Engine/Transmission (1994 - 1998) Vibration , Miss , Or ?

[MarsHill]

Ha all, I am looking for some advice from the great TDR Wizards. I bought a 97 3500 auto with 119K recently and It has a vibration like a gasser cam, like bla-bla-bla-bla-bla at any RPM. It starts good, cold or hot, It smokes a little when cold but nothing unusual, runs very strong, and idles around 800 rpms in gear. It vibrates like a miss or maybe a bad harmonic balancer. My questions are, could this be the above mentioned or valves out of adj. or what? I also noticed a pretty good exhaust leak at #1 exhaust manifold. Sorry for the long post, any hints would be great. Thanks

 

[1dslram]

You most likely have a bad injector. Check the studs going thru the exhaust manifold, if they are bent towards the center of the engine, change the manifold before it breaks the ears off the head, a $3,000 fix. With the milage on your motor the manifold is likely the problem for the exhaust leak and injector is weak and popping off too early.

Bruce

 

[MarsHill]

Thanks, I have an ATS 3 piece in the mail. I thought about the injectors but figured it would run rougher if that was the problem. I guess its a good time to upgrade!

 

[Vaughn MacKenzie]

MarsHill, sure hope your miss problem is more easily solved than mine. Been fighting mine 14 months and 30,000 miles. Several different injectors & another pump, valve adjust, nearly complete fuel system parts replacement, new harmonic balancer, mostly to no avail. Next step is head removal. Piers fiddled with it and got it running better than it was but it's still not what it was when I bought it at 351k. It was silk smooth back then, not the thrashbucket it is now.



Mine is a slight miss at idle and uneven power delivery between cylinders, and quite a bit of vibration & thrashyness at higher RPM.



Hopefully yours is something simple like injectors, timing, delivery valves or governor springs. Miss problems are fairly common on 12-valves but luckily most are solved without too much headache.



Vaughn

 

[MarsHill]

Thanks Vaughn, you've got me worried know. Does your truck still run strong? I would think that if you had a miss that it would run weak or idle rough.

 

[Vaughn MacKenzie]

Sorry MarsHill, didn't mean to sound too negative. It's been a long story with my truck but chances are yours will be easier. Mine runs strong and gets decent mileage, so not all is bad. It kinda goes through phases too, the last couple of days it's been pretty smooth. Part of the problem too is I'm very particular with how my stuff runs, so unless it's nearly perfect I'm not happy.



You might try servicing your prefilter & heater though, that's cheap & fairly easy. Any leaks will let it suck air and potentially cause a miss. Also unplug your fuel heater and ohm it out. If it reads infinite resistance it's blown, fairly common problem. A fried heater usually leaks air.



Here is more info on servicing the prefilter http://dodgeram.org/tech/dsl/filter/pre-filt_clean.htm (check around this website, click Diesel Index link for lots of good stuff)



My thread about doing mine http://www.nwbombers.com/forum/index.php?showtopic=15869&hl=



Fleetguard Part number for preheater is 3907766-S http://dodgeram.org/tech/dsl/Facts/96specs.html

 

[MarsHill]

No problems friend, thanks for all the info. and I will definatley check the prefilter. I read your work on the fuel heater and may remove it all together, it doesn't get very cold here in the east

 

[Vaughn MacKenzie]

Yes I think you can just remove the heater puck and put the prefilter bowl back on. Not sure though.

 

[watkinsw]

rattle around glove box

I have had this rattle around the glove box and I can not find it. It sound like it is coming from behind the glove box. It is worse with higher speed. HELP!



97 dually with 115000 miles .

Andy