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sharkey
29-03-2008, 05:47 PM
Some of you may recall that my car was in the garage due to a loss of power from the gearbox. Turned out some of you were correct in your assumptions. It was indeed a blocked filter. In addition, the torque converter needed changing.

The car has returned and apart from being £1031.00 worse-off, I'm not a happy bunney. It no longer feels like my car. I've just received it back a second time having reported that it occasionally 'slips' gear momentary (particularly when cold). Plus, in the lower gear exchange there is a shudder which transfers through to the front wheels. This occurs when I press on the 'gas' firm but not excessive (around the 3000rpm area). Typically, both problems are intermittent

The local tranmission place I took it to reckon that re the shudder, the "gear plates/clutches were left on a bench, therefore gear oil dry spots had occured. They reckon this will diminish as the new oil mixes" (I'm not convinced).

One major difference is the gear changes. It seems to rev for a longer/higher period before it changes up. And when it does, it returns with a extremely recognisible thud.

The work is guaranteed so I can return the car. I just need and would really appraciate any assistance before I return it for a third time.

Steve.

AR
29-03-2008, 06:35 PM
Mate if the work is guaranteed and you are not happy, return it until is right.

Cheers,

AR

Silver Surfer
29-03-2008, 08:58 PM
Calling Britlude.......!

SS

britlude
30-03-2008, 11:21 AM
why me??? lol

glad we've got half way there with the blocked filter, shame it's cost £1030 tho! i'm guessing most of that was the converter, as they can't be rinsed out and cleaned like the rest of the gearbox, to do that they have to be cut apart and then re-welded, hence cheaper to replace!

the joys of intermittent faults is they never happen when they're at the garage! but will just as soon as you are on your way home! the shudder may well be plates/clutches re-oiling/realigning, i have no idea, it may be that they are settling in place again, but the slipping is usually either a lack of hydraulic pressure on the gearbox bands, the bands themselves out of adjustment or the gearbox getting the wrong signals from somewhere. tho if it's been rebuilt properly
the first 2 shouldn't be an issue...

On my hotrod if the kickdown linkage gets moved (as it did in the winter tweaks!) i get the box slipping at various times or holding gear for too long/hard shifts. now i'm fine tuning the kickdown linkage to try to get the box behaving the way it did before i changed the kickdown on the carbs!

the symptoms i'm seeing with the rod seem to be close to yours (spooky huh!) now I KNOW mine is down to the kickdown/throttle position linkage to the box. there must be a similar system for the NSX box to know where the throttle is be it a physical link or electrikery... there's alot of electronics involved with the NSX gearbox, it might be as simple as unplugging the wiring to the gearbox, spraying in a bit of WD40,and plugging them back in!

at one point my gearbox was doing strange things after i disturbed the connector to the gearbox ECU (while fault finding the TPS ECU, again dirty connector/joins) and that resulted in late changes/ revs flaring at changes, and so on... ok, i know on your car the ECU is unlikely to have been touched, but the other end of the wires most definately have!

that'll do for now!