running better. The lumpy feeling when idling had become much less, but it isn't fully away jet. So I guess the MAF should be somewhat higher, but I can't measure when it is set correctly. Maybe I should just try some values...?
My car is a '89 turbo. For some reason I don't have a grey loom like in the picture on page one. My loom is black. Maybe that is the reason it doesn't work
From 200ohm to almost 900ohm the LED is off. Tried with a multimeter and it reads 0,99V between the battery positive and the testpoint. It never changes, no matter what the MAF is set at. Also when I disconnect the MAF (the mixture should go rich like said in this topic before) nothing happens.
I like to set my MAF at some good value. When I first measured it, it was set at 106ohm by the previous owner. Increasing this to 382ohm made idle smoother and the engine running better. The lumpy feeling when idling had become much less, but it isn't fully away jet. So I guess the MAF should be somewhat higher, but I can't measure when it is set correctly. Maybe I should just try some values...?
My car is a '89 turbo. For some reason I don't have a grey loom like in the picture on page one. My loom is black. Maybe that is the reason it doesn't work
- Paul240480
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Okay, Mr Novice here!
Can someone kindly give me 'idiots-guide' style
instructions on how to set the MAF.
I have a multi-tester & know about the adjusting screw on the MAF. What I do not know is which pins to connect the tester to. I did try following instructions given previously but failed to get anything other than 0.004 as a reading
Obviously I was gertting something wrong.
My mleage is at 27.2 & reckon iy should be a little higher?
Thanks in advance.
Can someone kindly give me 'idiots-guide' style
I have a multi-tester & know about the adjusting screw on the MAF. What I do not know is which pins to connect the tester to. I did try following instructions given previously but failed to get anything other than 0.004 as a reading
My mleage is at 27.2 & reckon iy should be a little higher?
Thanks in advance.
- Paul240480
- Knows where Volvo is from
- Posts: 154
- Joined: Tue Feb 13, 2007 12:38 pm
- Location: Morbihan, France
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- Paul240480
- Knows where Volvo is from
- Posts: 154
- Joined: Tue Feb 13, 2007 12:38 pm
- Location: Morbihan, France
- Contact:
Can't really help your questions GTImk1, due to me being a complete novice!
For all its worth, mine is a 91' Turbo. I reset my MAF on Sunday. Used a multi tester. Engine running and well warmed up, unplugged the connector on the MAF then connected tester to the first & last terminal on the MAF. Then turned the screw till the tester showed 382 Ohms, which I beleive is 'the norm'.
Mine was down at 280 odd, so I'm hoping for improvement in performance - early days yet.
I worked this 'method' out from my understanding of this thread - not sure if I've done it right or not.
Also I may be wrong but I think MAF sensors are specific to Turbo models - but stand to be corrected. No doubt, on here someone will confirm either way.
As for that wire mentioned earlier in this thread to put an LED tester on, I cannot find it on mine for love nor money? Mind you I have'nt got an LED tester & don't really know what one is either
Thanks to all for the posts on this one so far.
For all its worth, mine is a 91' Turbo. I reset my MAF on Sunday. Used a multi tester. Engine running and well warmed up, unplugged the connector on the MAF then connected tester to the first & last terminal on the MAF. Then turned the screw till the tester showed 382 Ohms, which I beleive is 'the norm'.
Mine was down at 280 odd, so I'm hoping for improvement in performance - early days yet.
I worked this 'method' out from my understanding of this thread - not sure if I've done it right or not.
Also I may be wrong but I think MAF sensors are specific to Turbo models - but stand to be corrected. No doubt, on here someone will confirm either way.
As for that wire mentioned earlier in this thread to put an LED tester on, I cannot find it on mine for love nor money? Mind you I have'nt got an LED tester & don't really know what one is either
Thanks to all for the posts on this one so far.
Re: MAF setting Questions
Hi, I've been reading the thread carefully, but there are some things I'm not clear on:
How do you take a lambda measurement if the car doesn't have a catalytic converter and therefore doesn't have a lambda sensor?
Where exactly do you connect the LED?
What type of LED?
Thanks!
How do you take a lambda measurement if the car doesn't have a catalytic converter and therefore doesn't have a lambda sensor?
Where exactly do you connect the LED?
What type of LED?
Thanks!
- Jay-Kay-Em
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Re: MAF setting Questions
If the car doesn't have lambda or a cat then it's even easier..... Get the car warm, take it to an MoT centre and adjust the AFM "live" on the gas analyser. You don't need multi-meters, LED's, pins or probes. Just adjust the AFM, one tweak at a time with the car running and gas probe stuck up its derrière (allowing time for each adjustment to reach the tailpipe). With non-cat cars you are looking at 1- 2% CO and no more than 300 HC.Carba1984 wrote: ↑Fri Nov 14, 2025 6:49 pmHi, I've been reading the thread carefully, but there are some things I'm not clear on:
How do you take a lambda measurement if the car doesn't have a catalytic converter and therefore doesn't have a lambda sensor?
Where exactly do you connect the LED?
What type of LED?
Thanks!
In theory with a lambda controlled car you shouldn't need to adjust the AFM as the Lambda sensor means the ECU can calculate "fuel trim" and richen / lean out as required. With a cat if you are adjusting the AFM you may be trying to hide other faults that exist. I would still recommend making a de-cat pipe and seeing what the CO is on a four gas analyser.
With OBD cars it is much easier (ours aren't) but you can still test a Lambda Sensor is producing a nice rich/lean alternating output above and below the ideal 14.7:1 AF ratio.
Jay-Kay-Em
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Re: MAF setting Questions
Can someone please make a guide for fools to adjust the CO with LED? I have a turbo without a catalyst, thank you!
