shaky idle, Transmission Fluid Temperature Sensor? S70 2000.

hud304 · Post by **hud304** » 30 Mar 2008, 18:09

Ok, here's where I am now:

- I took off the throttle body and cleaned it pretty thoroughly. I was never able to get that plastic boot off, but just cleaned it while connected. Anyway, this cleaning of the throttle body did not make the shaking go away.

- About cleaning the flame trap, I guess Volvo stopped using flame traps in 1998 (and mine is a 2000). See http://volvospeed.com/Repair/ftrap.php . However, there is still a line that goes to the air hose to the crankcase, you just can't remove it with a bayonet connector. I couldn't easily remove it, but maybe I should try to clean it? Any ideas?

- About the motor mounts, I was thinking it's probably not them, because the shaking only becomes strong when I put the car into Drive. In Park or Neutral there is no shaking. Wouldn't there be shaking in Park if the mounts were the problem?

- Also, there is a cricket/frog chirping sound near the belts on the passenger side, but *only* when in Drive. No chirping in Park or Neutral. Any ideas?

- I thought I read somewhere that maybe there was a recall on the 99-00 ETM's, so maybe I can get that replaced and see if that fixes anything. Probably wishful thinking.

- Finally, I manually redirected the air intake to cold, away from the hot exhaust, and that didn't do anything for the shaking.

That fact that it only shakes in Drive seems like a real clue...

Thanks again,
Ryan

Post by **MadeInJapan** » 30 Mar 2008, 18:29

Pull the smaller hoses off at the bayonet connector. If you can't, yes getting that connector off is a real shore. You have to push in and twist. It's easier done with the entire accordion hose out of the car. There is an inlet valve into the accordion hose. Clean it with brake cleaner and a hard bristly pipe cleaner. It should not be clogged. In regards to the ETM. Unless you're throwing an ETM trouble code the dealer will not touch it. Even if they do, their first step is typically to clean the throttle body- which you just did (but they might charge you). However, there might be a transmission/ETM software update to your car (but you'll have to give your dealer your VIN# to see if your qualify). If your car qualifies, the update is free and may alleviate the vibrations to some degree. From your description, I too do not suspect your mounts. The flame trap is a misnomer on your car. Many people refer to the oil trap under the intake manifold as the flame trap (but they're wrong). The oil trap (breather box, etc.) is part of the PCV system as is the hose that runs to the bayonet connector. The oil trap and small passages from it into your engine can get blocked too and should be cleaned if you have positive pressure in your engine. I guess you've read about measuring pressure from your oil dipstick tube or laying the oil fill cap on the opening to see if you have pressure at idle. Don't know what else to tell you.

bigfinn · Post by **bigfinn** » 30 Mar 2008, 20:25

With regards to the throttle body, I did not remove it for cleaning. I simply removed the hard plastic tubing that connects to the throttle body and sprayed cleaner directly on the throttle body plate (made sure to have a rag under the throttle body to collect cleaner run-off). Then manually opened the throttle body plate and wiped with rag that had cleaner sprayed on it.

The "flame trap" is located in the hose that connects to the hard plastic tube, which connects to the throttle body. (follow that?) The same one that I had to take off to clean the throttle body. You need to turn it CCW a quarter turn to release it. The flame trap had to be pryed out with a flat head screwdriver. (Be sure to have a rag handy, because oily goo will want to drip out). The flame trap is a circular part, about the size of a nickel, that has about 25 small holes through it. After removing it, spray it off with the cleaner. Also, use Q-tips to clean out the flame trap housing since you will need to reach the oily goo that is in the housing.

I know we have different year cars, but I did notice that the flame trap is available for purchase for S70's uears 1998 - 2000. I went to the following site....thevolvosite.com

So, do you have a flame trap or not?

hud304 · Post by **hud304** » 30 Mar 2008, 22:42

Well, I was able to pop off the hose that would contain the flame-trap, and there wasn't any flame-trap inside. It was just a hole that I could see through clearly. There was oil on the inside walls, which I cleaned, but it was definitely not blocked. See http://spt.uchicago.edu/blog/rkeisler/v ... nifold.pdf .

Regarding the PCV system, I have a very small negative pressure at the dip stick entrance, so that means the PCV system is working, right?

The weird thing about the shaking is that it doesn't occur during Reverse, but does in Drive. That seems pretty weird to me, and I wonder if it isn't a software issue. I mean, what kind of hardware issue would cause shaking while sitting in Drive, but not while in Reverse? Maybe something in the transmission? Anyway, I will call my dealer about a possible transmission/ETM software update.

I'm running out of ideas. Any ideas from you guys?

Thanks again,
Ryan

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Post by **MadeInJapan** » 30 Mar 2008, 23:08

Yes, your PCV is working properly!