

Joined the site some time ago but this is the first time that I've posted. Would be very pleased to receive some advice, or a steer, on a problem that I've been having with 'Woody', my Bongo.
First, a bit of background info; I'm situated in North Somerset and own a 1997 2.5TD which, although having covered 286k kms, is in really good condition. At the end of last summer, I had Clearcut Coversions of Barnstaple fit one of their 'Weekender' rear kitchen conversions, and it's now a brilliant vehicle for my wife and I to just head off whenever we choose. The year before last, we toured Spain, Andorra (that didn't take too long!), and Portugal, with Woody covering well over 4000 kms without so much as a missed heartbeat. Additionally, it used not one drop of oil or coolant...faultless! However, I did notice one 'issue' that I'd like some advice on.
The automatic gearbox doesn't always seem to know which gear it should be in, if that makes any sense. It's not during initial accleration, but more so at greater speeds. So, starting from cold, it changes gear OK, sequentially, up through the box without any particular clunkiness, and finally moves into top gear. However, if, say, I was then cruising along at 60mph in top gear and driving circumstances in front of me required me to back off of the throttle, with a resultant loss of, say, 15mph, reapplying the throttle would cause the gearbox to appear to be uncertain about which gear it should get back into. So, it would probably select too low a gear and then momentarily 'sort itself out' by subsequently engaging a higher, more appropriate gear. Although climbing the Pyrenees appeared to present no problem to 'Woody', upon my return I asked my local garage mechanic to check the gearbox out with a test drive. He came back to me and reported that he could find no issue or fault with the box at all. He also checked the oil and said that it was a perfect cherry red with absolutely no signs of degradation or overheating.
Looking through the experiences of other Bongo owners and their gearboxes, I can't find any reference to any report of the exact same issue as mine, although I do see that the Throttle Position Sensor and the Gearbox Solenoids seem to figure in some gearchange problems.(Perhaps I ought to mention at this point that the 'Hold' light has only ever flashed the once of its own accord in the 3 years that I've had the vehicle). Of course, both of these components are expensive, so I'm not really in a position whereby I can easily buy and try new ones of each to see if this cures the problem. I did take the vehicle to a local auto-electrician to see if he could diagnose any fault codes, but he said that the van was too old to gather sufficient information. So, I feel a bit stuck in trying to resolve this matter.
Can anyone please point me in the direction of a reputable or reliable specialist in North Somerset who could provide me with a reliable diagnosis of the fault, or does anybody have any other suggestions as to what my next course of action might be? We're looking to repeat the Iberian road trip again this Autumn (the ferry's already booked!) but I'd feel a lot happier knowing that any potential gearbox problem had been eliminated.
Keep up the good work, guys, and thanks in advance for any help or advice that you might have for me.