Bouncy tach at startup

[...AndBoomGoesTheDynamite]

Hey everybody!
So im very new to this forum, but have had my 524 for about 2 years now. Just a few weeks back i had my transmission blowup on me which resulted in a $3000':shock:' rebuild. Now with a new tranny, everything in that area is fine. i am having one weird problem though...
Whenever i start the engine, the RPM starts at a lower-than-normal state then starts bouncing +/- 300 rpm from start up. It feels like the car is trying to keep its composure from shaking so much. About 3-4 sec later, it smooths out to a nice rumble. I don't believe that it has anything to do with the new tranny because just a few weeks before, it was the first time it ever did something like this. In fact, it was immediately after i changed the oil. The hiccuping was so bad that it stalled the engine.
Now, i am no where near mechanic status when it comes to fixing cars, but i can find my way around with a small push. So...
Any thoughts?

[altus22]

Have you checked your timing recently? Have you had your injectors pop tested? Have your nozzles been replaced recently?

[...AndBoomGoesTheDynamite]

Havent had any of them replaced or checked out, but ill definitely start looking them over.
any other thoughts would also be much appreciated!

ps...so a fuel problem such as a dirty filter would be out of the question?

[altus22]

I doubt the fuel filter is the problem, but if you haven't replaced it in the past couple years, I suggest it. Also, have you checked your glow plugs lately?

[...AndBoomGoesTheDynamite]

yea in the past 2 years the fuel filter hasn't been replaced. As for the glow plugs...i did have a suspicion.
Just a background...the car has 236600 miles on it = lots of checking. ';)' and with the first 200000 miles of it not knowing how its been treated = checks on top of the checks.

[Lincoln Turbodiesel]

If there is a lot of white smoke at start up and a strong smell of half burnt Diesel ...chances are you have one or more dead glow plugs.
When at Idle and it starts dancing around chances are you have a fuel delivery problem.
Why not start by...
-Check for leaks ..a leaky fitting .... cracked rubber fuel lines need to be replaced It can suck air into the system.
-Replacing the Fuel filter ....Fill it with diesel before screwing the new one back on. (change every 10,000 miles)
You may need to turn the key on and purge the air from the bleeder on top of the filter casting. The electric pump will pressurize the system before it gets to the high pressure injector pump.
-As for the glow plugs you can check for resistance ....but I found that checking each one on the bench is best. Apply 12 volts and see if they glow. Its good, or its bad. Some times they read good with a meter but fail under load.
Be very careful you can burn yourself.
PM me if you need help

[...AndBoomGoesTheDynamite]

UPDATE!

hey everybody...so ive had some time to mess with the car and even though i didn't get as far as i wanted i did note something interesting...
Instead of cycling the glow plugs just once, i did it 3x to make sure they got their work in (taking some added info from other threads advising this). Turns out...the bouncy rpm problem was much less severe, even nonexistent most of the time! It seems i have 1 or more bad glow plugs. On top of this future fix, im also going to see if i can get a hold of some new injector cores. That way ill know for sure.
Let me know your thoughts!



--alex