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        General >> Problems >> Violent gear change
        
(Message started by: GeraldineGreene on Jun 26^th, 2006, 9:56pm)

Title: Violent gear change
Post by GeraldineGreene on Jun 26^th, 2006, 9:56pm

Hello to everyone out there, my name is Geraldine Greene and I am a '96 24v Cossie in some Ford dark green colour!?
I have just acquired a new owner and they seem a little stumped by my violent gear changes. My fault occurs going both up and down the box although on the very odd occasion I drive smoothly. My gearbox oil is as clean as a whistle and my MAF is too. There is no unusual delay in selecting a gear.
Please could some wonderful knowledgeable being out there help my new clueless owner!
Many thanks.

Title: Re: Violent gear change
Post by derekne on Jun 26^th, 2006, 10:17pm

Whats your wireing loom like?
Im getting awfull problems with my clutch.
I think I need another new one. My drive is very very steep and I used to have a boat on it. Which needed shunting of and on and that has frankly taken its toll.
I am finding a crunching noise when engageing. Sometimes I cant get reverse. As soon as I dip the clutch I get a grinding (knocking noise)
With other cars its been the thrust bearing wineing on (squeeling)
Its getting worse and worse with every journy it will be no more than a month. With a hefty clutch bill of a few houndred pound. Will be unavoidable. Sometimes just to get it to go I have to switch the engine off to get ti to engage my manual 1st gear.
Regards.
Derek

Title: Re: Violent gear change
Post by GeraldineGreene on Jun 26^th, 2006, 10:23pm

Hi Derek
Haven't got to the wiring loom yet although this has crossed my mind.
Will have to check it out tomorrow night.
I have only had the car for 2 days and other than this she is a dream to drive.
Fingers crossed for yours.
Many thanks.
Ania

Title: Re: Violent gear change
Post by taliban on Jun 26^th, 2006, 10:34pm

might be a case of getting used to the car, the cossie is a powerful engine kicking out quite a few horses and as such is likely be a much more sensitive throttle just wanting to surge forward at the slightest touch ;D

Title: Re: Violent gear change
Post by GeraldineGreene on Jun 26^th, 2006, 10:40pm

It doesn't seem to be the power that is the problem as this occurs even on deceleration. It is very bizarre as I am not entirely sure that she is reaching fourth gear. There are no unusual noises or any other obvious symptoms.

Title: Re: Violent gear change
Post by fordcos on Jun 27^th, 2006, 8:27am

it sounds like the usual cossie problem wiring loom needs repairing

Title: Re: Violent gear change
Post by mazzy_j on Jun 27^th, 2006, 8:44am

Is your speedo working correctly? When the VSS sensor on my cossie has failed the speedo and associated trip computer didn't work, and the gear changes were quite violent. New sensor fixed the problem.

Matt

Title: Re: Violent gear change
Post by davem on Jun 27^th, 2006, 12:20pm

I presume this in an auto :-) I once had violent gear changes (auto box) and I finnaly found the fault to be a bad connection on the Wide Open Throttle switch (under the plastic Cossy housing)...and basically the gearbox (and/or PCM) didn't actually know the throttle position, so gear changes were jerky and/or at the wrong time. So, it's not always the wiring loom (discussed elsewhere) and the rubber insulation inide the WOT switch often warps and prevents a good connection. Worth checking.

Dave

Title: Re: Violent gear change
Post by GeraldineGreene on Jun 27^th, 2006, 12:20pm

Hi ya and thanks to everyones replies so far. I am being led towards a faulty wiring loom however, can anyone tell me where about on the loom to look ie, gearbox end or engine bay?
The other question is, would that also cause a lack of fourth gear?
The speedo works fine and there are no other noises!
please help.......!
New bug eye owner in distress!
many thanks.
PS I think my car is wonderful other than this niggle. :(

Title: Re: Violent gear change
Post by GeraldineGreene on Jun 27^th, 2006, 12:23pm

Thanks Dave, I will be definately checking out your idea later.
Ania

Title: Re: Violent gear change
Post by davem on Jun 27^th, 2006, 12:26pm

Regard "no 4th gear", I presume you have checked the "overdrive" light is not on...on the dash.....and does pressing the overdrive switch on the gear change illuminate this light? If this switch functions as expected, then the overdrive solenoid maybe stuck inside the g/box....or as you say, it could be a wiring loom problem. Check the overdrive function 1st though...as replcing or thouroughly examing the wiring loom..is an "engine out" job.

Title: Re: Violent gear change
Post by fordcos on Jun 27^th, 2006, 12:28pm

could cause loss of fourth also could be caused by faulty vss. loom faults usually found anywhere from the connectors on the drivers side inner wing to the rear of the engine.

Title: Re: Violent gear change
Post by GeraldineGreene on Jun 27^th, 2006, 12:34pm

The overdrive light does function. Is checking the solenoid a big job? Also, is checking the VSS a big job?! ???

Title: Re: Violent gear change
Post by Dave on Jun 27^th, 2006, 12:54pm

Solenoids can be changed without dismantling the gearbox but unless very handy with a spanner this would be best left to a mechanic.

The VSS is just bolted to the side of the gearbox and is simple to change, costs in the region of £55 from Ford. Check the wiring to it first though. Sounds like it, or associated wiring, could be at fault.

Title: Re: Violent gear change
Post by Eric_R on Jun 27^th, 2006, 11:22pm

GG,
Just caught your post about thumping gear changes.
Does the Overdrive light flash when this happens? If so, a Diagnostic Trouble Code is being set, and this can be read by anyone with an OBD lead - this will tell if there's a solenoid fault.

If the overdrive light doesn't flash, then the EECV module has not detected a fault. It occurs to me that if the car sometimes drives smoothly, but sometimes 'thumps' into gear, then it could simply be the Throttle Position Sensor (TPS) gone out of synch. see http://www.fordscorpio.co.uk/obd2scan9.htm for details. The EECV expects a resting value of 16% for the TPS, but it can be put out of synch by pressing the accelerator at keyon - and since the TPS is one of the values used by the EECV to schedule the gear changes it can mess things up somewhat.
If you have an OBD lead you could check the TPS reading yourself, but if not, it would do no harm to force a resynch by disconnecting the battery for half a minute. Make sure you have the radio codes, but if not we can sort that.
If the trip computer, the cruise control and the speedo all work okay it's unlikely to be the VSS, and before you get up to your armpits in the wiring looms it would be best to try the resynch first. ;)
Give it a try and get back to us.

HTH

Title: Re: Violent gear change
Post by GeraldineGreene on Jun 28^th, 2006, 9:12am

Hi Eric_R

Many thanks for your response.

Firstly the thumps occur more often than not, although the change between 2nd & 3rd is generally seamless under normal driving conditions. It also seems that 4th is never selected either!
The speedo, trip & cruise all seem to function normally & the Overdrive light doesn't flash at all. I disconnected the TPS last night, cleaned the terminals and tested the pot itself for a linear resistance change, which also seems to be OK. We have also tried the re-synch procedure twice but there are no obvious changes.
Another observation is that even with economy mode selected she will almost hit the red-line before changing gear (something that my previous 2.3 never did) and when slowing down it almost feels like 1st is being selected too early?

A bit of a mystery I think! :-/

Finally, where can I get the necessary lead to connect to my OBD socket? It seems like it could be a good investment! I already have a basic FCR but is only good for the EEC-IV.

Cheers,

Paul & Ania

Title: Re: Violent gear change
Post by Eric_R on Jun 28^th, 2006, 9:53pm

Guys,
Blast :( I was hoping it was something easy.

The lead most of us use is from http://www.obd-2.com/
and provides for datalogging as well as checking for DTCs.

If you suspect that overdrive 4th is not being selected - on a run confirm this by driving to 2900 rpm - this should be about an indicated 80mph (actually 74 mph) If the speed is lower than that at 2900 then either overdrive top has not been selected, or the Torque Converter Clutch is not operating. At the same speed, press the foot on the accelerator gently. You should see the revs rise quickly as the TCC disengages and only then the road speed increases. If the road speed increases at the same time as the revs rise then the TCC has not been engaged.

Either of these could be because a solenoid has failed - or that the EECV has actually deselected this gear because of another reason. This could be because of a faulty Trans Fluid Temp (TFT) Sensor, (if this is faulty the EECV gets its data from the ECT, so if this fails then it cuts out the TCC), bad data from the MAF etc.

If you could get an OBD lead, or meet with an owner who has one, we could check the TCC actually on the move, check which gears have been commanded, read the TFT and the ECT, the MAF and the VSS for that matter. If the EECV is aware of a problem it will also have stored a DTC - this would probably be a solenoid error and it would show us where to look.

If your car build date (not first registered date) is post June 1996 it is not likely to be a wiring fault - pre that date arnitel wiring was used and it has proved to be problematical on some cars - although mine never had a problem. Ford never did discover why some looms were faulty and others were okay; they switched to Raychem44 to resolve it. An OBD reading will show up a problem with the wiring quite quickly. I could advise you to check the multiplug on the passenger side of the autobox, but it's above the oil pan and quite difficult to get to, so it would be easier to check with an OBD lead that all the data from the sensors is getting to the EECV first. Could you meet with an owner with a lead?

Title: Re: Violent gear change
Post by GeraldineGreene on Jun 28^th, 2006, 10:19pm

Once again Eric, many thanks.
There is alot to take in and with a long journey fast approaching us we are very limited to time, we have taken Friday off to dedicate our time to some investigation. We used 'winter' mode to stop her thumping into first so that is one temporary measure, we will persevere and get to the root of this problem, meanwhile... if there is anyone nearby, (Gloucestershire), that we can go to, to try out the OBD2 then we will be extremely happy!
The car was registered in Feb '96, so the build date must be pre '96.

So off we go again! Ever hopeful!

:-/

Title: Re: Violent gear change
Post by Eric_R on Jun 28^th, 2006, 10:48pm

Guys,
When you have a moment, work through http://www.fordscorpio.co.uk/autogearbox.htm
- or perhaps you already have ...

Title: Re: Violent gear change
Post by GeraldineGreene on Jul 6^th, 2006, 8:39pm

Hi guys and gals

Here is the latest update...

Got distracted slightly last Friday by a strange noise coming from the rear passenger side wheel... bearing, in many pieces!!! Eventually got hold of another one and we have now changed this along with set of rear pads. Total price - £54.00.
Then, thought we made a breakthrough with the gears as we found a substantial air leak due to a fractured T piece below the plenum, fixed and replaced and she ran a lot better, but unfortunately still had the same problem with the gears except for the fact that she now selects top gear when coasting.

So we are a little further forward. Fortunately, and thanks to this forum, we contacted a very knowledgeable young man, (howiedintheplace), and obtained a wiring loom!!!!!! along with several other required parts.

(We would just like to mention at this time, this chap really knows his stuff and was very helpful).

This weeks project - 11am Saturday, car going to garage for an OBD2 scan, we just know that we are going to have to sort out the loom, so Saturday PM, Geraldine is having some slight internal surgery, wish us luck!

Thanks to everyone so far, any more ideas will be gratefully received.

PS Took her to work this morning in the horrendous rain, and guess what?! gears were completely different! Gear changes were almost seamless although she is still not selecting fourth correctly.

Please, please, please keep the suggestions coming...

Title: Re: Violent gear change
Post by Dave2302 on Jul 6^th, 2006, 11:18pm

I'm a retired auto box man with a pre June 1996 Cossie estate. I also need a wiring loom, and can confirm that this will be your most likely cause, as the gearbox oil pressure is modulated electronically, the higher the pressure the harder and later the shifts in rough terms !! On an OBD scan you will likely get a pressure regulator solenoid fault showing. The solenoid is probably ok but as the wiring insulation falls off you get all kinds of resistance problems which causes the transmission to go into limp mode. At this point the pcm is unlikely to command 4th gear. Shame you bought the wiring loom off Dave Howie a few hours before I posted my wanted ad!!! (LOL only joking !!!) Anyway good luck with getting her sorted but I do reckon the loom will be your culprit. Regards Dave

Title: Re: Violent gear change
Post by Dave on Jul 7^th, 2006, 10:15am

I think Dave could have sold that loom 20 times over ;D

Title: Re: Violent gear change
Post by Dave2302 on Jul 7^th, 2006, 12:03pm

Reckon your right there Dave ;)

Title: Re: Violent gear change
Post by GeraldineGreene on Aug 14^th, 2006, 1:17pm

Hi All,

Been really busy & this is the first real chance I've had to get on here, but here's an update.

Took Geraldine to local garage for a scan. One code was logged (number escapes me at the mo) relating to a solenoid problem & when the chap tried to clear it down it refused to go away!. :o
Anyway, decided to investigate the engine loom & found that the TPS wires were completely bare & many others were cracked. So, we removed the loom & I spent about about a week after work replacing each cable in turn & wrapping more cables individually (loom slightly fatter now!) as extra protection.
A week later we were under there putting it all back, convinced of a victory!

Now the annoying bit. Re-started & waited for all the rough running to go away (which it did) & then went for a drive.
Gearchanges are still exactly the same >:( ???
Things haven't changed much over the last few weeks, yet the gear changes during most of the drive to work this morning were the best they've ever been, although they did start to get a bit thumpy after a few miles blast along the dual carriageway.

So still not really any further forwards at the moment!!

Need to get a scan done on the move now & try to find out exactly is going on with regards to gear commands & selection. Can anybody help with this as the OBD II lead kit I've bought seems to be the wrong protocol?

Cheers,

Paul & Ania