1998 V70 T5 Manual Emissions Issues

Post by **misha** » 19 Jan 2015, 05:27

Bad ect would have a code for it but....bad thermostat,if it's stuck open would also be a culprit for high fuel consumption.

Is your temp gauge always in the middle even on highway on cold weather?In stop & go city driving it will always be in the middle(3 o'clock mark),but as soon as you go open road it would start falling down.

Did you tried to reset ecu in order to reset fuel trim adaptives like i suggested?

I just read your post about boost leak.You must sort out those little problems you have.Maybe there is a problem since the car is turbo.

Seaway · Post by **Seaway** » 19 Jan 2015, 05:33

misha wrote:Bad ect would have a code for it but....bad thermostat,if it's stuck open would also be a culprit for high fuel consumption.

Is your temp gauge always in the middle even on highway on cold weather?In stop & go city driving it will always be in the middle(3 o'clock mark),but as soon as you go open road it would start falling down.

Did you tried to reset ecu in order to reset fuel trim adaptives like i suggested?

The thermostat seems fine as it goes to the 3 o'clock position and sits there, regardless of whether I am driving in town or on the highway. I just had a bad thermostat on my other 1998 V70, so I know the symptoms well.

I reset the ECU yesterday when I was in the engine bay. Unhooked the negative and positive cables and zip tied them together for the 3 hours I was working on the car. Unfortunately, I am not going to be able to get any real numbers on what is going on until I get the rear O2 sensor in. As of right now I have a hole in the exhaust where it is supposed to be.

Post by **misha** » 19 Jan 2015, 05:36

You need to get that o2 sensor back in it's place in order to continue further.

Seaway · Post by **Seaway** » 19 Jan 2015, 05:39

misha wrote:You need to get that o2 sensor back in it's place in order to continue further.

Yes. I should have it in place on Tuesday. With any luck that will solve the problem. I don't have high hopes.

Post by **misha** » 19 Jan 2015, 09:25

Without properly seated it can't sent valid measures to ecu.

We'll see.

Seaway · Post by **Seaway** » 20 Jan 2015, 05:15

Well, I went to drop the downpipe off the turbo to better access the rear O2 sensor and one of the studs holding the downpipe to the turbo exhaust flange was snapped about two threads into the housing. It appears to be an old break as it is rusted on the broke surface. It was basically finger tight and not doing much to hold anything together. Since this is upstream of both the O2 sensors I am guessing it may have contributed to my problems. I guess my options are to drill out the stud and through bolt it, drill out the stud and tap it or to use an exhaust C clamp to hold it together in the broken area. Not really too bad a fix since it is the stud on the top left of the exhaust flange. Access is pretty good.

Post by **abscate** » 20 Jan 2015, 10:59

5 USD clamp from HF and don't forget to write VOLVO on it in sharpie, so that its clear you are using OEM emission control parts.

Seaway · Post by **Seaway** » 20 Jan 2015, 11:16

abscate wrote:5 USD clamp from HF and don't forget to write VOLVO on it in sharpie, so that its clear you are using OEM emission control parts.

Ha, good thought on the sharpie. I have already picked up some flange bolts that should do the trick, I am going to put the heat shield back on the turbo so nobody can see what is going on back there. Hopefully that will discourage them from picking it apart and actively trying to find things to charge me for.

Seaway · Post by **Seaway** » 20 Jan 2015, 17:47

After almost two hours of struggling with the back tap, I finally got the threads fixed in the catalytic converter bung. Not a fun job to have to do on your back. I got the O2 sensor in no more P0131 or P0141 codes anymore. But I did manage to get a code for the MAP - P0108. I am going to swap the sensor from my other car and also swap in the known good MAF sensor and try to get it inspected again. I spoke to a mechanic I know and he said he would "get it passed" so we shall see.

I still need to drill out the broken stud at the downpipe, but I need a right angle drill to do it and I am going to have to borrow one from my father. That should be fun. The space was about three inches too short to fit a regular drill in.

I also sprayed carb cleaner at every vacuum connection and hose and could not get the engine to change idle so it seems that I may not have any vacuum leaks after all.

Hopefully by this time tomorrow the car will be inspected and registered so I can actually drive it!

Post by **misha** » 20 Jan 2015, 18:42

Map sensor reading depends on vacuum.So,it's directly connected to intake manifold or there is a little vacuum hose which connects to it.

1998 V70 T5 Manual Emissions Issues

Re: 1998 V70 T5 Manual Emissions Issues