QuestionQUESTION: Hi,two questions for you, first the auto is playing up in overdrive.Cruising (in what i assume is overdrive) with less than 1/4 throttle doing (for instance) 2400rpm, when any more than 1/4 throttle is applied- transmission will change in to a higher gear (top gear?) and rpm will drop around 400-500rpm making it struggle up inclines ect. The change between these gears/speeds is not tight- as if a slipping clutch in a manual, there is no slipping once the change is complete. then when the throttle is backed off to a certain piont(1/4) it will kick the engine up 500rpm. The trans is about ready for a fluid and filter change but so far has not been done.
Second, whilst accelerating before the turbo kicks in the engine misses and stammers a little bit, then has good power when turbo starts working. i think ive also noticed a knocking sound while its missing and so forth. Fuel consumption is a bit high for what id expect, although the vehicle is new to me and so i know no different for this particular vehicle. These two problems combined may result in the excess fuel consumption.
Cheers for any help, Simon
ANSWER: Simon,
First there is a kickdown linkage that sounds like it needs adjusting. To do this, engine off, have someone press the gas pedal to the floor and hold it. Under the hood note the tension on the kickdown linkage and loosen the lock nuts until you can adjust the cable taunt. Not overly tight. But, with little slack. Currently, it is probably really loose and this causes the upshift before the proper time.
The stumble, miss, before the turbo kicks on is probably due to the need of a fuel filter replacment, some injector cleaner and the like. If it is running lean it will starve for fuel prior to the turbo spooling up. Also, check the turbo to make sure it is turning freely and not binding. This old and it has to have been replaced or rebuilt.
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QUESTION: Hi Von, i cannot find a kickdown linkage on the accelerator assembly. There is something like a throttle position sensor attached to the top of the injector pump on the accelerator mechanism but no extra cables except the idle up cable. the 'throttle position sensor' looks as though it can be adjusted...
Simon
AnswerSimon,
I would assume either the throttle position sensor is either out of adjustment or the transmission computer needs to be reflashed. That is, the shift points can be adjusted through the computer if someone has a Consult II scantool or the like. The scantool is from Nissan and it costs about $100 dollars US to get a reflash. Check the position sensor and if that checks good then check around for a transmission shop that has a scanner to adjust your shift points. They can be adjusted with a shift kit if a scantool is not available.
