1997 Eclipse 420A N/T won't rev up/transmission

[Krayth]

I've been fighting with this car trying to get it to run off and on for the last year (see http://www.dsmtuners.com/forums/maintenance-repairs/415907-no-start-no-spark-1-4-coil.html). Finally got it fixed so it would start a week ago. So now I get to see what else is wrong with it. The two major issues right now are the misfires and the noises from the transmission.

First the misfires:
The car starts and runs "fine" as long as you keep the tach down. It seems to idle/run a little rough (to me) but that's ok. Here's a video of it idling when it's "cold" which is 97 degrees outside:
Idle walk around

It does smooth out a little bit when it's warmer.
But when I try to rev the engine up it'll choke/sputter/misfire around 2500 RPM, or closer to 3000 when hot. it does this despite gear, parked or moving.
Misfires

Again not the best audio, it sounds less healthy in person. At the time of that video there were no trouble codes in the computer. Later that day I took it for a longer drive down a back road. All was well as long as the engine was below 3k. Then I tried to accelerate in 5th gear to the limit, it sputtered as usual but this time the CEL came on. When we got home I plugged in the scan tool to get the codes:

Trouble Code:
P0300 (Random/Multiple cylinder misfire)
Pending Codes:
p0301 (Cylinder 1 misfire)
p0303 (cylinder 3 misfire)
p0304 (cylinder 4 misfire)

Here are a couple videos I took today trying to rev it up, audio is bad, but it was misfiring around 2800 after warming up at that time
Misfire 1
Misfire 2

After these videos and messing with it, I checked the codes again. This time I got
p0300, p0302, p0303, and p0449 (EVAP leak, small)

The common feeling around here is that it's the computer doing it, but we don't know why. Below 2500 it runs steady and pulls strong. Issues with sensors? is a small EVAP system leak enough to do it?

ISSUE 2: Transmission

At around 22-2500 RPM when cold the transmission makes a squealing/vibrating sound, sounds like a dry bearing maybe?
worn bearing?
Could also be heard in the rev up videos above.

Note that this video was taken with the on a jack with the wheel off and the noise would sound while idling and would go away when the clutch is pushed in. With the car on it's wheels it will only make the sound when the engine is spun up to ~2500 rpm. Makes the sound when in neutral or when driving, spins down with the clutch in. Also it does go away when the car warms up to operating temp, at least we don't hear it anywhere in as high as we can rev it due to above issue.

So guys, any ideas/help/advice anyone might have would be very, very appreciated. The car is fine for driving around town, but I'd like to be able to take it out on the freeway for the work commute which was the original intention...

Thanks

 

[Krayth]

twice now when driving hard to force the car to sputter It's generated the trouble code for "Intermittent CMP/CKP sensor signal loss" but it doesn't get this code all the time when it misfires. I know the sensors are good but I'm not sure how to go about testing the circuit when they share common feeds.

 

[1996Eclipse420a]

First of all pull your plug wires, take out spark plugs, and see what kind of shape they're in.

It's throwing those codes for a reason, but just in case, check the coil and see how it looks.

Now as for the transmission, I've had problems with 2 of them. Jumping out of gear and everything. I've finally found one that's in good shape, but by all means, I'm not a transmission specialist.

If all else fails, then try finding a ECU off of another one, and see how it works... unless you want to buy a new one.

as far as the noise the transmission is making, it could be bad bearing. also, when you hold down the clutch, does the noise go away? if so then it could be the throw out bearing, but I don't think that's the case.

 

[DSM1G90]

Squealing really points to the TO bearing.

Clutch adjustment needed, or do you 'ride' the clutch pedal instead of taking the foot off the clutch between gears? If it is the first, you're killing the TO bearing to death.

-DSM

 

[ChipmunkRox]

I am having the same issue with my 95 NT i just replaced the pcm cmp and ckp and when i did all of that the car is running better and also the noise you hear coming from the transmission is the throwout bearing so you might want to replaced it soon before you have worse damage done

 

[Krayth]

Time to update this old thread.
I figured out the misfire issue last fall. It turned out to be the NEW crank sensor. I think it a perfect fit or something else about it wasn't just right. I spent some time testing the 3 sensors I had in a box and they seemed to work correctly/were putting out the right voltage at the right positions. When I put the original one back in and and started it up it worked just fine. So that was that, now it's just the transmission.

This last weekend I got it pulled off the car and cracked open. Nothing I can see/get to without pressing the shafts out appears to be what is causing the noise. Throwout bearing feels smooth.

Here are some use cases:
When the car is cool/sat for a while it will make the noise idling in neutral with the clutch out. If I press the clutch pedal in, the noise slows to a stop.

If the car is being driven while cold until it spins long and fast enough to presumably get fluid where it needs it. So about 1/2 mile.

If the car is in motion and in gear and I press the clutch pedal in so the car is coasting it will continue to make the noise.

Car in motion, coasting, in neutral, clutch out = noise

Car in motion, coasting, in neutral, clutch in = no noise


Hope that wasn't too confusing. It was my understanding that the throwout bearing making noise doesn't fit all those cases, but I may be wrong...

Please let me know what you think, thanks.

 

[Krayth]

So a while after my last post, someone pointed me to this thread:
2GN.ORG :: View topic - According to chrysler, this is normal and OK!

Which has a lot of information about my transmission (NV-T350/A578) and the consensus on the sounds I hear is that it's the synchronizers just do that after they have worn some... thanks Chrysler! And that even if you replace the scynchros they will eventually wear and start making the noise too. One person claimed something like 230k miles on the same transmission after it started making the sound and it still works fine.

Since I hadn't bought a press yet and was hesitant to actually tear into the shafts since the tranny functions great, I decided to try the recommendation of a different fluid. So I cleaned what I could, put the whole thing back together and in the car, then poured in about 2.4 qt, of Amsoil Manual Transmission Synchromesh Fluid, since someone also suggested putting in slightly more than the amount that the manual calls for, about 2.1.

Started the car and let it idle away... not a squeal to be heard! Now it's warm afternoon so I don't know what will happen when I start it on a cold morning, but it's better than it was. I'll update this post at some point after I've driven the car a bit and seen how it performs... fingers crossed.