850 Idle/RPM question

[bnzlva]

Let me start off by saying that you guys are awesome, without this sight many people including myself would be up a creek without a paddle. You guys have saved me gobs of money!

I had a question about my 95 850 n/a wagon w/ 142k miles vs. my 94 850 n/a sedan w/ 197k miles. The wagon idles at about 900-1000 RPM while the sedan idles at 400-500 RPM. At a 50mph cruise, the wagon is at 2000 rpm, the sedan is at 1400rpm. At a 70mph cruise the wagon is at 3000rpm, the sedan at 2500rpm.

Now, I know the throttle wire on my 90 740 can be adjusted by spinning the stop up or down, but the 850's throttle wire doesn't have that type of setup. Also, I am curious if the idle speed has anything to do with cruise speed as it seems to me in my limited auto knowledge that shift ratios/cruise rpms should be determined by the gearing and not the idler.
Finally, this may be attributed to a weight difference, but the sedan will blow the wagon off the road. The sedan just feels so much stronger off the line. I have a hard time believing that the wagon at 3342lbs can accelerate that much slower than the sedan at 3180lbs, a difference of 162lbs, or 1 avg adult.

My questions:
1. Is the difference in idle/cruise speeds causing the wagon to feel so sluggish?
2. Is the '95 wagon's idle/cruise speeds adjustable or will it make a difference?
3. Are there differences in the engines/transmissions from the '94 to the '95?

[Ozark Lee]

Check the zero position of the tach. Chances are that they are not the same. After I fixed my odometer gear I failed to re-zero the tach when I put it back together.

Mine now idles at zero RPM and my speedometer is off by 3 mph.

One of these days I will pull it apart again and re-zero the gauges.

...Lee

[Solutech]

My 96 850 sedan idles at a hair under 1000rpm . I think your rpm is out personally as at 70 mines about 3000rpm depending on the gear.

[bnzlva]

Check the zero position of the tach. Chances are that they are not the same. After I fixed my odometer gear I failed to re-zero the tach when I put it back together.

Mine now idles at zero RPM and my speedometer is off by 3 mph.

One of these days I will pull it apart again and re-zero the gauges.

...Lee

I had actually thought of that and they are both zeroed. Could they be geared slightly differently? Perhaps I should try cleaning a few components on the wagon, but where do I start in ways that might affect perfomance?

[Volgrrr]

Let me start off by saying that you guys are awesome, without this sight many people including myself would be up a creek without a paddle. You guys have saved me gobs of money!

I had a question about my 95 850 n/a wagon w/ 142k miles vs. my 94 850 n/a sedan w/ 197k miles. The wagon idles at about 900-1000 RPM while the sedan idles at 400-500 RPM. At a 50mph cruise, the wagon is at 2000 rpm, the sedan is at 1400rpm. At a 70mph cruise the wagon is at 3000rpm, the sedan at 2500rpm.

Now, I know the throttle wire on my 90 740 can be adjusted by spinning the stop up or down, but the 850's throttle wire doesn't have that type of setup. Also, I am curious if the idle speed has anything to do with cruise speed as it seems to me in my limited auto knowledge that shift ratios/cruise rpms should be determined by the gearing and not the idler.
Finally, this may be attributed to a weight difference, but the sedan will blow the wagon off the road. The sedan just feels so much stronger off the line. I have a hard time believing that the wagon at 3342lbs can accelerate that much slower than the sedan at 3180lbs, a difference of 162lbs, or 1 avg adult.

My questions:
1. Is the difference in idle/cruise speeds causing the wagon to feel so sluggish?
2. Is the '95 wagon's idle/cruise speeds adjustable or will it make a difference?
3. Are there differences in the engines/transmissions from the '94 to the '95?

800 r.p.m. n/a
850 r.p.m turbo

[bnzlva]

Check the zero position of the tach. Chances are that they are not the same. After I fixed my odometer gear I failed to re-zero the tach when I put it back together.

Mine now idles at zero RPM and my speedometer is off by 3 mph.

One of these days I will pull it apart again and re-zero the gauges.

...Lee

Lee, after contemplating your comment, I returned to the sedan and looked at the tach. Sure enough you were right. The needle is well below the "0" mark. I thought I had zeroed it in the past, but perhaps I didn't do it correctly. Any chance you could point me in the right direction in zeroing it?

[Ozark Lee]

The procedure is the same as the odometer gear repair except that you don't fix the gear.

https://www.matthewsvolvosite.com/odometer_fix.php

The trick is to get the indicator needles to line up on their respective zero positions as you put the face of the cluster back together.

...Lee