Drivetain slack and lurch.... - David Stone
I've previously posted a message about this, but I think my might have narrowed down the issues now.

I have a Mazda Xedos 6 2.0 V6 1996 60,000 miles Manual. The car has been test by Mazda who say that there's no fault. The car's engine has also been checked by a tuning company who have made a few tweaks here or there. The oil, air filter, ignition leads and throttle switch have been replaced but.....

.....everytime I'm in 1st or 2nd gear (it's occurs mostly in 2nd) and I accelerate quickly with half throttle of more, there seems a delay before the transmission "bites" and the car accelerates. Because of this delay, the car lurches forward. The car doesn't seem to be able to accelerate smoothly unless I gradually apply or I'm really gentle with the throttle. When I'm decelerating (again mostly in second) between 40mph and 20mph again there's a slightly lurching / kangaroo hopping even with my foot off the accelerator. The car doesn't seem to be able to decelerate smoothly.

The techies (Mazda and the independant car tuning company) say there's no fault with the engine. The independant car tuning company have noted that there's seems to be a bit of slack in the transmission.

Mazda have suggested:-

1. The V6 Mazdas "are a bit like that."
2. It could be a gearbox problem.
3. I'm imaging it.
4. My feet are too big.

Any ideas / solutions / suggestions would be greatly appreciated, otherwise it's going to make its next appearance in the Classifieds section of Autotrader.
Re: Drivetain slack and lurch.... - Andrew Bairsto
Providing 1 to 4 are nopt the reasons could it be a clutch problem,

a sticking release bearing or pressure plate will be much more pronounced in the lower gears.
Re: Drivetain slack and lurch.... - Andrew Barnes
I had these symtoms when the driveshafts on my old Golf wore out, it was the CV joints I think. The car jolted when lifting off the accelerator and again when accelerating.
HTH
Andrew
Re: Drivetain slack and lurch.... - Tom Stoddart-Scott
Don't know whether it is any use but a mate has just replaced the rear suspension bushes on his BMW 320i which were knackered were causing excessive vibration and also incredibly bad jolts when accelerating and lifting off in the lower gears Is the Mazda rear wheel drive can't remember

Good Luck

Tom

p.s. the clutch idea is also equally worth considering
Re: Drivetain slack or ECU? - D J Woollard
Come on Andrew/Adam (Tune-Up Ltd), this must be an ECU or engine management issue.
David
Re: Drivetain slack or ECU? - Andrew Moorey (Tune-Up Ltd)
We had a look at this car last Saturday in Brighton. What we found was that the throttle body and base idle speed screw were heavily contaminated with oil sludge from the breather. The HT leads had signs of early tracking inside the plug boot. The throttle contamination was cleaned out and the base idle was reset as per manufacturers instruction and the throttle position switch reset. The switch itself was not in good order so a replacement was recommended along with leads, cap and rotor arm. The air filter was absolutely filthy so as a new one was not readily available was shaken and brushed out. Having done all this everything else was checked and no faults found. After this the car was test driven and pronounced much smoother but the lurch and jerk was still in evidence as when the customer (David) floored the throttle from about 1500 rpm there was a noticeable jerk, not hesitation, from the drivetrain. In conclusion we feel that this is probably the problem area. The only slight query is whether the replacement throttle position sensor has been correctly set up, bearing in mind that the contamination of the throttle body, the fouled air filter and out-of-adjustment sensor had not been picked up previously.
Regards
Andrew
Re: Drivetain slack or ECU? - David Stone
Thanks for providing the technical explanation!
Re: Drivetain slack and lurch.... - Ian Cook
Have you thoroughly checked the engine/transmission mounting rubbers. Any slackness here can cause havoc with drive train take up. You may need to carefull put a jack under parts of the lump and gently lift it, whilst observing how much give/compliance etc there is.

I know that many transverse installations have a stabiliser bar/shock absorber/mount arrangement (seem to recall it on Peugeot 405) to prevent excessive fore and aft engine movement.

Worth a check?

Ian
Re: Drivetain slack and lurch.... - David Stone
Okay, I'm taking all your suggestions to the Mazda garage on Saturday to see what say.

Any more ideas / or suggestions would be welcome (extra ammo to throw at them!)