94 Lesabre Engine/Trans problem???

I have a 94 Lesabre with 103,000 miles. Lately while driving on the freeway at 60-75 mph/ 2000 rpm, if I step on the gas lightly it feels like the trans has a slight hiccup to it and then goes fine. When I am climbing a hill and stepping on the gas it does a bunch of hiccups in a row while the rpms continue to rise. I watch the tach and it seems that it moves about 100-200rpm when the hiccup occurs. I have heard that if a trans is slipping it will rev 500-1500 rpms while slipping. About 18 months ago, I experienced a slight hiccup and we traced it to a bad spark plug wire. I replaced them all and things have been fine until recently. Can spark plug wires go bad so soon? Any ideas or test that I can perform. I had the car in the shop on Monday and the guy checked the transfluid and he said it was fine and didnt recommend a fluid change at this time.

Kinda Frustrated

Jack

Sounds like an ignition misfire, how old ar the plugs, make sure all the wires are on properly.

Hey everything is possible. both expensive and cheap plugs and wires can go bad prematurly. good luck

Plugs are about 20 months old +/- 22,000 miles. I will check plugs and wires this weekend. Does it sound like a possible trans problem? If the plugs and wires check out OK?

Thanks

Jack

Just curious how a misfire could cause the RPMs to go up. My intuition tells me that a misfire would cause the RPMs to go down if anything since not all cylinders are contributing to produce power as they should be.What am I missing here?

Now I can see how a slipping transmission could cause high RPMs since when the transmission slips the load on the engine is lighter allowing the engine to increase its RPMs. I've experienced that myself.

A misfire would not drop the rpms then as it comes and goes restore them back up? Based on the hiccup" description" that sounds like a misfire, but yes a slipping tcc could also display these symptoms, but ign first or scan it with a trans capable scanner and look for slippage errors. Normaly the tach does not respond instantly to rpm changes so it can be hard to connect the movement to the engine/trans conditon, driving this car for us would reveal what this actually is, but here we sit.

My 94 Park Avenue once had the same symptoms. It turned out to be the EGR valve.

Mine didn't close properly anymore, it was always open a little bit. So it was recirculating exhaust gases even when it wasn't supposed to, resulting in misfires.

I seem to be having a similar problem. At about 47 MPH under a load (going uphill) the car surges. Ocasionally it will stall especially when coming to a stop. I was thinking I had two different problems but I am now thinking it could be a faulty torqe converter lockup solenoid. at speed, it could be chattering and when coming to a stop, it could be locked up and killing the engine.

Ok, first off, if the first problem seemed to be the tranny hickuping, it could just need a good tranny flush. I've had probs like that before where the screen filter gets plugged up.

Now, about the stalling out at stops and what not. That sounds like an EGR valve problem for sure. I had the same problem and it was driving me crazy on my 94 leSabre. I bought a new EGR valve from Rockauto.com and put it in myself in about 15 minutes as it sits right on top of the engine.

Check that out and see if that will solve it.
Best of luck,
J

Fm PA DriverMine didn't close properly anymore, it was always open a little bit. So it was recirculating exhaust gases even when it wasn't supposed to, resulting in misfires. As you noted, the EGR valve is supposed to be closed during idle, or below (((>est. <))) 1,500 rpms. However, if the EGR valve is stuck open, the issue would exist whenever the engine was slowing, to below 1,500 RPMs -- always. With the resulting sensation of the engine going to stall, when slowing down for a stop, or driving slowly....