1st, drop to 1st gear on shifter, any change?

2nd, leave in first gear and step on it, the rev it and see if it screaming at 40 mph or can go all the way up to 70 mph. You won't be able to do 70 mph in 1st. But easily in 2nd.

Note carefully the shifting during normal driving too, mine is somewhat harsh (firm, hard, a shift that means business) in shifts (V4P car), I don't know if all FWB/Impalas/RMs are.

Manually shifting it and starting in 1st is a great idea to check that!

But, manually shifting should not raise shift pressures (if I'm understanding you correctly) and it should shift as hard/soft as you would feel normally.

But, again, but if you see a real difference manually shifting it through the gears and you see that it IS starting out in 2nd when you select D, then what is causing that????

Brian 96 Impala SS / 96 FWB

It does start in first i checked it today and besides feeling the same when i manually have it in 1st i also feel the 1-2 shift which is a little harder than it used to be.


nowadays if i ride the gas through the 1-2 shift it shifts harsh this started last summer when i was drag racing on an in ramp to the expressway not too harsh but more noticeable than when new

You don't have a stuck PCV valve or something do you? It would make it doggy until you get going. The ECM would be showing a way off long term fuel correction, and once long term gets set, short term should get back around 128. But it will be fluxating much more wildly than with no vacuum leak.

Sounds like something got put together wrong, connected wrong, or is leaking.

Fuel pressure regulator do anything like this? (I can't imagine it would, but...)

I haven't read up on the flow charts on the 4L60E, but on the THM350/400 manual shift does increase fluid pressures across the board. The flow circuits change a but.

I'm still waiting until i get the exhaust bolt back on right now i have the car torn apart with the exhaust bolts removed I just needed to order a right angle drill so im waiting for it because sears has them for 99.00 and I don't want to spend so much for a drill that will get hardly used.

I'm also upgrading to grade 8 OEM exhaust bolts I bought from ebay so that I won't have this problem again. I should be done by friday or sooner.

As soon as im able to get this bolt removed i'll put it back together and see if this fixes my problem or else ill invest in a the akm cable so that i can plug my laptop into the car and see the details of my cars pcm etc.

The only other strange thing is lately i get a strong fuel smell just from backing into the garage which takes maybe 10 seconds at most and then the garage smells horrible for a couple minutes which didn't happen before could the exhaust leak cause this?

by either leaking exhaust or by causing an incorrect adjustment by the o2 sensor causing too much fuel too be burned?

the way my car behaves well most of the time is when i step about 1/4 of the gas down its ok but anything harder it won't react like it used too or is supposed too it just acts like if i am only steppng about 1/4 down on the pedal.

I wonder if the knock sensor is \"seeing\" the noise from the leak and pulling back timing. Else I can't se how an exhaust leak could ever hurt performance. The Opti treats the LT1 as 8 1cyl engines, so if it sees the leak as a knock on one cyl, it will pull that one cyl back for sure.

If....

I guess you can pull the 2 knock sensors and drive and see how it does. If power returns, that is the problem. Or can you simply remove the knock sensor module in the ECM?