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James Anderson (Jnjander)
Member
Username: Jnjander

Post Number: 60
Registered: 08-2003
Posted on Thursday, April 08, 2004 - 09:42 am:   Edit Post Delete Post Print Post

At times when trying to accelerate from a dead stop, my truck (99DII) hesitates and sputters. It happens when it's cold and when it's warmed up(so all the time). It's like the transmission and the engine can't decide how to work together. I can hear the engine revving but it doesn't seem to go any faster. Then all of a sudden, I can feel everything working together properly and it accelerates better.
It's really irritating not to mention dangerous because our neighborhood is directly off a busy highway (GA-400) so you always have to pull into traffic where everyone is going 70-80mph. I know disco's are not speed machines, and that's not what I am looking for, it is just that is has not always done this so I am trying to get it figured out.
I ran seafoam thru it a few days ago, hoping it was something simple, but no luck there. Cold it be the MAF? I've heard that if it is sending the wrong signal to the transmission that it does not choose the correct gear to be in. Thanks.
 

Kyle Van Tassel (Kyle)
Moderator
Username: Kyle

Post Number: 949
Registered: 11-2002
Posted on Thursday, April 08, 2004 - 11:45 am:   Edit Post Delete Post Print Post

Sounds like what you are describing is a poor running truck and the clutch fan pulling it down when its cold....
 

James Anderson (Jnjander)
Member
Username: Jnjander

Post Number: 61
Registered: 08-2003
Posted on Thursday, April 08, 2004 - 11:53 am:   Edit Post Delete Post Print Post

It happens even when it's warm though...
To solve the poor running problem, I have changed the plugs and air filter and am planning to change:
plug wires
O2 sensors (running lean codes but they have been there longer than the new problem)
perhaps the MAF...

What else?
 

Matt Cooper (Coops)
New Member
Username: Coops

Post Number: 5
Registered: 04-2004
Posted on Thursday, April 08, 2004 - 01:15 pm:   Edit Post Delete Post Print Post

"Engine revs but no speed is gained"

I used to drive the old military Defenders with the 2.5 non-turbo diesel and they were a bit like that. Didn't matter how much you stamped on the accelerator, all you got was "Variable noise, constant speed."
 

Kyle Van Tassel (Kyle)
Moderator
Username: Kyle

Post Number: 950
Registered: 11-2002
Posted on Thursday, April 08, 2004 - 01:31 pm:   Edit Post Delete Post Print Post

When ever the fluid gathers at the bottom of the clutch housing (Engine turned off) the truck will start out that way. Then you will hear the fan stop which sounds like the engine drops in RPM to some...
 

James Anderson (Jnjander)
Member
Username: Jnjander

Post Number: 62
Registered: 08-2003
Posted on Thursday, April 08, 2004 - 01:44 pm:   Edit Post Delete Post Print Post

I noticed it still doing it after driving 25 hwy miles this morning...efter exiting and coming to a light, it was still acting up when I accelerated when the light turned. I guess that makes me lean more towards it just needing a good tune up. Not that it couldn't be more than one thing though...
 

Chris Browne (Chris_browne)
Senior Member
Username: Chris_browne

Post Number: 741
Registered: 02-2003
Posted on Thursday, April 08, 2004 - 02:02 pm:   Edit Post Delete Post Print Post

Transmission trouble will be my estimate. How many miles on transmission? How many miles since you last drained fluid, replaced filter?
 

James Anderson (Jnjander)
Member
Username: Jnjander

Post Number: 63
Registered: 08-2003
Posted on Thursday, April 08, 2004 - 02:05 pm:   Edit Post Delete Post Print Post

74K on the transmission. I changed the fluid and rinsed the filter about 5,000 miles ago.
 

S.C.Young (Youngsc)
Member
Username: Youngsc

Post Number: 64
Registered: 10-2003
Posted on Thursday, April 08, 2004 - 02:10 pm:   Edit Post Delete Post Print Post

pardon my public school reading comprehension- but RPM increases and speed doesn't? That's slipping in the drivetrain (trans/torque converter)
 

Kyle Van Tassel (Kyle)
Moderator
Username: Kyle

Post Number: 951
Registered: 11-2002
Posted on Thursday, April 08, 2004 - 02:29 pm:   Edit Post Delete Post Print Post

James , thats why I said originally that it was a poor running truck and its being magnified by the fan clutch. Unless you want to hear that its the trans , thats the only thing that will make it apear as if its revving hard and not going anywhere.
 

James Anderson (Jnjander)
Member
Username: Jnjander

Post Number: 64
Registered: 08-2003
Posted on Thursday, April 08, 2004 - 02:40 pm:   Edit Post Delete Post Print Post

Thanks Kyle. I REALLY don't want it to be the trans. I am going to try to cure it from running poorly and see what happens from there. I saw and earlier post on checking the fan clutch, I'll check it too.
 

Chris Browne (Chris_browne)
Senior Member
Username: Chris_browne

Post Number: 742
Registered: 02-2003
Posted on Thursday, April 08, 2004 - 03:25 pm:   Edit Post Delete Post Print Post

Kyle,
Being in the wrong gear would also give James the same experience. If he was in second or third, it would pull weakly from a stopped position despite revving. I assume the regular 30k changes were done. Only ever heard of replacing filter, gaskets not flushing. Dirt in the valve body would cause incorrect gear to be selected.

 

James Anderson (Jnjander)
Member
Username: Jnjander

Post Number: 65
Registered: 08-2003
Posted on Thursday, April 08, 2004 - 03:27 pm:   Edit Post Delete Post Print Post

I paid better attention on the way home to the RPM's and stuff...what I noticed was that as I accelerated, it was the engine that seemed to stutter and prevent acceleration. It would get to about 3500 RPM and then the acceleration stopped (the RPM's held at 3,500) and it felt like it was missing. Maybe the plug wires are bad?
 

Kyle Van Tassel (Kyle)
Moderator
Username: Kyle

Post Number: 953
Registered: 11-2002
Posted on Thursday, April 08, 2004 - 03:33 pm:   Edit Post Delete Post Print Post

A miss could be caused by alot of things. PLugs and wires would be a good place to start.
 

S.C.Young (Youngsc)
Member
Username: Youngsc

Post Number: 68
Registered: 10-2003
Posted on Thursday, April 08, 2004 - 04:07 pm:   Edit Post Delete Post Print Post

You just opened the floodgates of speculation. Same exact symptoms of a Heep I had when the catalytic converter clogged.
Do the usual tuneup stuff related to the ignition- check the wires with a meter, cap, rotor etc.
 

James Anderson (Jnjander)
Member
Username: Jnjander

Post Number: 66
Registered: 08-2003
Posted on Thursday, April 08, 2004 - 04:12 pm:   Edit Post Delete Post Print Post

Thanks guys, I have recently done plugs and air filter, will move on to the rest of the tune up stuff.
 

S.C.Young (Youngsc)
Member
Username: Youngsc

Post Number: 71
Registered: 10-2003
Posted on Thursday, April 08, 2004 - 04:21 pm:   Edit Post Delete Post Print Post

My 95 ran like crap and had a BAD stutter when cold. Fixed it by:
replaced cap and rotor- were probably 3 years old
replaced plugs- probably older than the cap
cleaned MAF carefully
cleaned TPS carefully
replaced PCV "T"
kerosene douche in the oil
seafoam in the intake plenum (most noticable improvement)
two tanks of fuel with Techron

After all that, it runs like brand new- no s**t!
 

James Anderson (Jnjander)
Member
Username: Jnjander

Post Number: 67
Registered: 08-2003
Posted on Saturday, April 10, 2004 - 12:19 am:   Edit Post Delete Post Print Post

Just as a note, I replaced the MAF today and now it runs like a scalded dog. Well....maybe a three legged scalded dog. That seems to have been the big problem.

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