2000 Lesabre Transmission shutter

[Ralph50]

My car seems to have a shutter at the 1st to 2nd shift. Its very slight and some probably would not notice. I still have one month left to my warranty. I took it to a chev dealer. They said the transmission pressure was high. 1500 dollars. I said no way, that was not even a rebuild just to fix. Anyone heard of this?

[Jrs3800]

Sounds like you have an issue with the Pressure Control Solenoid... If you are getting a clunky or harsh shift, the high line pressure can harm the trans...

$1500? Is this not covered under warranty?

[BNaylor]

Originally Posted by Jrs3800

Sounds like you have an issue with the Pressure Control Solenoid... If you are getting a clunky or harsh shift, the high line pressure can harm the trans...

Plus it would not hurt to get it scanned with a trans capable scanner/scan tool and see if a P1811 DTC (max adapt, long shift) is set. When that DTC sets it commands maximum line pressure and disables shift adapts which will then cause the erratic shifts, shudder or hard upshifts.

[Ralph50]

Well I took the car to the Buick dealer I purchased. They said they replaced the PCS. It shifted pretty good for a week but it seems every once in a while the shutter comes back when shifting. I really dont know if they took it apart or not cause they were supposed to charge me the deductable but did not. Also just had a engine misfire fault code and another mechanic replaced the spark plugs and wires, $200 and said there were no other codes stored in the comp. I guess I will live with the car and its little idosynrocies.

[HotZ28]

Another common problem of "shudder" can be caused by the EGR. Remove the EGR and use a small screwdriver to push the pintle down shown below. It should move freely and spring back into position. You can observe EGR position with a scanner and watch the position range from 0 @ idle to near 100% @ full throttle. If the pintle is sticking, this can cause misfire, ignition retard and the "shudder" or the chugging effect.

[Ralph50]

Very interesting. Maybe a connection to my fast idle when cold! Cold RPM is about 1400, seems too high. Comes down when warm to about 700-800 idle in gear. Other posts suggested the idle control pintle, clean.
Do you think I can remove the EGR without damaging the gasket, I once cleaned one on my 96 Transport and had a hard time fining the gasket without buying the EGR.
Thanks for your help..I wish to you a great week.

[HotZ28]

Both the IAC & EGR pintle are subject to malfunction due to carbon deposits. The both should be removed & cleaned. After cleaning with carb cleaner, be sure to lube well with PB-Blaster. You should be able to get an EGR gasket at any national parts chain, they look like the one shown below.

[BNaylor]

You need to check with the dealer and see if they cleared the TAPs (transmission adaptive pressure) info stored in the PCM module. That way it can properly relearn your driving habits and re-establish shift points and how it will shift.

If the shudder is very minor I would not worry about it or fix what is not broken. Also, just for reference how many miles do you have?