Gas and Oil Home Heating Furnaces - Is the repair man trying to take me on a Tempstar 5000

I bought my home 2 years ago and I had a home inspection. the inspector said my furnace was only a few years old (and it looked it).
I just found out that it is a 1992 model inter-City products (now INternational Comfort Products of Tennessee)

last year we noticed that the heat (fan) would kick on and go off repeatedly. I knew there was something wrong so we just burned more wood as it was late in the season.
all summer the AC worked fine.
If I recall correctly the fire would spark up with no problem then the whole thing would kick off then start again every 30 seconds or so.
I remembered our problem so I let myself be tricked into a $125 (that turned into a $280) tune-up and furnace cleaning. When I told the service man about the issue he came back with: "furnace need new ignition mod + fan d limit".

I had a feeling that the fan limiter was the issue for research last spring, but never saw anything that pointed to the Ignition Module.

so....
is the guy trying to take me?
SHould I try to do the replacements myself?
If i have them do it what should they charge?
Should I replace the fan limiter first then the ignition Module?

I can do anything I have a manual for or that works by common sense. I can troubleshoot to a point.

my furnace name and model number has offered little help and I am getting many mixed messages on the two recommended replacements parts.

furnace is:
Tempstar 5000 high efficiency furnace
NUGE125ak01
867.768400
L922237697

ignition module is:
honeywell S8600M (i believe it was replaced by the S8610)

Fan Limiter is:
honeywell
hq1005596HW
L4046E(or B not sure)2213 6 9209p

It seems the industry is trying to keep this stuff as mysterious as possible so we will have to higher "professionals".
but you guys seem to know what you are talking about.

Any help is appreciated, of course.
thanks

If the furnace lights and then goes out it is far more likely that the flame sensor is not reading the flame than any problem with the ignition module. That is assuming that the ignition module is not also part of the flame sensing circuitry.

Can you determine which burner lights first? The flame from this burner will follow a "runner" or "cross ignition" channel to light the other burners. The last burner should have a "flame rod" mounted to hold the rod in the flame. The rod is about 1/8 inch in diameter and will have a single wire connected to it. There will be one or two screws holding the rod in place. Remove the rod and polish it with a ScotchBrite pad and then replace it. Make sure the wire is securely connected to the flame rod.

If this doesn't make any sense you may not have a flame rod but some other kind of flame sensor. If at all possible take some pictures of the furnace, especially of the burner chamber, and post them. The guys that deal with this all the time all have day jobs and they are pretty busy now so you might not get a response until late Monday night.

To post pictures you need to first upload the pictures to a photo hosting site such as photobucket.com or villagephotos.com. and then post the public URLs for the pictures (or album) here. More pictures are always better than fewer. Please have CLEAR pictures and have both close up pictures and ones from a far enough distance that we can see how the various parts are interconnected.

thanks for the tips

I will work on pictures tomorrow

It appears that when I put the heat on the sparker goes, the pilot light lights the burners all kick on. they stay on for 30-45 second as the small fan spins, the main blower kicks on and after 10 seconds the burners go out. immediately after the burners go out they kick back on for 10 seconds. this continues for 1-3 minutes the the blower goes off. the flame kicks back on and after 30 seconds the blower goes back on. the flame goes back into the 10 second on restart thing and every 30-60 seconds the blower goes off.
very annoying and I am concerned that it is going to burn out something. I am turning it off tonight for sure until I can get further info.
obviously this kind of stuff keeps me up at night.
thanks

thanks for the tips

I will work on pictures tomorrow

It appears that when I put the heat on the sparker goes, the pilot light lights the burners all kick on. they stay on for 30-45 second as the small fan spins, the main blower kicks on and after 10 seconds the burners go out. immediately after the burners go out they kick back on for 10 seconds. this continues for 1-3 minutes the the blower goes off. the flame kicks back on and after 30 seconds the blower goes back on. the flame goes back into the 10 second on restart thing and every 30-60 seconds the blower goes off.
very annoying and I am concerned that it is going to burn out something. I am turning it off tonight for sure until I can get further info.
obviously this kind of stuff keeps me up at night.
thanks

After reading this post I am pretty sure the problem is in the control module. If it was just the blower having problems, I would say a senor was bad, but because both the burner and blower are cycling, I am saying the control module.

***NOTE***
One thing to check ground on the module. I had one act very similar once and all it needed was a ground wire attached. These controls are very sensitive.

ground looks solid
any tests I can do to see if the ignition module is faulty, or just replace it?

I have had a bad feeling about the fan limit control for a long time any thoughts on that or just replace the ignition mod and go from there?

any recommendations of where to buy my parts?

Does the small fan also go out right when the flame goes out?

Trying to find out if faulty thermostat is causing problem. You can easily test to see if you are losing 24 volts to W terminal on block.

Yes, it can be the board, but you need to rule out any other possibility.

small fan keep spinning
checked the thermostat last winter and there was no problems there.