240DL 1990. Replaced both fuel pumps and flitter, fuel pressure regulator, Fuel relay, control module for injectors, ECU#951, Crank sensor(white Banded now)
and still after driving it and getting it up to temp it will bog down as I throttle up and hesitate while in the limp mode and finally stall out.

I have been keeping an eye on the diagnostic codes as each time this happens. Tonight I got a 121 and a 214 code. The 121 says that I have lost the air mass meter signal and the ignition diag. code again says I have a speed sensor signal missing or sender faulty. What is the speed sensor? (Crank Sensor)?? alreay replaced.

When it says I have lost the signal does that mean I have a bad part or does it mean I have a wire problem? Also how do I test the air mass meter..

The other thing I have been noticing is how hot the engine seems to be getting just after it looses power and bogs until stalling. The gauge shows a placement right between hot and cold but I am wondering if that is a faulty reading from a bad temp sender.

I know am getting close to fixing this so could you help me out with more thoughts please?

thanks
Judd

An air mass meter "generally" messes up when cold, not when warm, UNLESS you still have your preheat hose hooked up to your air filter box and your air filter box thermostat has failed. You have a funky looking, looks like it belongs in your home duct work instead of your car, hose that runs from your exhaust manifold around to your air filter box. This is to prevent icing up in northern climates, and aids in a quicker warm up period of your car. The problem with that is the air filter box thermostat. When it reaches a certain temp, the air filter box thermostat opens a fresh air vent, and the now too hot air is released under your car instead of through your rather expensive air mass meter. If this part fails, the too hot air now goes through your air mass meter. Try unhooking that ductwork style hose and see if it helps. Hopefully the air mass meter hasn't been cooked.

Next, check your connector to your crank sensor, and make certain your 10mm bolt hasn't wiggled free somewhat.

Last, a power stage will also cause a similar problem, as the spark will become weaker the hotter the car gets. This component sits on your inner fender on the driver's side. Make certain it is securely grounded on the fender, and that the connector is clean.

Chris

Chris, you bring up an interesting thought about the pre- heat hose connected to the air filter box. However, most of the past winter I never had it connected because it was all busted up and I just ripped it all off. Then just about a month ago I picked up a new one and slipped it on.

Why this is interesting to me, is that I didn't have this problem through out the winter unless it had warmed up outside. I recall last February I had the stall out and at that time changed the fuel pumps. It went away until this spring when the outside air started getting warmer and I didn't have the hose on at that time. I seem to think that when it was very cold out the car rarely missed a heart beat. So I wonder if the air mass is cooked or has been form some time.
Where is the air filter box thermostat??? I would like to check it out.

I have another air mass meter on the way from Stranbergs auto yard in Wisconsin. BTW they are big on Volvo's so if you need something you should try them.


Thanks
Judd

Take off the rear portion of your air filter box, the same way you take it off to replace the filter, just a bit more so. Look down in the front plastic portion and you will see a brass cylinder with a little post. This is your air filter box thermostat. You are supposed to replace them anytime you replace the air mass meter, but down here in Florida, land of no ice, I never worry about it since I yank the preheat hoses.

Strandbergs....I adore John and Kevin; they know me well. Even though they are so far away from me, they work with me on the price of their engines and such, since I rather purchase from them than anyone else.

Chris

I read this on another post...

"If the temperature is above 60F and your old stat has the flapper valve closed against the heated air inlet, it's working OK"

I check mine tonight and the flap is covering the COLD AIR intake. The outside temp. is in the mid 70"s here and I am wondering if this is a good indication that the stat. is stuck? If so then I could have cooked the mass meter.

What do you think of buying the after market Stats. Or should I go to the dealer for the whole thing? I did notice that the flap seals look ok not great but ok.

Judd

Since I so seldom purchase them, and since when I do it is because one of my customers is either visiting colder climates, or moving to colder climates, and I rather not have them run into any problems when I'm not readily accessible, I purchase the Volvo ones. Other folks on this board can probably answer your question better since I'm certain many live in a land of ice and snow, and may well have purchased an aftermarket one.

Yes, it is possible that your air mass meter is cooked, and the only reason I would be leaning this way is because you have a code for it. There are two other components that are greatly affected by heat, and they would be the coolant temp sensor, and the heated 02 sensor. Next time this happens, unplug the 02 sensor and see if the problem lessens. You can't unplug the ECT, but you can check resistances. Anyhow, hope this helps.

Chris

OK Judd, I feel you pain, but look at it this way; you've done great preventative maintenance where it should be done. Because it seems to be related to temperature I have a suggestion that could be a very inexpensive part(especially compared to what you have spent thus far). It may not be engine temperature, but rather the temperature of the main fuse under the hood.

On the drive's fender wall (up toward the firewall) is a main fuse in a plastic holder. The fuse connection tabs and particularly the fuse holder connections can get corroded (even thought they may not look like normal corrosion; maybe just discolored or glazed from the heat), causing high resistance, which causes high current and overheating the connections the longer the car runs. Eventually, it will starving the computer signals for power. This in turn causes the computer to get wacked out with weak signals (could explain various sensor failure codes that computer is seeing) and eventually stopping the engine.

If want to try and clean it you can, just to see if any improvement, but I would suggest you get a new fuse and good weather-roof holder. It's cheap. You might find something to do the trick at a place like Radio Shack until you good replacement. My son has a marine grade holder in his 89 240.

Hope this is the problem. Symtoms sound like it.

Gary

I will replace the fuse and the holder due to your suggestion! I might as will change the knock sensor and the temp sender while I'm at, since I have just about completed everything else. As far as spending allot and yet not getting to the problem, I feel that over the nine years of having this Volvo the dollar cost average has been CHEAP to own this car! People always raise their eyebrows when you mention that it's a Volvo and you've got problems. Their seeing dollar signs while I am seeing nine years of service starting at 80,000 miles, to their "traditional"(avoiding the use of American) made car dollar hungry before it turns 90,000....I think I'm just over the 150,000 mark and with the body still in good shape, I'm enjoying this elusive mystery.

Well keep sending your thoughts and I'll keep plugging away.

Judd

I wouldn't do the knock sensor...they almost never fail.

That's the way I look at it after having 4 volvo (currently 2) with over 200,000 and running strong.

I have no real good ideas but a couple of notes I have made from Brickboard (no direct experience) about bogging down causes include a bad knock sensor and of course a plugging cat.