2000 V70 hesitates slightly while accelerating

Post by **egornygr** » 20 Nov 2012, 14:23

I have a hesitation issue I could use some help figuring out. I've got a 2000 V70 fwd, no turbo, with 188k miles.

It will periodically hesitate slightly while accelerating, and occasionally when it is at a constant low RPM under load it will kind of "buck" where it slows and accelerated in rapid succession - wavering between 1,600 and 2,000 RPM despite the fact that my foot is steady on the accelerator. The check engine light is not on and there are no codes.

So far I have done the following:

- Replaced mass air flow meter
- Replaced fuel filter
- Replaced spark plugs and wires
- Ran through two cans of Seafoam in two successive tank fulls of gas
- Taken it to the dealership which was unable to replicate the problem

It seems like a fuel system issue, and the only other thing I can think to do is have the fuel pump replaced.

Before I do that, I was hoping to get a few additional thoughts on what could be causing this. Any feedback would be greatly appreciated.

Thanks!

Post by **Ozark Lee** » 20 Nov 2012, 15:51

Which ETM do you have? The white sticker, the yellow sticker, or the Xemodex modification?

...Lee

Post by **egornygr** » 21 Nov 2012, 08:56

White sticker.

Post by **Ozark Lee** » 21 Nov 2012, 11:00

Your symptoms are fairly typical for a ETM that is beginning to fail. There was a recall and Volvo should replace the white sticker version with an "improved" yellow sticker version. The yellow sticker is better but still problematic. There is more information on the recall and the procedures to get the recall work done in the Don's ETM Room forum.

...Lee

falconbrother · Post by **falconbrother** » 21 Nov 2012, 17:07

I have a 2000 V70 that had the same symptoms. I cleaned everything, tested what I could and kept getting erroneous codes, etc.. Finally I came to the conclusion that it may be a coil pack. I waited a few days and finally got a code for coil pack #1. I ran up to Auto Zone, bought a coil pack and that fixed the issue.

Post by **precopster** » 23 Nov 2012, 05:53

I'm afraid there was never any "recall" in North America, only an extended warranty to 10 yrs or 200,000 miles (whichever first)

You can send the unit to XeModex in Canada who will upgrade the ETM to contactless angle sensing operation and perform a firmware upgrade to the latest for your vehicle. They can also send you one matched to your car and refund a core charge once they receive your unit.

Post by **egornygr** » 23 Nov 2012, 07:40

I went through a lot of the info on here about the issue, and I've concluded that the ETM is almost certainly causing the problems I'm experiencing. Last night I ordered the XeMODeX unit. I'll post a follow up once I receive it and get it installed.

While the unit is certainly not cheap, I can't really be that upset given the fact that the original unit worked properly for well over 150k miles...

Post by **egornygr** » 02 Dec 2012, 08:06

The Xemodex ETM is now in the vehicle, but I'm still having some problems.

I ordered the unit through their website, and the next day the xemodex folks called me and said that there were two possible software configurations for my vehicle and they would send me the most common one. As luck would have it, it didn't work. While it seemed to idle ok, the unit was making a buzzing noise, and the engine responded violently if I pressed the accelerator even slightly. They sent another unit with the alternate configuration which is now in the vehicle.

Nevertheless, I'm still experiencing something funny. For the first two days everything was great - the car drove like new. But then I noticed the return of another "computer" problem I was having with the transmission. A few weeks ago I had the dealer update the transmission software which fixed an issue I'd had where it wasn't shifting properly. But that issue seems to have returned.

Could the "wrong" xemodex software have somehow corrupted the transmission software, or could it just be a coincidence?

Post by **precopster** » 03 Dec 2012, 05:31

egornygr wrote: So far I have done the following:

- Replaced mass air flow meter-
- Replaced spark plugs and wires-

Did you use a genuine Denso MAF or a rebuilt MAF??

There are no spark plug wires on these cars, only five separate coil packs
Some of your symptoms can be intermittent coil pack breakdown so it may be worth getting hold of some new ones.
eBay seller swedish_autolamps_plus have a 5 coil pack low buy price: http://www.ebay.com.au/itm/Volvo-Igniti ... 53efc0426d

If they are the original coils it may be worth a try I don't believe in corruption of the TCM by the ETM. What symptoms were you trying to get rid of in the 5 speed?

Post by **egornygr** » 03 Dec 2012, 05:56

The MAF is genuine Denso. Already replaced the coil packs (wires).

The original issue with the transmission was that it was not shifting smoothly, particularly in low speed situations where I had to slow down and then speed up again - for example slowing down from 30 for a light that then changes to green once I'm nearly stopped. I hit the gas and there is nothing, but then it kind of kicks in after a second.