abnormal 1st to 2nd gear change. 2.0 petrol autobox

[knpenny]

Hi guys, just in the last couple of days, my gearbox seems to have changed slightly, between first and second gear.
Symptoms: 1 Sometimes i get a judder when pulling away from standstill or when i've stopped at lights and pulled away again.
2 A couple of times when i am moving in slow traffic and go to speed up it trys to rev high (i dont let it) so i release the throttle and accelerate away without issue(never happens twice in the same go)
3 Sometimes when its changing between 1st and 2nd, it takes a second or 2, then changes with a jolt ( like its jumping into the 2nd gear.

These symptoms are a bit random but the judder happens more frequently on hils, up and down.
Could this be a selector issue between 1st and 2nd and if so what is most likely to be the fault.
Again it doesnt happen all the time, less often than not.

Oil level is spot on and its new with the filter cleaned when i did the oil. Tends to happen more when the gearbox is cold.

If someone knows of simmilar or same symptoms i would greatly appreciate any input
Thanks in advance. Kev

[Bonneville]

Did this occur after the gearbox oil change or before?

[WebWiz]

Did this occur after the gearbox oil change or before?

Good point. And what was the state of the old oil like? Did it smell like burnt toast?

Sometimes when you change the oil, if it was previously really bad, the new oil cleans out sediment and swarf that was actually helping to mask a problem by blocking holes or binding worn friction parts. once this residual junk is gone it means you get less friction, open holes etc and possibly blocked valves.

Is the HOLD light flashing?

[Bonneville]

I agree. I've done most things with cars and bikes but I won't touch an auto box. Specialist gear and knowledge required. Even on an oil change, they use a dialysis machine to chase the old oil out and pump in the new. I use a chap up the road from me who charges about £120 for the service unless it's a Benz 722.6 which cost me more for some reason (special oil, I think).

[knpenny]

after the oil change and no hold light flashing, all other gear changes are sound.
I did the full purge with sump removal and filter clean, as i remember the oil smelled normal, just a bit dirty and there was quite a bit of sludge/sediment and the sump magnet had some swarf on it.

[Loopyboots]

Am having auto gearbox woes also; My 2.0 Aero has been in and out, mostly in, garages this year with a similar set of symptoms. My local specialist auto gearbox garage have rebuilt the gearbox, replaced the torque converter, (at massive expense) were sceptical when I reported no improvement, and now want to put a new 'valve body' on it. (Looking this up it seems one of the symptoms is shudder - so perhaps that's worth a look for you?)

I will say I'm no mechanic (beginning to think Bongo owners need a qualification to keep them going) but hope this is useful.

[knpenny]

let me know how you get on, it sounds worrying if its the valve body, it controls hydraulic fluid flow for proper and smooth gear selection. As far as i am aware if it was that, it would causz a judder on more than one gear,
I can report that the judder is becoming less frequent the more the days go on, but the selection between 1st and 2nd still seems to be the same, depending on the revs applied it can still change smoothly.

[knpenny]

Still haven't solved the issue yet but it doesnt seem to be getting any worse
I was hoping Alacrity may be able to shed some light on this, I have found that the problem occurs more often when pressing the brake at low speeds and if i dont wait a second or two to accelerate, mostly on hills (up or down), and accelerate. Its a weird one.

If anyone has any idea or experience, it would be greatly appreciated, as i dont have a bongo specialist over here.
Also does anyone know a bongo specialist that knows the autobox well in the south east of england?
Thanks ,Kev

[Merlot man]

Sorry to hear your woes ,
I've had gearbox problems last year on my TD bus but hold light came up , similar to yours and it was the valve solenoids
I got great advice from acactiy the last time , also on advice I talked to this crew
http://www.dunnings-automatics.co.uk/home/3698978 As I needed a lock up valve and they had one second hand ( rare to give trouble apparently )
What was most impressive about them is that they had a chap who they considered their "bongo man " he gave my mechanic and I great advice over the phone as , like you , I'm not living in England but Ireland ( going to France with it next week or two )
They would be worth a phone call in my opinion .
I wonder even though the hold light isn't flashing would it be worthwhile reading any codes that might be on it ?
Can't do any harm ?
The codes are on here some place and they are easy to read , even I can do it !
Don't worry I'm sure this will work out well
Brian

[Bonneville]

I'm trying to find out more about the box itself. Mine has UM100 on the tag but I suspect it has another manufacturer code as well as the Mazda designation like JR405E or something.
Is yours also a UM100?

[Alacrity]

Difficult one to diagnose over the ether, judder on pull away (assuming it is the gearbox not prop/driveshaft) is normally the forward clutch starting to slip, which can get worse as 2nd engages. When you say it revs up, is it driving or slipping?

We are based in the South East, at Hailsham, just north of Eastbourne.

[knpenny]

It slips when it revs up but its at random, it seems to do these things mostly on incline/decline.
Like you pointed out the judder is only occuring between 1st and 2nd. Actually now you mention it the judder occurs twice when its engaging 1st and like you say when going into 2nd its a bit more noticable

I have noticed that it takes a second and a half to engage the first gear from neutral or after pressing the brake/clutch pedal and thats when it mostly occurs. Thanks for getting back, I'll be honest that i've kinda been waiting for a response from you cos i know you've got bags of experience with auto boxes.

If it persists and gets any worse i think I'll change the clutch and if it stays the same till next year I'll pop in to your gaff for a proper diagnosis.
Much appreciated

[knpenny]

Thanks for the response brian, I'll give em a bell. I did at first think it was a selection issue, but I'll get more info before deciding what to do
If your doing a big tour round france and like landscape stuff then you should definitely visit Les Voges, franche-comte and jura. Lovely country France and its been a good atmosphere recently after they won the world cup

[Bonneville]

I think this is the 2.0 gearbox so you can watch someone change a forward clutch

https://www.youtube.com/watch?v=Vd8KAgSW74k

I'd get it to Alacrity while it still moves.

[knpenny]

Dont suppose you know where i can fid a clutch kit, the bongo is a 2000 2.0 petrol. I'm finding plenty o diesel ones but having trouble finding the petrol ones. Thanks in advance. kev