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Originally Posted by firlandsfarm
My thanks to those who have expressed an interest in my problem and my apologies for the delay in responding to your questions. First let me give some more background.
The problem started about 3 years ago! My wife was 50 miles into a 300 mile round trip when without warning and for no reason the car refused pull away at a junction (could have been dangerous as it slowly crawled into the traffic lane). It gradually built speed and then ran OK for the rest of the trip. The problem then repeated itself after a long interval and continued to do so occassionally but more frequently until it became impossible to drive. It was referred to our nearest SVX dealer who diagnosed the need for a replacement gearbox (or strip and rebuild) at a price of c.£3,000 (US$5,500). I decided to dwell on this but after 2 years of "dwelling" with the car parked outside through 2 UK winters I feel the need to sort it. The engine started immediately yesterday with no more assistance than a jump from another battery so I diagnose there cannot be too much wrong with it! There is one other "happening" around the time the problem was developing and that is the pully at the top/centre of the engine came away from its spindle, it fell off! I cannot remember if this was before or after the problem first showed.
So, if I've not bored you to distraction, to answer your questions
Steve: yes revs=RPM (UK slang). My suspicion of the transmission is because I raised this problem a while ago on the UK group and was advised before spending money on the gearbox if the pre and post gearbox sensors are not working properly then the computer might diagnose false wheelspin and invoke the traction control preventing the engine from revving.
If I build the revs to 5,000 there is slight hesitancy up to about 3,000 (say 1 second) and then it flys (all the way to 7,000 if asked). The hesitancy is there with both fast and slow application of the throttle (unless that means I'm not applying it slow enough for your test!). The response does not change if in drive.
My wife never "mashes" the gas (if the UK translation of "mashing" is "giving it some wellie").
Last time I took the codes no mention was made of timing issues although it doesn't like the oxygen sensor readings. I doubt that timing is an issue as it starts so easily ever after a very long layoff with stale petrol.
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Engine or gearbox???????
The bit
My wife was 50 miles into a 300 mile round trip when without warning and for no reason the car refused pull away at a junction (could have been dangerous as it slowly crawled into the traffic lane). It gradually built speed and then ran OK for the rest of the trip
It depends on if the engine was reving hard, but the car not going. Or the engine was not reving, just staying at low rpms. The former would be the transmission, the latter would be the engine.
If it was the transmission, the forward clutch would have to be slipping, and the ATF would be dark and smell burnt. A torque converter problem would be the Stator one way sprag clutch. If it was slipping, it would accelerate slower from a standing start, and be ok at higher speed. But it would not be as slow as you say it was. If the Sprag was seized, it would accelerate fine from the start, but lack at higher speed. A stall test should show some signs of the problem.
This bit:
There is one other "happening" around the time the problem was developing and that is the pulley at the top/centre of the engine came away from its spindle, it fell off! I cannot remember if this was before or after the problem first showed.
If this pulley is the crank pulley, the timing belt sprocket behind it could have come loose also, may have sheared the key way, to allow the timing to move. This would link to the:
doesn't like the oxygen sensor readings
As far as the "traction control" goes. The Torque control only retards the ignition timing a few degrees, not enough to prevent it from accelerating away from a stop.
I tend to think it is the engine. If the key way has sheared the timing can move, retard one day, fine the next. Not to rule out a whole lot of other engine causes.
Harvey.
