Strange problem car didn't change down
Hi,
I went for a drive last night got out of my drive pulled up at junction and the car was juddering badly as if it was about to stall! I thought it maybe cold or sumthibg went to accelerate and hardly any pickup and then went as usual again... Then decided to pull up did the same thing again so I changed down to 3rd it did the same thing changed down to second and it stopped and moved back into 4 and didn't do it again until I drove home.
I pulled up and there was a slight leak under the car near gearbox.
What could this problem be ??
Many thanks
joe
do you know what was in the leak? Water, fuel, oil, transmission fluid?
Hi it could be lack of vacuum supply to the gearbox modulator valve ( located to the rear on the offside of the gearbox) with a thin plastic pipe connected to it---no vacuum ---- erratic gear change..........
hey,
Yeh I had the valves checked out a while back when (I think) you mentioned about them in another post of mine... The mechanic said they are fine and nothing wrong with them :/
Hi It is the vacuum supply you need to check.... there are many thin plastic pipes around the engine that distribute vacuum... any one could fail and as a result "no vacuum" for the modulator valve..the cold start requires vacuum ..the EGR valve requires vacuum . the auto advance on the distrbutor requires vacuum all have different pipe runs and any can leak...as I said no vacuum ---erratic gear change --amongst other things......
hmmm fair enough :]
Where can I find it? Is it a job i can do? Also I looked before and could only find the diff lock pipes and they were leaking so fixed them but couldn't find anything :(
Obviously it could caked in mud etc lol
Many thanks
Joe
Hi you are looking for very thin 2mm diameter grey or black plastic/nylon pipes.. an obvious one runs from the base of the distributor around the front of the engine to the EGR valve on the top of the exhaust manifold..the others will look the same.any one with a hole/crack or disconnected will dump the vacuum and may well affect the braking assistance from the servo as well.....
AhhhhhH! Is there a vacuum pip going into engine next to the temp gauge cable? If so I knocked these of when I replaced my rad and but them back on but wasn't sure where this little pipe went! and stuck it on the one next to the temp gauge cable...Wonder if this could be it???? I remember it being a bit brittle !
Hmmm i wonder!!!!
Hey!
I've decided I'm gonner just buy some vacuum pipe and have ago at replacing them myself! How easy are the ones under the car to replace? Also what size pipe should i go for 2mm or 3mm?
Many thanks
Joe
Hi get the same size as you remove ..you will also need some oil resistant rubber pipe because most of the joints are rubber pipe ...make sure the bore size is such that no leaks are possible ..**** note there are some connections under the inlet manifold that are not easy to get at such as the cold start system plumbing.....
Hey!
Well i did some looking under the car and found an area covered in oil although it didn't look like it was coming from anywhere there. So I moved up the car (towards the front) where there is a sort of square pan type thing that was ok I then moved a bit further forward and found there is 2 like unscrewable plugs (aleen key type) about just under an inch circle. One is pointing directly on the floor and the other is more eleveated and facing towards the back. I noticed that the one facing the floor had no bolt in it. I went to my old g wagen and that had a bolt in it but the allen key part of it has had it.
So does this bolt drain the gearbox of fluid? and where can I get a new or second hand one from?
Many thanks
Joe
Hi the square pan type thing" is probably the oil pan for the automatic gearbox ..if you moved further forward there is a "fording plug" which fits into the bottom of the bell housing in front of the gearbox oil pan..it is only to be plugged if you intend to go into deep water...however... if there is oil coming out of this hole then either the front seal in the gearbox is leaking or the rear crankshaft seal of the engine..I cannot identify the other plug you refer to......
Hey!
I had a look around the manuals on this site and its calledthe "Torque convertor drain plug" If thats any help?
Many thanks
Joe
I am assuming from the previous posts that it as an auto box, you do not actually say so. I am sure the problem is as follows. on the LH side of the gearbox, looking forward. there is a is a small flat control box in behind the selector lever, it is the start and neutral isolation unit is connected to the ignition electricaly and has a series of segments/contacts in it, These units break up internaly and short out causing all kinds of seemingly unrelated problems with gear selction starting etc, change the unit and I think you will have solved your problems.
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Hey I wudn't no the difference between oil and transmission so id say its one of those 2!
Also I forgot to mention just before it happened it made a noise inside the car that kind of sounded like a phone on vibrate as it changed up through the gears a kind of "zzzzzzzzz" noise and its only been doing this lately but not as bad. But this problem could be linked to my other problem in the electrics forum as the fuse linked to the automatic kickdown etc keeps blowing!
Cheers
Joe