Hey guys,
Havin a few problems with my 96 Dakota 3.9 5speed with 128,000mi on it. Ok first problem is the idle, it surges up and down while idling. The tach sometimes says its idling at 200 other times at 600 but it pretty much moves all over the place with-in that range. Sometimes the idle will drop really quickly and I hear the timing chain rattle a bunch and then it comes back up (yes i have normal infamous timing chain rattle, but it rattles a heck of a lot more when the idle drops like that) and when it drops the whole truck shudders and the engine is shaking with maybe 1 or 2 very soft pops out of the exhaust. It does this cold and hot. I felt the IAC when the motor was running and it moves but very jerkily. I am thinking it is the IAC or the TPS but each of those cost almost $50 and right now I can only afford one.So I am hoping someone might be able to shed some insight into which one I should get right now that might help this.

Next problem. When accelerating I hear sound like "tss tss tss tss" that moves with the engine speed. I been thinking it might just be the sound the injectors make but it's sort've loud to be injectors. It only makes this sound when acceling and not when idleing or reving the engine. Only when there is a load on the engine. Any ideas on what might be making the sound?

Yet a third problem. Well, maybe a prob. This is my first dakota and I have only owned it about a year. i put a flowmaster exaust on it. Pulled the throttle body, cleaned all of it. Took my dremel on a boring afternoon and polished the bowls and underside to a mirror like shine. Moved the intake air temp sensor to the very end of the metal air filter assembly. K&N air filter of course. Basically did all the tricks to get as much free HP and TQ and possible without pulling my whole intake and attacking it with the dremel (haha...you know there will be other boring afternoons to have fun with that one) So the problem is the accel seems kinda slow until I hit 3000rpm. After 3000 it is incredible. When on the highway doing about 65 I can drop it into 4th or if I feel like really abusing it 3rd and I am at 80 in about a second. Hit 100 in about 3 secs. So passing is incredible. but it is just off the line performance that I feel like is lack beyond what it should be. Is everyone elses truck like that or have I got an issue?

I go over this engine practically every day looking for vacuum leaks or anything else that I might see as an issue. (Being a mechanic I am a little obsessed about it) Any advice is greatly appreciated

 

My truck is the same way. Low end power is nothing, but i also have an auto. so mine is probably worse. The noise may be from the k&n, when i put mine in i could really hear the air sucking in. My truck is really loud when it is cold, like in the morning. Well i hope that helps.

 

Hey Bad96, I just wanna know how the hell you got your 3.9 V6 to do a wicked burnout like that. I got a 95 and there is NO way I could do that, not even in a reverse drop, which I dare not try.

Sorry corvair, I got no advice for ya.

 

my 88 will do a burnout like that 3 rearends later and it still does em.


but my timming chain israttling and needs replacing really bad. and I have no power until after 3000rpm. it boggs down and spits and sputters below that. but after 3000 its good and has lots of power. so I would try replacing that.

 

try cleaning your throttle body, if it's dirty it will cause the truck not to idle right.

 

Well, upon pulling my spark plugs that I replaced about 8 months ago I found that ALL of them were fouled. So I started looking at my fuel system. PSI is within spec for the pump. I read randomly that the connectors for the fuel injectors can get dirty and cause a prob. I pulled each injector, sanded the elec. connectors, cleaned out the plugs for the injectors, and replaced my spark plugs. Back up to 18mpg now, but still having this rough Idle issue. The tach says I am idling at around 300-400 RPM. And I am still hearing a slight 'whump' out of the exhaust every few secs when Idling. So thistiming chain rattling issue that these trucks seems to have, is it constant when idling or is it a every now and then thing? Mine is constantly rattling when idling. I find it hard to believe is the timing chain because of how nice it runs when not idling, but you never know. I also installed a Flowmaster exhaust. Could the engine not be getting warm enough now? When I start it cold it seems to idle perfect till it warms up. The temp gauge reads a bit less than halfway. Then again it could be the Hall effect sensor or even the crank sensor.....this is starting to get expensive.
Also think I found what that 'tss tss tss' when I am accelerating is.I noticed a exhaust manifold bolt (near cyl 3) has been broken off in the block. Dont see any signs of a leak but I am fairly sure there is one
I appreciate ya'lls advice

 

 

My tach is a little off at idle too. The timing chain could cause it to idle funny because there is not as much tension on it at lower rpms, when you give it gas it should be getting tighter. Mine ran alot better after i changed it out!!!

 

o yea, and that is just a brake stand! It does them really easy, and if you know how to work the brakes right it does not really where on them, my back ones have been on there for about 20,000 miles of burnouts and still work, just dont press them so hard. i had both tires spinning at somwhere over 110 yesterday in the rain, it bottomed out the spedo and kept going so i backed off of it. You cany hurt these trucks!!!! lol.

 

You can certainly hurt the automatictransmissions, though.
I did my second transmission fluid change (wasn't able to add my trans cooler yet, because the plumbing fitting on the output of the radiator is a non-typical thread size [:@], probably AN size, which I should have thought of before hand ), and again, found another big metal piece (see picture, not quite as big this time) and two smaller ones. Showed it to my grandpa and (besides the face that said: that things gonna die sometime, kid) he said it looks like a thrust washer. My transmission does not like, not one bit, me jumping on the throttle, as it will shudder the truck a few times (especially bad when the truck is faced up hill) and finally go.
I definitly foresee a better built transmission in my future.