Signs of a failing ETM and its relation to the MAF sensor

[nyteacher]

What a great collection of helpful posts!I have a 2004 v70 that actually runs well almost all the time and gets good gas mileage (avg. 28-29). I do have the hunting at idle issue and it will stall once in a while when braking, especially going around a corner and braking. I replaced the MAF and that helped slightly. I get an intermittent code (not showing presently) something about the barometer or barometric pressure. Have you heard of the ETM issue affecting 2004 v70's? Do you recommend my getting the diagnostic test mentioned for the ETM? Thanks.

[TedWPost]

Just want to post this so others searching out the answer for their problems get all the information possible.

Long story short, I have a 2000 xc70 that I replaced my ETM with an XeMODex version a little over a week ago and it has cured the issues I was having completely. I'm hoping and confident it will stay cured.

What's a little different in my story is that I never experienced the "hunting at idle" and could never get the car to bounce the rpms around after reving it up with the brake on.

What I did have for symptoms are:

1) Wild fluctations in rpms between 1500-2000 when the car was first started (I would say cold but its summer here). I'm guessing this was very much like the "hunting at idle" condition, just a completely different RPM band.
2) A lot of "wind gusts" when driving highway speeds, usually under light acceleration. No acceleration or heavy accelartion never showed the issue.

So reading the above steps it really seemed like all I might have was a bad MAF. I had cleaned the MAF earlier and it didn't change a thing. But I first replaced the MAF completely and it didn't help at all. The following week I got my XeMODex ETM and replaced it (3 hour job for a non-mechanic but reasonably handy person) and all the symptoms are gone.

So the gist of the story for me is that the fluctations in rpms may not be at idle.

Ted

[caleula]

Not sure about my problem fitting "the mould" so to speak. It's happened a few times over the last year and normally goes away, however, today's episodes were more severe. Usually at traffic lights or going slowly, the car rocks [shudders?] as if trying to go back and forth constantly. Silly me didn't look at the dashlights, however, I stopped the car and started it again with hardly any improvement. It happened about 4 more times on the trip.

Probably unrelated, but I had a new alternator fitted last year and approximately every 3 months or so the battery goes flat. The charge has been checked and is okay. In fact, I lifted the bonnet before going out today and the green light in the battery indicated it was healthy as did the digital voltmeter I have mounted in the cigarette lighter socket.

My mechanic was flat out trying to fix someone elses major problem so didn't have time to check the diagnostics. He did ask whether I wanted to sell the car as he might have a buyer. Problem then is I'd need another car and have had 7 Volvo's since 1974. Even won a prize from Ford [who have now sold to Geely] when I wrote complaining that Volvo Magazine wouldn't be sent out to owners who had vehicles older than 6 years. I countered with such owners probably helped build Volvo's reputation and sales in Australia.

[schmidm90]

I am having similar issues with my 2000 V70XC. The other day I noticed the rpm's were jumpy when I had it in drive sitting at a stop light. Then once I accelerated, the problem got worse until I reached 30mph and then all of a sudden it ran great again. The problem continued to get worse to the point where the whole car would shake when I tried to accelerate. Finally the check engine light came on and the code said "Misfire in Cyl. 4". I replaced all the spark plugs with NGK Platinum(what was in there before) and the problem seemed to go away for the day. The next morning I drove to work and all of a sudden on the highway it felt like the tank was empty and the engine was really stuttering. Then once I got it up to 65mph it went away again. I tried to clean the MAF last night and it seemed okay and then started to stutter again when I was stopped at a light. It is worst in reverse gear but I have not felt it in park or neutral.

I have read a little about either the MAF or ETM needing to be replaced. I will try to find a MAF from a junkyard for a few bucks and see if that fixes it. I have read that I might need to get a software upgrade at a dealer for that? Finally is the ETM the same as the throttle position sensor? FCP Groton has one for $55 but I wasnt sure if I have to replace the whole throttle module which is significantly more.

All help is greatly appreciated!!!

[jcmahoney]

Just as an add - I had my ETM replaced in around 2004 - shortly afterwards I had to replace the MAF. I made no connection.

99 V70.

Cheers.

[volvamos]

Well I just bought my second Volvo, this one is a 2000 S70 with about 115,000 miles on it. Sure enough a few weeks after purchase I noticed some choking while accelerating up to 20mph, then the "ETS" light came on intermittently. Now I think it stays pretty much on.

Total bummer b/c obviously this car misses the Extended Warranty by some time. I called and tried the "plead and beg" method with two local Volvo dealerships to no avail...$1500 and $1200...ouch. haha.

Since it's not my daily driver, I will attempt to clean the ETM real well and give it a go. I don't have much hope for that, so I imagine I'll send it in to xeMODex to get fixed up. I'm not able to do ALL my own work on the Volvo's, but I'm getting better. Here I'll potentially have to remove it twice and install it twice, ought to become an expert!

[sckerber]

ETS light has come on. Engine dropped to idle, originally thought it quit but only ETS and check engine light came on. I know this is an old thread, but I had slightly different experience so decided to share. Originally car experienced several months of gradual power loss made most noticeable pulling into traffic and even stomping on throttle to to point where engine kicked down, revving the engine, but barely moved car. Felt like my old diesel Rabbit with a clogged fuel filter and a cement truck on my back bumper. Changing filters and cleaning MAF had no effect. Finally after consulting forum, I unplugged the MAF and eureka! it worked again. New MAF did the trick. There was some surging, but had not make any connection to the above problems. 5k and several months later, hello ETS light, the cruise control has also quit working. I've talked with dealer over the phone, who checked my VIN and told me that I have updated software; so guessing previous owner has already had ETM replacement done at least once. XeModeX folks have confirmed diagnosis. Right when I was trying to sell car,,, swallow hard, and demonstrate the car has been conscientiously maintained.

[nzvlnr]

So is the end result to replace the ETM? MY CAR IS A 99 S70T5 and I am experiencing a miss, some intermittent idle issues. But I think it will fail (already replace the MAF and the PVC system) from what I read it should be addressed. My car has 139k on it

[jaredNYC]

I drive a volvo 850 glt 96 version and its starting to show all of these symptoms most recently the sluggish behavior when I'm hitting the pedal on the highway.

Very informative but I'm still confused about one thing.
It seems that you're suggesting that I just replace the MAF sensor and keep driving.
And, perhaps cleaning the throttle body myself.
But I guess no matter how you cut it at some point you're going to have to replace the throttle body.
If I do replace the MAF, how many more miles am I going to get before the throttle body film confuses the MAF again?
Thanks,
Jared

[Matty Moo]

I drive a volvo 850 glt 96 version and its starting to show all of these symptoms most recently the sluggish behavior when I'm hitting the pedal on the highway.

Very informative but I'm still confused about one thing.
It seems that you're suggesting that I just replace the MAF sensor and keep driving.
And, perhaps cleaning the throttle body myself.
But I guess no matter how you cut it at some point you're going to have to replace the throttle body.
If I do replace the MAF, how many more miles am I going to get before the throttle body film confuses the MAF again?
Thanks,
Jared

The etm info isn't applicable to your car.