Volvo C70 2004 intermittent lagging/unresponsive.

zpsny91 · Post by **zpsny91** » 06 Jun 2017, 19:39

Hi All

I'm new to the forum and this will be my first post. I should have likely been a member before now, as I've been doing a lot of my own work considering Svetla (2004 Volvo C70 2.3 Turbo) would break me if I took her to Volvo every time she acts up.

The car has right at 105K miles. I keep her fairly maintenanced, and when something goes wrong, I address it quickly rather than letting it ride. The problem is, it seems like one thing after another and it can get hard to find the time to get things done.

Let me start from about a month ago and work forward. One evening during my drive home, she quit getting any real power and I couldn't get over 45/50 MPH and my check engine light started blinking. Aside from this, the check engine has never come on the 30K miles I have put on the car. I hookup up the OBD2 and was given a bad ignition coil code. I replaced the coils as well as the spark plus and air filter (both were about due). She ran like a dream for a couple of weeks. The past week or so, I have noticed the car very unresponsive and hesitant during acceleration. When you do give it gas, a few seconds later it seems like all of the gas it's been given during the delay 'kicks' in at one point. This seems to be intermittent but becoming more the norm day by day. When I first fire her up in the morning, I do not notice this problem. She also seems to be idling fine.The check engine light is not on and she isn't giving off any codes.

At this point in time, the TPS comes to mind. I'm confused as it seems like this would be giving a code and helping me be sure of the problem. I've considered needing my injectors cleaned etc. I realize we're looking at various symptoms and this would be very difficult to diagnose based on this. If anyone has experienced a similar problem and can provide what went wrong, it might give me somewhere to start, and would be very much appreciated.

Post by **bmdubya1198** » 06 Jun 2017, 20:51

Hmm... do you have any new codes coming up? This sounds to me like the throttle, but I'm not sure the 2004 still has that awful Magneti Marelli ETM. This definitely sounds electronic. It may be worth cleaning the MAF sensor.

zpsny91 · Post by **zpsny91** » 06 Jun 2017, 21:56

Hi, thanks for the reply. I do not have any malfunction codes at the moment. I will give cleaning the MAF a try tomorrow evening. I will let you know if I have any luck with that. Any other ideas are appreciated as well!

Post by **cn90** » 06 Jun 2017, 22:21

I had similar issues with my 2005 XC90 2.5T (similar setup as your 2004 C70)...
Cleaned the Throttle Body, problem solved!

See the DIY I wrote for 2005 XC90:

viewtopic.php?t=78629

zpsny91 · Post by **zpsny91** » 06 Jun 2017, 23:20

cn90 wrote: ↑06 Jun 2017, 22:21 I had similar issues with my 2005 XC90 2.5T (similar setup as your 2004 C70)...
Cleaned the Throttle Body, problem solved!

See the DIY I wrote for 2005 XC90:

viewtopic.php?t=78629

Awesome. Thanks for the DIY. Maybe I'm taking the OBD readings a bit too seriously, but I can't see why I wouldn't be getting a code from this. I will definitely try this. It should be an easy fix and much needed nonetheless, even if it's not the main cause of my problems.

Thanks Cn90

Post by **abscate** » 07 Jun 2017, 05:18

These cars are too complex to diagnose by symptom, especially when they are spurious.

You have pretty much covered the ignition troubleshooting with coils and plugs ( yeah ME7) so start with getting fuel pressure monitored at the rail. You can sacrifice a tire pressure gauge to read this. If the pressure is marginal, the suspects are

Fuel pump relay
Fuel pump
Fuel filter

In that order.

zpsny91 · Post by **zpsny91** » 07 Jun 2017, 16:52

abscate wrote: ↑07 Jun 2017, 05:18 These cars are too complex to diagnose by symptom, especially when they are spurious.

You have pretty much covered the ignition troubleshooting with coils and plugs ( yeah ME7) so start with getting fuel pressure monitored at the rail. You can sacrifice a tire pressure gauge to read this. If the pressure is marginal, the suspects are

Fuel pump relay
Fuel pump
Fuel filter

In that order.

Thanks for another idea of where to look abscate. I would be expecting a P023 code for that also. It's doing a lot of raining here today and will likely not try to do anything on her today being how I lack a garage. Interestingly though, Coming out of work today I caught a glimpse of this? Any idea what we have here? See picture.

Post by **abscate** » 07 Jun 2017, 16:53

Ambient temp sensor,,,not a biggie, near the front right side of car?

zpsny91 · Post by **zpsny91** » 07 Jun 2017, 17:00

abscate wrote: ↑07 Jun 2017, 16:53 Ambient temp sensor,,,not a biggie, near the front right side of car?

Correct, hanging down just behind of the front bumper.

Post by **bmdubya1198** » 07 Jun 2017, 18:00

Yup. Just your temp sensor. I think it goes in one of the grilles around the fog lights.