Pace is off ok track run mode

IMHO it is laying on a big averaging base at a displayed pace. It is no instant pace (it was silently removed 2 years ago) that you see on a watch screen. It is a rolling average with a base of 20-30 seconds - if you walk before your interval, your walking pace will be counted to your displayed result. The shorter the interval is, the greater the error.

And the the only solution for me was to buy a stryd. Now i have a 3 sec rolling pace and the world is OK again 

There are also standard foot pods. They have gone out of fashion a bit, so can be hard to find new, but used ones can be found on selling platforms.

A standard ANT+ foot pod is reportedly less accurate than a Stryd.

For standard foot pods: your watch will auto-calibrate a foot pod in the first kilometer of running and then sets a calibration factor that you can see in device settings -> sensors. Out of the box this is 1.00. To calibrate it correctly, doing a track run activity at your interval speed for 3 laps will probably work well. But if you do a warm-up slow run > 1 km before you start intervals, the correction factor will be set for the slow run, so it is best to set the sensor to Off in device settings during warm-up.

Which is cumbersome and error prone and Stryds are probably smarter in handling changes in pace. So the standard foot pod is a budget friendly but cumbersome option.

I do my intervals on a track every week at my athletics club. GPS doesn't work very well on a track, so just ignore that.

You know the distance you have to run (because you are on a track) and you probably know the times you have to hit for that interval. All you really need for interval training on a track is a stopwatch. 

It's nice to see how you have done, but for me it's easy to see which intervals I ran. I don't mind if I did a 600 meter interval and garmin reports it as 630. Don't look at pace, just look at the time of the interval.

Just focus on the efficiency of your training and not how it looks on garmin connect/strava. 

Elbo said:

All you really need for interval training on a track is a stopwatch.

Yes.

And you will learn how the different pace feels - but of course it would help learning though, if the Forerunner would show it correctly, I get the Threadstarter here.

Elbo said:

I don't mind if I did a 600 meter interval and garmin reports it as 630.

Well, I have not been on the track often, but last time was a 12 rounds run in a company event.

I had to go and the watch did not even have a lot of time to get a fix after I started the track run mode. I started a little before crossing the start line and stopped a little later after the 12 rounds.
During the run, I had to overtake several times and change to track 2 for that.

In the end, my Forerunner showed 4830 Meters - which I think, is pretty accurate. So my impression is, the distance that track run activity produces is not so bad.

Also I thought, the pacing shown during run was ok, but of course I ran a steady pace and no intervals. Might be different with short, fast intervals because of the smoothing (like global_local wrote).

Thanks for all your responses. Im guessing ill stick to lap times then. It will just take some time getting used to it. i was just really frustrated because i didnt know which times were correct and which were not even tough that isnt so hard to find out by just using a stopwatch or the lap time feature, ill admit that. One last question tough, is the current pace that is shown on track mode gps based or is that just your watch doing the math because that was my main concern all the way. I just couldnt understand why a modern sports watch wouldnt geh the pacing right on an exactly 400m long track cause all it has to do really is just calculate your current pace by metres done in x amount of time, no gps needed or am i wrong on that? Thanks for clarifying.

All the calculations are GPS and time based.

Relying on the internal accelerometer will be less accurate overall because each person moves differently at each pace. 

Knowing the time you should take for the distance is the best way to avoid messing up your intervals while running on a track. 

I understand your frustration because I was there a few years back with my first GPS watch.

However, every GPS measurement contains an error, which varies depending on several environmental factors, such as clouds, trees, and buildings around the track. 

This is why sometimes the watch shows a few meters more than 400m each lap. Or keeps adding distance while doing stopped rests.