See if autozone will let you take a drive with one. Like a month or so ago I convinced them to let me install and drive off with a MAP sensor to see if it would solve my problem haha.

I've been looking into this some and while some of them are probably just ignition issues more and more points to the possibility of some being a PCM or transmission problem. Here'* one bit I found on thrashercharged.com talking about a 65-e shiftkit:

"Over the winter ('9, we've been working on this and determining the best and most cost effective way to address these issues. We've concluded that there is no easy way to modify the shift points or shift schedules / patterns, and modifying TCC lockup is not as simple as it was in previous years due to the introduction of the ECCC (Electronically Controlled Clutch Capacity) system, where the pressure plate does not fully lock to the torque convertor cover.
Instead, a special material is used in the clutch lining that allows a small amount of slippage to constantly occur, allowing the TCC to be ramped in and out slowly, reducing driveline torsional disturbances and eliminating TCC shudder or chuggle, two common complaints in the past. "

While it isn't specific it does say the "TCC shudder or chuggle" was a common complaint and that changes in the transmission eliminated it. This mounted with the other bits I think makes an issue outside the ignition plausible. Don't go throwing parts at it yet though, still much to be learned.

IF it is transmission related its called "TCC SHudder" and is common to a whole host of cars.

Some tidbits related:
http://www.sonnax.com/bulletins/tech/T3-EL-1197.pdf -- Mitsubishi has the same issue
http://www.specialtytrans.com/specia..._diagnosis.htm
http://www.shoupsauto.com/Tips.htm
http://www.shoupsauto.com/TipTCCShudder.htm
http://www.sonnax.com/bulletins/tech/TC-BW-599.pdf
http://www.talkaboutautos.com/group/...es/117106.html
"Master tech Chris Taurman wrote: "changing the fluid alone in 93-95 units is a short term fix; the TCM must also be flashed or replaced to prevent the fluid from becoming degraded again and to eliminate partial "EMCC" TCC operation which was the cause of 90% of TCC shudder complaints (NOT THE CONVERTER ITSELF!) as well as the aforementioned bump down (shift scheduling changes in the software took care of most of low mileage complaints).]"

Now to make sense of it all

can we get a translator?

thanks for looking into this dr. jay. i had no expert way of knowing that this was possibly a pcm issue, but it'* good to know that the possibility is being entertained now. when our olds 88 had problems, we went through 3 computers that left the car running rough and low on power every time. not same problem, but interestingly enough our mechanic finally figured out that there was an issue with the eprom on the computers his supplier was sending him. long story short, he notified the supplier, something (unknown to me) was changed in the prom, and the car ran buttery smooth afterwards. is this a similar issue? i'd be more than happy to be a guinea pig if you've got any ideas.

I know for a fact that there are software upgrades to enhance tranny performance.ie smoother shifts especially into overdrive. I read on the gm service site that tranny shift degredation is normal and can be fixed with a ecm reflash. New software is introduced almost daily.

I guess the only way to totally rule out the transmission would be to get a freshly rebuilt one. If the problem goes away then that was the problem. One of the links that DrJay put up is pretty informative about TCC slippage, and has alot of pics.

i think it might be a little bit cheaper to try a computer mod

I agree. Is there a way to modify the computer to always command 100% TCC apply in OD?

I'd have to agree

I found a webpage you can check for available updates. It goes off your vin number. I'm not sure if the website just isn't updated as much but the earliest 3.8 it supports is a '95. I'm awful sure it isn't complete as the first programmable pcm was in a '90 Geo Storm(owned by GM) and thats not listed on their page. I have heard of replacement proms, so this isn't to say there'* no help for us pre-95'*. I'm on the hunt for those now...

If you have a 95+ check out http://calid.gm.com and see if there'* an update. I ran a few through it and found updates for every one of them. If you decide to take it in to get it worked on know that because of a law the dealership ISN'T the only one with the capability to update it. Also, if the shop you take it to can do it don't let them charge you too much. It costs between $20-25 to get a 'one-day pass' to the GM information database and only a few mins to flash it. Try not to walk out with a $200 'upgrade'.

Again though, don't jump the gun and buy this just because its a different idea. Have it diagnosed first....Bumblebee tuna

bumblebee tuna?

ok amigos here is what I got:

Part Number Cal. ID# CVN Description
9365394 9365351 N/A CHANGE TO CORRECT 3-4 TRANSMISSION HARSH UPSHIFT AND ENHANCE POST O2 SENSOR DIAGNOSTICS.

BULLETIN 876520 16259374 16259017 N/A REDUCES THE POTENTIAL FOR INTAKE MANIFOLD OVER PRESSURE AND CORRECTS INACCURATE FUEL GAUGE.

BULLETIN 738325 16257624 16257550 N/A CORRECTS WRONG FUEL LEVEL CURVE INFO. IN CALIBRATION AND INTAKE MANIFOLD OVERPRESSURIZATION.

16253084 16252951 N/A SUPERCESSION - FIX FOR TROUBLE CODE P0121

16243694 16243608 N/A NEW CALIBRATION FOR IMPROVED SPEEDOMETER ACCURACY AND REDUCED POTENTIAL FOR SPARK TIMING ERRORS

16231394 16231308 N/A CONTROL MODULE CALIBRATION

sounds like I should take it in...~$25 is what you think it will cost?