P2 2001 V70XC 'Stutter' driveability change with cruise on / cruise off

[jonesg]

in practice theres a difference,
a car in cruise cannot see upcoming hills and anticipate.
but the driver watching the road adds power in advance rather than waiting until the engine starts to lug down.
The steeper the incline the more inertia a driver can carry into the approach.
it might help to use the steering wheels control to add power in advance of a climb.

they say don't lug the engine down but cruise does that unless the road is flat.
i found cruise useful out in nebraska on those 400 mile stretches of flat straight roads.
Rarely use it here unless my ankles are aching from bad shoes, taking my shoe off works too.

[abscate]

Cruise will unlock the torque converter on an AT and even downshift. With my M56 cars, I might have had cruise drop on a hill climb once or twice that I can remember but certainly not with my T5.

Finding the bandwidth on the cruise control servo in software is going to be a challenge

[ignatz]

I'll give everyone my 2001 V70 2.4t experience and how I drive my V70 with the cruise control.
1....When I get on the turnpike, I get up to the speed I want to be at, then turn on the cruise control.
2....If I would pull over on the turnpike and leave the cruise control on, while pulling out and hitting resume, the car instantaneously goes into full "power" mode until it gets back up to 68mph.
3.....What happened to me? While driving on the Pa. turnpike, in a light rain, I disengaged the cruise control so I could go thru the S turns near the Lebanon exit comfortably without the cruise control. As I went thru the turns and am now going straight I hit Resume at 55mph.
The engine instantly went to full throttle causing a massive wheel spinning at 55 mph until I switched off the cruise control by hitting the brakes.
As I pulled over to the side of the road to catch my breath, I now had Triangle's and Warning messages telling me I over sped the engine.The messages would not clear by turning off the car, but went away about a day later.
4....So when I said above the car went into full power and not full throttle, it "seems" to me that the cruise control does more than pull the throttle down when it wants more power. Just an opinion from a V70 who had a terrifying moment at 55 mph.
5....I like using my cruise control, but use it more carefully in the rain and never hit resume unless I'm real close to my original speed I set the cruise control for.
6....And they were Michelin tires that broke loose.

[br0dy519]

Never use cruise control in wet/snow/ice conditions and never in heavy traffic nor in hilly areas. These are the rules I followed since I was 16 and never got into trouble yet.

[stevek924]

Sorry for the late (VERY late) response but I found the problem. Ignatz and leapdragon pointed me in the right direction, it was an ignition problem, my #3 coil pack was bad. Changed out all the packs & plugs and worked perfectly.
BTW, the '01 is gone. Got to the point of being BER (beyond economical repair) at 297000+ miles. Was a wonderful vehicle, bought used with 50K miles on it in 2006. Survived two accidents, both within a year of getting it (both repaired at the dealer I bought it from and they did a superb job). And in 18 years only failed me twice, a bad throttle module and a bad starter. Traded it last month for a 2010 XC70 with 115K miles on it. I'll keep my '04 S80 for another month or so while I put some miles on the 'new' one then donate it to a charity. It still runs and drives great with 295K miles on it, and has been just as reliable and comfortable as the V70XC, just don't need 3 vehicles anymore. The '02 Ford Ranger is a keeper for hauling things around the homestead and trips to the dump.

[scot850]

Thanks for getting back to us and giving the update. I hope you enjoy the P3 as much as you clearly did the 01 XC70.

Neil.

[volvolugnut]

I'll give everyone my 2001 V70 2.4t experience and how I drive my V70 with the cruise control.
1....When I get on the turnpike, I get up to the speed I want to be at, then turn on the cruise control.
2....If I would pull over on the turnpike and leave the cruise control on, while pulling out and hitting resume, the car instantaneously goes into full "power" mode until it gets back up to 68mph.
3.....What happened to me? While driving on the Pa. turnpike, in a light rain, I disengaged the cruise control so I could go thru the S turns near the Lebanon exit comfortably without the cruise control. As I went thru the turns and am now going straight I hit Resume at 55mph.
The engine instantly went to full throttle causing a massive wheel spinning at 55 mph until I switched off the cruise control by hitting the brakes.
As I pulled over to the side of the road to catch my breath, I now had Triangle's and Warning messages telling me I over sped the engine.The messages would not clear by turning off the car, but went away about a day later.
4....So when I said above the car went into full power and not full throttle, it "seems" to me that the cruise control does more than pull the throttle down when it wants more power. Just an opinion from a V70 who had a terrifying moment at 55 mph.
5....I like using my cruise control, but use it more carefully in the rain and never hit resume unless I'm real close to my original speed I set the cruise control for.
6....And they were Michelin tires that broke loose.

I also recently was driving in a hard rain with cruise control on. I had a similar wheel spin event and decided I needed to go with manual throttle control to be safe. It was exciting for a few seconds.
volvolugnut

[ignatz]

My 02 V70 2.4t cruise control works beautiful with the resume gently getting you back up to speed smoothly. My 01 V70 2.4t went to full throttle immediately as I posted years back. About a year and a half ago while on a steeper hill in Ohio, I hit the resume (my mistake) at around 50-55 mph and because the road was dry it must have over boosted and went into limp mode. Luckily I was at an exit ramp and pulled into a convenience store. After my bathroom break, the car started up and ran perfectly. Just a special triangle and a message warning that went away a day later. Sadly, a bad exhaust valve earlier this year sent my 01 to the scrap yard.