How smooth idleing is an '86 951?

[coupe]

I was sitting in my car with a Porsche workshop service manager a couple of days ago, and I pointed out that my cars still shakes and shuders while idleing even after all the repairs that I have done, including new engine mounts.

So he said that even if a bought a brand new engine, the car would still vibrate in idle and feel rough.

I really just stopped listening to this guy at this point. I thought that this guy doesnt know what he is talking about.

So my question to you all with better cars, How smooth are these cars, especially a 951 made in 1986????

Thanks.

[Blackfoot]

well, i have an '86 which britwrench says the motor mounts will soon go bad, yet it idles smoothly. so i think your problem isn't the mounts, unless they were installed incorrectly, which seems unlikely.

fiat pics?

[Lawrence Coppari]

Mine is smooth when it is warmed up if and only if the AC is off. But what is smooth? It is not as smooth as my 400E V-8. It does not stumble or shudder. It is fairly smooth. Has your flywheel been lightened by any chance? Hard to quantify.

[Scott R]

Mine is very smoothe in comparison to other cars, even newer cars. In fact I can't even usually fell the engine running.

But this was not always the case, I had vacuum leaks and a torn J-boot that caused the thing to shudder at idle. I would bet that if you have good compression then there may be another issue.

[coupe]

Well, the way I see it is that it is way to rough for a Porsche. As far as I know the car is full stock, with the exception of a free flow exhaust system and the removal of the catalitic converter.

[coupe]

This car is a 2000 cc 5 cylinder, 20 valve Turbo charged developing 220 BHP. Year model 1997

0-100km/h in 6.5 s
Top speed 250 km/h

This cars engine is really smooth even with 5 cylinders

[Lawrence Coppari]

I can feel mine running but it is smooth.

Didn't see any trees in the background of your Fiat pix. ;-)

[1.2gees]

It should be fairly smooth. To compare, I put a glass of water on the intake manifold @ idle, and the water did not seem much different vs. a 98 honda v6 in top shape.
Ahmet

[Roger Hall]

Does the 951 have balance shafts?

[Scott R]

Yes

[Frank B]

of course.. sounds like the belt is not aligned

[coupe]

I'm getting the timing belts looked at again this coming saturday, as some of you may know, my new mechanic got them fitted wrong.

I have also ordered a new distributor cap and rotor, and new 8mm ignition wires.

I hope all this will smooth it all out.

I also have to look closer at the after market exhaust system fitted, and may have to renew most of it. I think that one of the problems may be here.