Standardshift Diagnostic Team, here, STAT! (rev hangzorz)

Synchros shot? Weird noises while shifting? Not sure what needs to be replaced?
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comingbackdown
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Standardshift Diagnostic Team, here, STAT! (rev hangzorz)

Post by comingbackdown »

I need more ideas, guys. Toss out some ideas for me.

'92 Dakota Sport, 3.9L Magnum V6, 5MT, etc.

The rev-hang is TERRIBLE! I expected a bit in the cold, but... Under 60* = rev hang? Nuh-uh. No.

This is a commonly bitched about issue, however, only of a mildly annoying caliber, and much improved with a quickie mod.

That ain't it, though. If this thing rev-hangs any worse it's gonna turn into a Toyota.

Side note:
Not exactly the same in all areas, but I got a '95 shop manual in PDF format. Like, 30 frickin' PDF files.
1. Looking through a manual in PDF format is a bit of a pain.
2. These are direct scans from a manual. I have only one question. Why, why, WHY put fricking torque specs in a reassembly procedure but not at the BEGINNING OF THE SECTION you're working in. I had to sit here and read a good 25 pages just to get "Tighten to 350 inch pounds". Sheesh!

3. Fuel gauge is going to be fun, and not necessarily in the good way. I have the test procedure right in front of me...
But, it requires crawling up under the truck and hoping I can get the multimeter probes into the plug on the sending unit without having to dramatically lower my gas tank. Interior and under-hood junk for that is relatively mild.
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Re: Standardshift Diagnostic Team, here, STAT! (rev hangzorz)

Post by theholycow »

Is there a clutch switch you can try hacking for your rev hang?

I assume that "That ain't it, though." means that while rev hang is a known issue for your truck the known fix didn't work for you...is that correct?

Where did you get the PDF? Does the same source have collections of other manuals?

If you're going to do much work around the fuel tank, make it easy on yourself; remove the bed. Four or eight bolts, a couple plugs, and a buddy to lift one side of it is all you need to worry about. Piece of cake.
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comingbackdown
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Re: Standardshift Diagnostic Team, here, STAT! (rev hangzorz)

Post by comingbackdown »

theholycow wrote:Is there a clutch switch you can try hacking for your rev hang?
Sadly, the issues are under the hood on this one. I'm sure it probably has some form of dashpot, but there's no reason it should be anywhere near this bad. We're talking 1500 RPM 1st gear/clutch in/revs spike to 2000 and stay there/my usual clutch out in neutral... Here's where it gets dicey. By the time the revs begin to fall, the autotragic behind me is getting alarmingly close to making the rear end of my truck their hood ornament and then using the whole thing to give me an epic colonoscopy. (??? Spellcheck flagged the preceding medical term as an error. FAIL!) So, I just drop it into gear, ease up on the clut-CLUNK! It drags the RPM down now. Last time I had John in the passenger seat, he was talking, that happened, and I got " :shock: ... WTF did you do?"
theholycow wrote:I assume that "That ain't it, though." means that while rev hang is a known issue for your truck the known fix didn't work for you...is that correct?
It's a lot worse than your average case. There's a little tweaking can be done with the intake that has eliminated it for a few Dak owners.
theholycow wrote:Where did you get the PDF? Does the same source have collections of other manuals?
It was posted on the 2nd Gen Dakota section of a forum I was active on looooong and and have been back on since I got my truck. It was posted in their FAQ 1 (Common Issues. FAQ 2 is modding specific) along with about four cute little things I'm currently checking on, and another that I'm about dead sure is what's wrong with a friend of a friend's Dakota.
theholycow wrote:If you're going to do much work around the fuel tank, make it easy on yourself; remove the bed. Four or eight bolts, a couple plugs, and a buddy to lift one side of it is all you need to worry about. Piece of cake.
Add two more bolts... Very heavy eye bolts fastened to the bed... and the frame... That'll secure your cargo! Just make removing the bed a pain in the ass...
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Re: Standardshift Diagnostic Team, here, STAT! (rev hangzorz)

Post by IMBoring25 »

My '97 C1500 has a "stallsaver" that seems to have no purpose but instituting rev-hang if it counts a certain number of times that the revs get dropped below idle. Disconnecting the battery fixes it. Probably not your issue, but, for what it's worth...
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Re: Standardshift Diagnostic Team, here, STAT! (rev hangzorz)

Post by 1974Alfa5spd »

Lets see, 1992, pre-OBD2 and most certainly pre-DBW. Is it fuel injected or carbureted? Is the throttle easily accessible (IE on top of the engine?). I'd say manipulate the throttle bellcrank with your hand and see if it moves freely. If it feels stiff, look down the intake and see if the throttle plate is sticking open.
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Re: Standardshift Diagnostic Team, here, STAT! (rev hangzorz)

Post by comingbackdown »

1974Alfa5spd wrote:Lets see, 1992, pre-OBD2 and most certainly pre-DBW. Is it fuel injected or carbureted? Is the throttle easily accessible (IE on top of the engine?). I'd say manipulate the throttle bellcrank with your hand and see if it moves freely. If it feels stiff, look down the intake and see if the throttle plate is sticking open.
Multi-port injection. Throttle is right in front of your face when you open the hood. I might do this tomorrow, in and around finishing the stereo install.
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