Transmission failing?

I finally got the replacement engine in my 97 and got to drive it. I never really got to drive the car because of the rod knock. I changed the tranny fluid and drained the torque converter because the engine was out and I was able to get to it. Local driving it seems fine, shifts ok. If I accelerate quickly, like getting on the highway, the car feels like it stubles and slips, it feels like you ahve to let off the gas to get it to shift. The old fluid looked original and smelled bad, but there wan nothing alarming in the pan, just the usual metal slime on the magnet. Is my trans on its way out, or could a solenoid be going?

It's very possible that some clutches are slipping, but my first impression of your problem - I would more likely suspect a misfire due to plugs and wires because you are describing a stumble first.

Did it work poorly right away or after some miles?

Smooth type of slipping or ignition "rhythmic" chattering?

Pressure solenoid bad?

Are the ignition wires new?

well, when I say stumbles, I mean it feels like it doesnt know what gear it wants to be in. Sorry for the confusion.The engine is smooth and it doesnt throw a code. Once I get up to speed the car cruises nice, but getting there can be rough.

Understand, but you said the trans shifts fine in local driving, and at cruising. This suggests the problem is occurring under load (boost). Seems ignition related to me. The spark voltage is much lower when not in boost, so may not cause any problem until you really get on it. You will usually not throw a code with this type of misfire.

One way to tell is to remove the SC belt and carefully tie it off to the side (be careful to clear the crank pulley). If your problem goes away, it is likely ignition related, not the transmission.

I'll have ti try that. It was misfiring and threw a code, but I had less than a gallon of 1+ year old gas in the tank. That seemed to stop after I filled it up with 93. I replaced the plugs on the new engine, but didnt do the wires yet.
EDIT: I just actually thought of something. The old engine was throwing a cylinder 3 misfire (which this one did once I got it out on the road for the first time). I thought the misfire was caused by the knock (somehow), and figured with the new engine it could be the low gas, but I just realized I swapped the coil pack/ICM to the new engine because it was attached the the tensioner I had to swap. So theres a good chance either my ICM or a coil could be going, the wires on this engine came with it.

When my wires failed at a little over 100k miles, they still looked almost new. I thought for sure it was the transmission - I think I even called Ed Morad about finding a replacement. Car drove fine when not in boost. I took the car to INTENSE and we took the SC belt off to see if it was ignition related. Sure enough, the car shifted fine. New wires and that transmission shifted perfectly for another 50k miles.

I think you guys are right. I took it out for lunch and opened up on it. It started stumbling again and the CEL came on. I had my scanner with me and cyl 3 is missing again. Off to the parts store after work, get some delco wires.

I don't know if we're right, but I'm glad you're at least looking into the wires as a possibility. I'd rather be wrong about that than see you take out the transmission! Even if it's not the wires, you probably could use a new set anyway if they have more than 50k miles.

Coil packs can fail, but usually are robust if you keep plugs and wires maintained. I'm still running OEM coils with 197k miles.

the engine I got for the car has 60k on it, and the plugs were original. I replaced those while the engine was out. If it does end up being a coil as well I have some spares now. Thanks for the suggestions!

UPDATE: OK Guys. I went and replaced the wires to no avail, same problem. I dug out my spare coils from the engine swap and replaced the suspect one. I now have full power, no hesitation, and my transmission is "fixed"! Thanks for the tips, glad to see it was a cheap fix.

I think you just helped me figure out my car's problem. What you just described is identical to what my car is doing except with cylinder #4. The previous owner told me that the transmission is bad and I got a killer deal on the car but now I don't think its the transmisson at all.

Offer to buy some new coils, wires and plugs. Probably needs them anyway.

Hold off on the coils until you see what plugs and wires will do for you!

Sounds good. I'll swap those out first and go from there.

If I remember one of my other cars had cracks in the wires and they were arching/grounding. New set of wires and all was good.

Thanks again.

On these cars you don't or won't necessarily see a problem with the wires before you start to experience problems.
As a matter of fact almost everyone that has experienced problems and finally determined it to be the ignition wires showed no external defects or arcing under the moonlight when damp.
They fail internally where the current carrying capacity has eroded and can longer handle the necessary current while under boost.
It can be real difficult to convince some people to change wires when they can't see a problem with anyone of them.
It's usually after they have spent a bunch of money on other things that didn't fix the problem that they finally relent and solve the problem for about $50.00 including spark plugs.
It is possible to have a bad coil but usually they only go bad after the car has been run a long time with a bad wire and/or plug. The coil will strain to put out enough juice to overcome the bad wire and fail.
Also you can go 2 routes with wires, either buy the AC Delco wire set for about $35.00, which will last a long time or go with specific more expensive wirres such as Magnecor or Taylor. Don't get caught up in the hype surrounding the Accels and MSD's, etc. They can continue to cause you problems and you'll be scratching your head trying to find the problem "because I just changed the wires, that can't be the problem anymore" well it can be. Also, just get the wire sets that are already made up to fit the car. If you get the universal set and have to crimp the connections yourself you are just asking for future problems. Just my opinion.

Good Luck and Welcome

BTW, Vinnie what year car do you have and is it Supercharged.
If you fill out your signature with some of this info it will help us help you.
Just go to the FAQ tab at the top of the page and find the question that will answer how to do it.
Thanks

Nicely explained, Rick. I'd say based on his experience with the wires causing such a ruckus under acceleration, he's got a supercharged Riv.

First, Thanks and........
I assumed the same as well. But I thought if he's going to hang around for a while a Sig would be a good idea.

Rickw wrote:

If you get the universal set and have to crimp the connections yourself you are just asking for future problems.

On that I'll disagree, but it all depends on the quality of the crimp. I have some experience in this, I've made many sets including the set on my 3800, and I still have a set of Taylor 8mm wires I made nearly 20 years old that are still in excellent condition. There are a few nicities to making your own:

1) you can use Taylor wires, an excellent quality wire
2) you make the lengths exactly what you want them to be, perfect for any engine with upper external mods or you want to appear nice.
3) Taylor has some nice wire looms too, that screw together and look great.
4) Some pride in your work!

However, for most people I recommend just getting the AC Delco wires. They are close to the right length, good quality and will last a long time. Keep in mind that AC Delco wires will not be identical to the OEM wires, you can't get the numbered 'Packard' wires that I know of, you know the original ones that lasted 14 years?

The Packard's are only available if you stumble across some NOS off Ebay or something.
But even the replacement AC Delco's don't last like the wires that came originally on the car.
I agree with you on that. My experience on GM's is that OE wires will last an extraordinary long time provided that they haven't been removed and installed a lot of times and they were not subject to oil leaking on them, etc.
But once you have to replace that first set it's never the same unless of course you get a quality aftermarket wire.
I only recommended not to get the cut your own because most people do not have the experience with doing it properly and if the engine is stock and doesn't require wires any longer than stock then I recommend pre-cut and pre-made to fit wires.
Even still, no matter how much experience you have with them you can never get as good a crimp as a manufacturer's crimp without the $300.00 crimping tool.
That's just my opinion, although i have made my own wires on one of my bikes right now (and in the past on many others) due to the custom nature of coil placement and dual plugged cylinders.
They work fine. But would still like to have access to a $300.00 crimper.

Hey guys, I know its an old thread but I am afraid that the thread title may apply... So my 96 Riv has about 380 000 km on it and I have noticed what seems to be some weird behaviour the last couple of weeks. First off, all this behaviour is intermittent. It seems like it takes for ever to switch from first to second. I can be nailing the gas, I hear the revs go up but it just doesn't want to shift gears, and when it does, it sling shots you into second. And once the car does change gears, sometimes it seems like there is a lag depending house much gas I give it. Biggest problem is inclines. If the hill is more than 30% the car feels like a ten speed bike in tenth gear. No matter how much gas you give it, it wont change gear until you level out then the car picks up speed and finally changes gears. Also, a launch from a stand still produces a grinding feel from the seat of your pants. Haven't checked fluid yet, but there are no puddles in my usual parking spots that would indicate a leak. Any thoughts, am I screwed?

I would check the fluid and maybe even replace the modulator before blaming anything else.

Fluid color? Time for a fluid and filter change? (Not a flush)

Based on what you describe even that may be too late. Does the '96 have a vacuum modulator? If so, definitely look at that first. Check all your vacuum lines. ALL of them!

deekster_caddy wrote:

Fluid color? Time for a fluid and filter change? (Not a flush)

Based on what you describe even that may be too late. Does the '96 have a vacuum modulator? If so, definitely look at that first. Check all your vacuum lines. ALL of them!

Another thing I forgot to ask. When you get around to checking the fluid can you smell it? If it smells burnt then you need to change it. Like Deekster said though, it might be too late.

And yes, the 95-96 used a vacuum modulator. It's ~$20 at Autozone. Let me see if I can dig up a part number.

EDIT:

Mr.Riviera wrote:

after reading a few posts here and a few on the bonnie forum i went out and picked up a transmission shift modulator to increase the line pressure in the 96's 4t60-e tranny. p# MV303 at autozone. cost me all of $12 and took maybe 8 minutes to install.
the new one is adjustable by a small screw on the outside end.

Hey Guys, thanks for the responses. Well, fluid was actually low, it was at the add mark, but I just don't see evidence on the garage floor, and I checked it about two months ago? Also, color is red but in the darker range and yes, it does smell burnt, so it looks like a fluid and filter change is in order. Also thought about changing the modulator but just went to an AC Delco dealer here and it was $80, so I am gonna see if I can source out a cheaper one? It still worth doing all these things before going to a tranny shop. I just wanted to know if was too late for those things. How much damage do you guys think was done in the time the I last checked the fluid level to now?

Modulator:

http://www.autozone.com/autozone/parts/_/N-6o1zu?itemIdentifier=7502_0_0_

It's not the same as stock. This one is adjustable. Me and the other Matt (Mr.Riviera) are using them and they work just fine. As far as damage that would be Abaddons area of expertise.