1990 940 GLE 16V Automatic ~93,000 Miles Various issues

[girlbunny]

I did the Fuel System Diagnostics and it came up with one error 1-2-1 Mass Airflow Signal. Since I'm sure you were the one that supplied the fault codes tables, I suspect you may already know that it suggests to check airflow meter (which is something the mechanic brought up) and to check 02 Heater Resistance.

How hard are these to do/check?

[billofdurham]

Perhaps the garage isn't so iffy after all.

Sometimes the Mass Airflow Meter (MAF) can do with a clean. It is, in theory, self cleaning but occasionally it benefits from a squirt of MAF cleaner which you should be able to buy at any good parts shop for a modest sum of money.

To test the MAF you need to get out your multimeter.
1. Ignition 'Off' and disconnect the connector from the MAF. You will see this:

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2. Set multimeter (MM) to ohms and connect between socket 1 and earth (ground). It should read 0 ohms.
3. Ignition 'On'. Set MM to volts and connect between 5 and earth. It should read battery voltage.
4. Ignition 'Off'. Connect the connector to the MAF. Ignition 'On'. Back probe into 3 and earth. Voltage should read 1.4 volts.

If any of the readings are incorrect check for bad wiring and oxidation.

The oxygen sensor resistance is measured by connecting the ohmmeter between the sensor harness terminal #2 (black wire) and earth. This is located next to the bulkhead (firewall). A cold oxygen sensor should read 2 - 3 ohms. A sensor that is warmer than 660F (350C) should read 7 - 14 ohms.

I would spray the MAF first as it has 'repaired' many cars in the past. If you still have the problems do the checks.

Bill.

[girlbunny]

Thanks Bill.

I'll now have to find a way to the parts place, because last night, she died totally. She'll turn over, but refuse to keep going.

I've been searching for replacement Air flow meters, but the cheapest I can find is in the UK at 60 pounds including shipping.

If I can get her going with doing this, it will solve so much stress it's not funny!

[girlbunny]

Okay, now I know I'm a moron... I just took my multimeter to try to do tests. Couldn't get a single reading because I had no idea where the earth is. What should I be using for earth? I was presuming number 6, since the others were used for other things, but no luck in getting any readings.

My multimeter has volts, amps and ohms. I tried the ohms section first (obviously, since that's where you asked me to start!) however, there are multiple settings to put it on in each section. The ohms section goes up in steps from 200, 2k, 20k, 20k, 2M - I'm presuming that I'd need to set it on 200, since that's the lowest (and presumable most sensitive) setting? Secondly, I have certain things I never remember, no matter how many times I'm told them... and one of those is which 'wire' I should be using for the pin listed, and which for the ground. I have a red cable, and a black one. I'm presuming red goes into pin 1, and the black goes into the ground??

Any suggestions would be appreciated, since I'm really feeling... well... ultra female right now LOL

Well... that, and I don't really like having to be towed home last night Poor kids stuck waiting for the towie for quite a while before I managed to secure a ride to get them home to bed!

[billofdurham]

Earth or ground is any part of the metal frame of the car, preferably with no paint on it. Testing the MAF you are very close to the battery so use the negative post of that. For total safety with a multimeter it is best to start with the higher settings and work down if necessary, especially when testing AC voltage. You will get the same readings on the higher scale but lower down will make it more accurate by dropping it to decimal.

Which wire goes where? Red is positive, black negative. However, using it as an ohmmeter it doesn't matter which you put on what. Using a digital multimeter as a voltmeter if you put the probes to the wrong side you won't hurt the meter, it will simply put a '-' sign in front of the reading. An analogue meter simply moves the needle backwards and gives no reading.

Believe me this isn't 'an ultra female' thing. My son always gets a negative reading first time.

Bill.

[girlbunny]

Thanks

The MAF is on the opposite side of the engine bay of the battery, so can't really reach the battery. Having said which, there are multiple metal parts of the car to ground on, so I can do that easily enough

I caught a cab and grabbed some MAF Cleaner from the local auto parts place. Currently it's in the drying out time frame, so I have to wait to see if it works. If not, I'll probably order a new one from eBay in the UK - 60 pounds including shipping compared to the enxt cheapest of 200 USD plus shipping is too big a difference to toss up right now.

[cattledog]

An easy way to see if the mass air flow sensor is bad, unplug it and try and start the car, if it starts right up when it wouldn't start at all before, good bet it's bad. Don't drive it that way, it doesn't respond well!
Sounds like you're enjoying that car, even with it's issues.

[girlbunny]

Okay, she started on her own.

Once.

I decided to try and see if she'd idle low again, and well... she did. To the point of stalling very quickly... and then wouldn't restart.

I went back an hour later to see if I could start her again, and ALMOST got her started, but once she had died, she refused to try again.

Note: Because I was trying on my own, I was NOT trying with Aerostart. Just the fact that she'd start without it at all is promising... but there's obviously a few issues.

I checked the OBD again, it still gives the 1-2-1 code... It briefly then gave me a 3-1-1 code, and once gave me a 1-2-2 (I think) code. I haven't been able to get it to give me further codes again, so guess I did something right the first time, and have been doing it wrong ever since. 3-1-1 told me something I've known fora while... the speedo is on the fritz. Well *duh* I've essentially had no reliable speedo for over a year, I'd already figured there was an issue Any ideas on how I got the extra codes the once but not since?

[girlbunny]

Okay, I figured out how I got it to spit out more codes.

Considering she only holds three codes, it's rather ominous that there are three different codes there.

First is the 1-2-1 Mass Airflow Signal.

Second is 2-2-1 Lamba Operation

Third, which I *thought* I remembered as 3-1-1 was *actually* 1-3-1 Ignotion System RPM Signal.

So... just what am I facing here? Honestly. I have extremely limited funds, and I'm less than a month away from being homeless (received an eviction notice on Christmas Eve, of all times, since the owner wants to sell) Just the Mass Airflow Meter is enough to drive my budget into palpitations, in fact, the MAF spray was pushing it, let alone the part itself. *IF* these things are the only things that are wrong on the car, what kind of monetary hit am I potentially facing? I already figure I'll need to look for handbrake shoes... but the rest is just plain scary right now.

Are there any Volvo people in south east Queensland who are able to help? I need to get her re-registered within the month, and at the price, it would be cheaper to put that money toward a replacement, if all of this is going to be too expensive. She's a good car, she obviously had a really rough life before I got her... but this is looking like it's going to be too much for me to handle.

What do you guys think? Am I pushing excrement uphill at the moment, or is there a chance I can get this old girl running?

[girlbunny]

I had an epiphany!

I cleared the OBD units memory. I have this minor fear of screwing with the battery (I have been electrocuted in the past, courtesy of my opor fathers "skills" with electricity!) however, I used common sense, so all was good

Anyway, I no longer have 3 error codes coming up, with the fear of more lying in the wings. I have TWO error codes coming up, one is different from the previous three, and two of the previous three have disappeared.

I am left with:

2-3-2 Lamba Adjustment
2-2-1 Lamba Operation

Both of these suggest to check the intake manifold and fuel pressure.

I'm presuming that the air mass sensor is no longer an issue, since the OBD no longer sees it as a problem. I do still have a problem with starting her. I needed to use aerostart to get her going, and had to keep my foot lightly on the accelerator in order to keep her revs high enough to keep running.

However, because I only had to put my foot lightly on the accelerator to keep her running, I'm figuring I can try to up the revs so I can take my foot off the accelerator whilst at a stop.

So... now that I've pulled my head into line and I'm no longer terrified that getting her up and running will cost an arm, a leg, and my firstborn son... what do I need to do in order to check the intake manifold, and how can I check the fuel pressure? What may need to be fixed in order to fix this issue, and how hard would it be for me to do on my own? If I need to get under the car, she'll need a mechanic, but if I can do it from above, I *think* I can manage it.

The one thing that playing with the MAF has done for me is to really up my confidence level that I *can* do a few things on the car without it costing a heap, and that I can fix something without actually... well... breaking it.