Hi - I'm a long-time 240 owner (seven cars over a decade!) looking at fixing a problem on our first front wheel drive Volvo (a 2wd 1988 v70). The check engine light is on. The OBD codes are P0107(Manifold Absolute Pressure/Barometric Pressure Circuit Low Input) and P0410 (Secondary Air Injection System Malfunction). Can a bad air pumb throw both codes, or could I really have a bad manifold pressure sensor AND a bad air pump. The symptons are consistent with a bad air pump: hard cold starting, cooling fan that runs when the engine is not hot, and running a little rich.

This problem happened after a bit of a cold spell, so I assume the air pump may have frozen up. Is there a fuze that might have blown before the air pump was ruined? If so, where could I find the fuse.

I was a bit surprised to see how expensive the air pump and check valve are ($359 and $122, rexpectively at eEuroparts).

Cash is tight right now, and I would be grateful for any suggestions that allow me to fix this problem without dropping a grand at a garage! Thanks. Glen

Hi GlenP,
If indeed your air pump is toast, here is a procedure to replace it with a pump from a vw. These are much cheaper and easier to find in working condition. As mentioned in the article i also got a pump off ebay for about $50+/-. The switchover was a piece of cake... very easy procedure. Link is here:

http://www.matthewsvolvosite.com/2009/10/24/air-pump-fix-tutorial-volvo/


Also I experimented with the vacuum valve(mushroom looking thing). When i took it off the motor i ran some PB Blaster thru it and it immediately leaked out the bottom. Over a couple of days I kept spraying away with the PB. Eventually the PB stopped leaking thru and the valve was sealing closed again. I suspect it gets crudded up much like an EGR valve does over time. This was 1 1/2 years ago and it is still fine... of course I did drill the drain holes into the body of the new pump.

hope this helps,

Dan

p.s. this was on a '98 s70

Dan - I read your article and it was superb. If I have to replace the pump, I will surely use your method. I am also going to try your trick with the valve, just in case! Thanks. Glen

Hi GlenP,
You are welcome but I cannot take credit for the air pump writeup.... that was written by someone on MVS. I just followed the procedure. Also the vacuum valve/ PB squirt was just a "what have I got to lose" thing.


Dan

The MAP sensor doesn't do anything important. you can try cleaning the connectors on that one and see what happens. It's just behind the windshield washer fluid jug.

The symptons are consistent with a bad air pump: hard cold starting, cooling fan that runs when the engine is not hot, and running a little rich.
No, those are a bad ECT (coolant temp) sensor.

The air pump doesn't do anything either to affect the running of the car. Do you hear a whining at all after you put the car in gear, drive around for a bit, and stop? Often times the air pumps are killed by moisture getting down into the system (my car has had 4 in its history before I owned it)...Klaus here recommends drilling holes in the housing to let the water drain out. If you need to pass emissions testing, this will need to be fixed, otherwise it's not important. I kept clearing my code for months before it finally got on my nerves enough to fix. It is expensive, there is a write-up over on MVS for retrofitting a VW air pump to a Volvo and save yourself quite a bit of money.

I'd start by replacing the ECT sensor and thermostat. You can pick up a MAP sensor at a junkyard - they are very expensive new.

JA - Thank you so much! Come to think of it, I did notice that the coolant temperature on the instrument panel goes to operating temperature as soon as the key is turned on. Would this be another indication of a bad ECT? Glen

With a cold engine? Yep, replace the ECT sensor soonest. If you are good, you can unscrew the sensor (just below the thermostat housing) to almost falling out. Then rapidly take it out and slide a finger over the hole with your free hand. Carefully start the new one in the grooves and you will be good to go.

If you intend to change the thermostat, I suggest draining about 1 quart of anti freeze before starting. I killed my alternator by allowing AF to leak all over it :( And make sure you have a very good T40 driver with a 4 or 6" extension.

The MAP is secured to the right inner fender, just a small black box. Always try cleaning the plug and connectors before buying new or going to the junk yard. Do not unplug anything if the engine is running or key is in posII.

Your blower can be dead, I forgot to look up the code. If it is real cold out, collected water can freeze and kind of ruin the pump motor. Drilling a 1/8 hole in the cover at 6 and 4 o'clock allows any condensed water to drain out.
Listen for the pump motor for the 1st 2 minutes from cold engine start.

Klaus
--
Proud owner of a 220S. If I had more room, I would have more Volvos.

Klaus,

I have been monitoring the s/v/c70 boards since we got the v70 and seen many of your posts. You, sir, are awesome. Volvo should put you on a retainer. Forgive the gushing, but I feel honored to have you respond to my question!

I usually get my 204 parts from FCPG, eEuroparts, and GermanAutoParts.com. I try to split my business to keep multiple suppliers healthy (and with six running 240s on the road - four for our oldest kids, mine, one in reserve - I buy a LOT of parts). I'dlike to do this job over the weekend. Is it possible that I could find the ECT sensor at a parts store (AutoZone, NAPA)?

Thank you for the tips. I hope I don's have to buy that air pump!

Glen

looks like dealer and FCP are the same price. I think it is OEM only, so call the dealer tomorrow and ask parts for a 'nice" price. VCNA members get 10% off, and no shipping :)

Let the engine cool off before changing it out.

Klaus
--
Proud owner of a 220S. If I had more room, I would have more Volvos.