I have a 2002 v70 with 24k miles. It surges when stopped while in drive, for example at a traffic light. The engine speeds up and slows down about 4 or 5 times in rapid sucession and then runs smoothy for about 15-20 seconds and the whole cycle starts again. Does not do it in park. Does not matter if the AC is switched on or not. Does not matter if the car is hot or cold. There is no noticible movement on the tach while this is going on. It was bad enough tonight that the lights would dim during the slow part of the surge cycle. The car never has come close to stalling and otherwise drives pretty good. It's really annoying.

Earlier this year, the dealer replaced the throttle body. This helped some, but did not totally cure the problem. Last week, the dealer cleaned the throttle body. Again this helped, but did not totally cure the problem. The dealer says there are no codes in the computer. I'm pretty frustrated with the car right now. I took matters into my own hands and just replaced the air filter, as the most recent work order from the dealer said "failed minimum air flow". It was the original filter and was in marginal condidtion. The car was better for about a day and now we are back to surging. So, it's back to the dealer next week.

Does anyone have any ideas? It's obvious the dealer doesn't have a clue.

Thanks,

Jeff

If changing/cleaning the throttle house didnt help, its probably the electronics in the throttle steering that needs to be replaced. They are known to cause the problems you describe.

NEVER heard of such a notion. Care to explain?

If nothing else helps (cleaning/replacing Throttle/MAP etc), test the car with an ECU from an identical car without the problem. Quite often everything is just dandy with another board, which leads me to think that the problem is related to electonics in the throttle steering.
But I've NEVER heard of such a notion from Volvo either, so maybe it's just me imagining things ;-)

Who here has access to another identical parts car with the SAME software besides a dealer tech at a dealer to even try such things, not to mention LABOR time paid?

I was trying to be serious and with known facts, TNNs found currently in the dealers VEN system such as the # I listed (twice here now) below.

See, this topic re-occurs yet those who complain here apparently don't care enough to take the car to their dealer with the info listed below. Volvo knows of a few problems and ONLY a dealer with a good tech who cares (a VERY RARE breed these days) will EVER solve the problem.

I agree. But when someone posts about problem like this and says the "dealer tech has no clue", my thought was that he can give some suggestions to the dealer tech. And if the tech has access to VADIS and a similar car he surtenly can try another ECU and maybe isolate the problem quckly.
To change ECU yourself is not possible because the immobilizer will not clear a different ECU.
The throttle/surge problems is very common with 2000-2002 Volvos, unfortonatley though there's many possible causes. The MAF is one strong candidate, soot in the throttle is another.
But also (and especially with the 2002's!) the throttle electonics in the ECU is a likley cause. I'm not unserious I'm just trying to help, but english is not my first language so maybe you misunderstood. I did also not see your previous post when I posted.

In recent days we've seen a couple of cars that matched the criteria of the TNN that I listed. The cure for THAT problem requires a replacement transmision valve body with seals. IF warranty, it's a 5 hour job and FREE to the customer. If NOT warranty (too many miles), it's about $1000 in parts plus the labor SO not cheap.

Being a tech, I have yet to either read (from VCNA, Volvo) or hear from any VCNA people to "try swapping ECUs" to cure THIS problem(s) as listed. Also being that most dealer techs are strickly flat rate techs, UNLESS someone's paying the tech to do "try me parts", no tech will bother anymore.

This same question was discussed here not long ago. Although both ETMs and MAF meters are THE most common problem causing idle fluctuations (even w/o codes) and a MAF meter can be easily installed as a "try me" attempt before assuming something more serious, like what I'm listing here below, IF the car was built before 1/02 production date and non-turbo, have your dealer refer to TNN 43-38 as that MIGHT BE the solution. I have never seen a need to do that yet in our dealership but the problem is known with a solution.

If that doesn't apply to your car, has the dealer tech tryed calling the tech hot line? If the problem can be duplicated (not intermittant), they should be able to fix it.

There are other known TSBs on the subject too as idle, surge related problems with newer cars are hardly rare these days. Sometimes it's a software upgrade too.

Here's the older thread :http://www.brickboard.com/AWD/index.htm?id=696690

Well if you find out what the fix is would you please post it here? I have the EXACT SAME symptoms with my 2002 V70, non-turbo. I also had my throttle body replaced, it shorted out at 15,000 miles. I currently have 23,000 miles on my V70 and the transmission bucking, jerking has annoyed me from day one! It gets so bad at times that passegers in my car think that I'm pumping the brakes and jerking the car back and forth!

Again, if you do get this problem resolved please post the fix here. I haven't had any resolution from my Volvo dealership in this matter, although they have been earnest in there efforts, they can't figure it out.
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