Reduced Engine Performance only in the Winter at Code Start

rbritt5 · Post by **rbritt5** » 20 Dec 2016, 07:17

HI, I have 2005 volvo S60 2.5T AWD, and I have been having an ongoing problem with my car for year now.
Last year start Nov 2015 I had message "reduced engine performance" and the engine sound rough. I took it to the dealer, no codes found. Then ran fine for another month. Dec 2015, same thing but by the time I got to the dealership the CEL had went off and no codes. Jan 2016, same thing, took it to firestone since they where the closes, code p2111 and they said volvo would have to fix it, so I told it to Volvo dealership and they said there was no codes, and having the code p2111 could be multiple things and was not going to test everything that could be wrong with it and told me to bring in back in when the CEL came back on. So almost a year later, Nov 2016, reduce engine light came back on, so i took it start to volvo dealership, they said code was throttle and idle control system, and said that it happens in the cold for older cars and for me to bring it back when it came back on. (Didn't make any sense to me then they know I have been having this problem since last year). Happen again about week later, with a code P2111 and P0507. So finally I took it to someone else that works european cars. When no CEL on or reduce engine message she had the code "120D (P0100), 925 (P2111), 951C (P0507), 120C (P0100), 310C 314C 315C (P0300 misfires), 4400 (P0461). The weird part about it, it only has a rough cold start first thing in the morning when the temp drops blow 32. So every morning now the reduce engine performance message comes on and the engine sounds like it about to shut off but it doesn't. I can turn it the engine off and normally it will start up fine on the second start. some times when it really cold I have to cut off and on a couple of times. So I drop the car off to the lady that ran all the codes, and she said that it ran like crap at first and she plugged it up there was no TPS. and that it started idling fine within 5 mins. and had code 9270 (P0638 Throttle Unit Faulty Signal) and 120D (P0100 Air Mass signal too low) and believe the throttle and MAF meter is having problems in the cold? That I would need to replace the Throttle and MAF sensor.

I don't know that much about cars but I have been doing some research on this. If the throttle or the MAF sensor was going bad, wouldn't it do it all the time and not just in the cold? I know I had the throttle body clean in Jan of 2014 with about 140k and now I almost have 200k. I have had the fuel pressure sensor replace in April of 2015. I'm just worried that if I just replace the sensor and the throttle that might be more problems. Every webpage I visit either say that they should never need to be replace or just cleaning them will on do a small fix and talk about how the car has idle problems when driving it. I don't have any problems driving it after the first cold start. Cause once it warms up, it goes back to normally, i feel that my problem doesn't related to any of the stories I have read so far.

Has anyone had this problem before or can help me figure out what the problem could be. I know with all the new sensors they can be sensitive. I don't want to replace something if theres nothing wrong with it.

Thanks.

Post by **abscate** » 20 Dec 2016, 07:35

When these cars run rough a bunch of codes get thrown which can divert you from the real problem. Thats sounds like what is happening here.

The throttle body on the 2005 is a reliable BOSCH unit which usually just needs cleaning. If the car hasn't had regular synthetic oil changes it could be dirty again.

If you can trust the code reading that did not show the TPS, that is indicative that that part is bad or has a bad connector. The best thing for you with an intermittent problem like this is get your own code reader so you can nail down what comes first. They range from $20-$200 for these cars depending on how much function you want.

No mechanic wants to diagnose based on customer descriptions - they are just too often wrong and full of bad information. You either have to authorize parts replacement or authorize diagnosis.

rbritt5 · Post by **rbritt5** » 20 Dec 2016, 08:17

Thanks for the quick reply. I do change my oil every 6,000 miles and is mostly HWY driving and I either use full synthetic mobil one or castrol oil.

But if the part was bad or had a bad connection wouldn't this problem happen more often then just the first start in the morning? That what makes me question if the code reader is correct

Should I just start with cleaning the throttle body and MAF sensor first and then go from there and see what happens? If so what is the best way to clean the MAF sensor, I have see 3 ways (take the whole sensor off, just the sensor with you have to have a special tool or just spray in the air box) but I don't want to damage the sensor.

rbritt5 · Post by **rbritt5** » 20 Dec 2016, 08:20

Oh is there a good brand or type of code read for Volvo? I know some will show the temp and volt for the sensor, etc and I believe thats what would be best for my car?

Post by **chrism** » 20 Dec 2016, 08:26

I'd say don't buy ANY new parts - at least not yet.

"... I know I had the throttle body clean in Jan of 2014 with about 140k and now I almost have 200k...."

Sounds like cleaning the throttle body would be a good place to start. When reinstalling it, make sure the wire harness connector is good and clean and firmly attached. Then see how it runs over the next couple cold mornings.

Post by **oragex** » 20 Dec 2016, 09:34

It is not a common issue, and with almost 200k miles, there could be quite a few things that can go wrong. Reason why the main dealer doesn't want to look at it (translation of "there are no codes"). Somehow this is a good thing because other dealers would instead start replacing all but the spare tire.

How does a pcv system test do? Cleaning the throttle body (in and out) may be a good idea, not easy to access, and not a guarantee.

May be a sensor, even a front oxygen sensor, or a fuel pump, etc. But as above, starting to replace parts one by one will perhaps only prove to be a waste of time - and money. Perhaps try pulling parts from a scrap yard and test them. MAF sensor cleaning

Post by **abscate** » 20 Dec 2016, 09:44

You remove the MAF and use a spray (I like the CRC products best) for the sensor. Dont touch the sensor with anything - its fragile - just spray from can, catching the spray onto a rag.

MAF cleaner for MAF
TB cleaner for the TB

You can buy a 2 pack of one each for about $10

Post by **jimmy57** » 20 Dec 2016, 20:53

Sure sounds like the throttle is dirty and when it parks closed when engine is hot the cold contracts it and it doesn't open when you start it cold. Low air flow makes it miss and MAF value is far below normal.
It would be best to clean throttle without unplugging the connector. The connectors give problems with age and are best left untouched. The hose can be removed and the throttle unbolted and turned to clean.

rbritt5 · Post by **rbritt5** » 05 Jan 2017, 07:50

So i cleaned the throttle body yesterday, and it was dirty around the blade (attached a photo). I cleaned it up really good. This morning it was 32, and started up fine. So I think I solved the problem, but time will tell. Suppose it be 14 this Saturday and snow, so I'm crossing my fingers.Thanks to everyone that posed.

rbritt5 · Post by **rbritt5** » 05 Jan 2017, 14:54

SO two codes p2111 and p1167. I know about p2111 but can't find what p1167 is on a Volvo?