How do you know when it's working right?

[peeeot]

Over the period of several months I've had my Cutlass, it's improved little by little. When I first bought it, the vacuum line to the vacuum tank was broken off and leaking, the ORIGINAL plugs had worn so severely that the gap was at like .06-something and the electrodes looked like new lipstick. It had the original plug wires and a catalytic converter that was broken up into chunks. All of this--and yet it ran well enough that my initial perception was that it was a healthy 85k mile car.

 

When I found that open vacuum line, the way the car ran in terms of noise, smoothness, power, etc all improved, of course. The new plugs didn't make for any obvious change. The wires smoothed things out even more. The Magnaflow replacement car eliminated obnoxious rattling and made for still smoother running. None of this is news.

 

All this to say: each time I fixed something, I figured the car was working properly. The car runs the best it ever has, probably markedly better than when I bought it-- but how do I know it's running as well as it should? There are little things that make me wonder. For example: immediately above 3k rpm, the tone and smoothness of the motor deteriorate noticeably. I read 18 inches of mercury at idle. There is a choppy sound in the exhaust that has diminished with each improvement but a hint of it is still there. It still feels lethargic under acceleration, especially merging onto highway traffic.

 

I just want to know if this is as good as it gets or if I need to keep looking for little problems, like sensors slightly out of range or weak coils or who knows what.

[rockfangd]

well i really think you are in the same boat as me as my 94 cutty nicke and dimes me , besides the mods

[jeremy]

how do I know it's running as well as it should? ...For example: immediately above 3k rpm, the tone and smoothness of the motor deteriorate noticeably. I read 18 inches of mercury at idle. There is a choppy sound in the exhaust that has diminished with each improvement but a hint of it is still there. It still feels lethargic under acceleration, especially merging onto highway traffic.

 

 

those symptoms would tell me that there is still something wrong.....the car shouldn't get rough at 3k rpms and shouldn't feel lethargic....although the 3.1 isn't a speed demon either. Have you ever driven a 3.1 w-body in good shape to compare the two?

[peeeot]

nope, I've never driven an equivalent 3.1. I'm inclined to chalk the lethargic-ness up to the 3600 pound curb weight of the convertible, but I thought the same thing when I first got it and it was even slower.

 

I could take the coils off and test them with a multimeter; that may be worth my while. But what else can I do, short of replacing random sensors or having some professional with computer diagnostics check it out? I don't want to do any of that unless I have reason to believe it will make a difference. I mean, it's not like I have a service engine light or anything.