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        General >> Problems >> Cleaned MAF but no change in 'box.
        
(Message started by: Seans_Dad on Apr 27^th, 2008, 11:02pm)

Title: Cleaned MAF but no change in 'box.
Post by Seans_Dad on Apr 27^th, 2008, 11:02pm

I took the MAF off the car this afternoon, in the hope that a clean up might cure my auto box shifting problem.
Upon inspection, the sensors were not too bad, looked quite clean in fact. I decided to clean it anyway, as per the instructions I found elsewhere on the site, and sprayed in some carb cleaner a little at a time for about ten minutes. I also checked the state of the air filter, it wasn't too bad, but not brilliant, so I will change it during the week.
Once the MAF was re-fitted, I took the car for a run, but no different.

This is what happens:
Start up from cold, and all gear changes are smooth up and down the box, but once warmed up, the up shift from 2nd to 3rd, is a bit jerky, and the revs rise a bit just before the change. But if I ease off the throttle slightly just before the gearchange, it is smooth, as it should be. It only does this between 2nd and 3rd gears, all other gear changes are as they should be, and the overdrive works fine too. I've checked the fluid, and this is a nice red colour as it should be, and not brown and burnt looking.
Is there a gearbox fluid filter fitted to these cars? I wondered if it might be causing a blockage and not letting the fluid flow properly.
I can live with the 'box the way it is, as it's not a violent gearchange, just a slight rise in revs and then a jerk into 3rd gear.
This has got me scratching my head :(

Any ideas?? And will it mean spending alot of pound notes? :) :(

Thanks.

Dan.

Title: Re: Cleaned MAF but no change in 'box.
Post by stevie on Apr 27^th, 2008, 11:54pm

i,v got the same problems as you describe i,v cleaned the maf too but same however i feel that the maf could be faulty so i,m gonna change it the box has got a filter in the box sump i had mine changed along with the fluid nd things were fine for a while however as you describe all is well till it heats up then gremlins, good luck

Title: Re: Cleaned MAF but no change in 'box.
Post by Octavian_P on Apr 29^th, 2008, 9:19pm

My box on the cossie had the same trouble, a slippage between 2 to 3rd gear. I did a partial oil change and added and extra oil cooler. It did run great for some time.

Title: Re: Cleaned MAF but no change in 'box.
Post by Seans_Dad on Apr 29^th, 2008, 11:35pm

So you reckon an ATF fluid and filter change might cure it? I know with most auto boxes on ANY car, the first sign of trouble, change the fluid and filter, been there and done that with my 2nd Jag, ended up changing the gearbox, and I don't fancy doing that again....... :(

Thanks for your thoughts, can anybody else possibly shed some light? ;)

Dan.

Title: Re: Cleaned MAF but no change in 'box.
Post by TiberiuS on Apr 30^th, 2008, 12:12pm

Hi. Not sure if this helps but I was looking through the Ford T.I.S the other day, it lists both the VSS (vehicle speed sensor) and another TSS (transmission speed sensor) attached to one of the planetary gearsets inside the box.

Now this is only a stab in the dark but symptoms of the TSS failing are listed as rising revs between shifts and thumps into gear, no idea if you can get at the TSS without stripping the box but it's worth looking at. I'm guessing it should set an error code if the two signals are wrong, not even sure if the Scorp auto can set DTC's?

Regards, Bruce.

Title: Re: Cleaned MAF but no change in 'box.
Post by solarpanel on Apr 30^th, 2008, 6:38pm

could also be the servos in the box being slow to move.

Title: Re: Cleaned MAF but no change in 'box.
Post by Seans_Dad on May 5^th, 2008, 7:45pm

Driving the car over the weekend, I've found that driving around town, the 'box changes from 2nd to 3rd as it should do, it is only when I press hard on the throttle to accelerate that the revs rise and then it jerks into 3rd from 2nd gear, or if I ease off the throttle just before the change up, there is no jerkiness or rising revs. Could this be the VSS or TSS as TiberiouS mentioned and is it an esy DIY job to do?
I'm still very pleased with my car, and I can live with it as it is, but I don't want to leave it like this for ever in case I do more damage to the 'box.

Thoughts anyone? :)
Cheers.

Dan.

Title: Re: Cleaned MAF but no change in 'box.
Post by Octavian_P on May 5^th, 2008, 9:27pm

VSS is easy to change, just jack up the car from the behind, remove heat shield and expose the rear end of the box and the VSS fixed with one screw to it. As for the TSS if i remember correctly it's a sensor in the autobox, so it will be a major job.

Title: Re: Cleaned MAF but no change in 'box.
Post by Seans_Dad on May 5^th, 2008, 10:04pm

on 05/05/08 at 21:27:39, Octavian_P wrote:

Thanks, Octavian :)
The VSS sounds simple enough to do.
When you say the TSS is in the autobox, and that it's a major job, is it accessible by removing the sump pan??
I can tackle most things, having done a complete gearbox change on one of my old Jags a couple of years ago(by myself, not to be recommended) ;D

What sort of prices do these sensors sell for?

I am right in thinking that Haynes don't do a workshop manual for this car, but is there any other form of workshop manual available to me, whether online or a CD Rom perhaps?
Cheers.

Dan.

Title: Re: Cleaned MAF but no change in 'box.
Post by TiberiuS on May 5^th, 2008, 11:46pm

on 05/05/08 at 21:27:39, Octavian_P wrote:

As for the TSS if i remember correctly it's a sensor in the autobox, so it will be a major job.

Yep, apparently the TSS is attached to one of the gearsets so probably deep inside the box. The PDFs are on the main site, have some exploded views...they might show the position of it.

Only mentioned this straight as I read it from the manual, it might be a million miles away from your problem. There's a tonne of info on the main site, service manuals and everything. Go to the 'site map' and you should be able to find quite a bit of info :)

Dan, sorry for OT but that 'box you changed, was it a ZF 4hp? What was the mileage? I've changed the fluid in mine, TBH though, that box is my least favourite part of the car. I've driven a BMW 540i which I believe has the same box but I don't think it likes the extra torque on the AJ16. It runs and shifts fine but doesn't feel as robust as the turbo hydra in my old XJ12 :-/

Regards, Bruce :)

Title: Re: Cleaned MAF but no change in 'box.
Post by Simmo on May 6^th, 2008, 6:44am

This (http://www.fordscorpio.co.uk/autotrans.htm) is what Bruce is referring to. ;)

Title: Re: Cleaned MAF but no change in 'box.
Post by TiberiuS on May 6^th, 2008, 5:45pm

That's the one. Cheers Mike :)

Title: Re: Cleaned MAF but no change in 'box.
Post by TRACEYS_LIMO on May 6^th, 2008, 8:58pm

before going to lots of trouble taking the box apart, you have not changed the maf only cleaned it. my box started playing up 18 months after having it completley reconditioned, i went back to were it was rebuilt and had it tested no fault was found, replaced the maf the faults went ;) the old maf looked fineafter cleaning but still did not work right. hope this helps

Title: Re: Cleaned MAF but no change in 'box.
Post by Pegasus on May 6^th, 2008, 9:22pm

on 04/30/08 at 12:12:53, TiberiuS wrote:

I'm guessing it should set an error code if the two signals are wrong, not even sure if the Scorp auto can set DTC's?

Regards, Bruce.

I think it will set codes if it's failing - also looking at the "Enhanced" data can pinpoint problems. A scan could also shed light on the MAF as possible source. So get a scan if you can.

HTH

Paul

Title: Re: Cleaned MAF but no change in 'box.
Post by Seans_Dad on May 6^th, 2008, 10:06pm

on 05/05/08 at 23:46:28, TiberiuS wrote:

Dan, sorry for OT but that 'box you changed, was it a ZF 4hp? What was the mileage? I've changed the fluid in mine, TBH though, that box is my least favourite part of the car. I've driven a BMW 540i which I believe has the same box but I don't think it likes the extra torque on the AJ16. It runs and shifts fine but doesn't feel as robust as the turbo hydra in my old XJ12 :-/

Regards, Bruce :)

Hi bruce, yes, the Jaguar XJ40 3.2 AJ6 was fitted with the ZF 4HP22 autobox, also fitted in the 5 series BMW.
They are actually quite bullet proof, but my problems started at only 73k when I changed the ATF and found shards of plastic in the sump pan and filter :( I was told it could be the torque converter, but decided to change the lot anyway "just in case". The better autobox was the ZF4 HP24E, which is basically the same box, but electronically controlled, and fitted to the 4 litre XJ's.

Back on topic :) Thanks all for your advice and links, very helpful indeed. Traceys Limo has really got me thinking about the MAF now, and maybe I should start with the simple tasks first. I will try a known working MAF and see what happens. ;)

Dan.

Title: Re: Cleaned MAF but no change in 'box.
Post by TiberiuS on May 6^th, 2008, 11:15pm

Hi Dan. Mine's a 4.0 Sport so has the 4HP24, thanks for the info though :)

You can unplug the MAF to force the ECU into preset values, see if it improves the shifts. Depends if you can get a cheap working MAF to try :)

Regards, Bruce.

Title: Re: Cleaned MAF but no change in 'box.
Post by Seans_Dad on May 7^th, 2008, 10:41pm

on 05/06/08 at 23:15:10, TiberiuS wrote:

Hi Bruce.
Can I do that then?? :o Leave the MAF unplugged? Would it not cause damage to the ECU? I will try it if you think it might work, and I'll let you know. ;D

Dan.

Title: Re: Cleaned MAF but no change in 'box.
Post by TiberiuS on May 7^th, 2008, 10:46pm

Hi Dan. Nope, no probs, might make the car run/idle a bit lumpy though, but won't hurt anything :)

Bruce.

Title: Re: Cleaned MAF but no change in 'box.
Post by Seans_Dad on May 7^th, 2008, 10:54pm

Ok Bruce, I trust you!! ;D ;D I'll give it a try.

Dan.

Title: Re: Cleaned MAF but no change in 'box.
Post by Seans_Dad on May 11^th, 2008, 5:04pm

This afternoon, I disconnected the MAF, as per Bruce's recommendation, to see what difference it made to the 2nd/3rd gear change.

Well, nothing really, the revs still rose slightly before changing to 3rd, but this only happens when foot is hard on the throttle(NOT kickdown). there is no "surging or rising revs when driving at slow speeds, or "coasting", and when braking to a stop from top gear, the gearbox is smooth.

Bruce, you said the engine would run a bit lumpy on tickover etc, but it didn't, it was still running smoothly.

From this I have come up with two possible causes:
1) The MAF fitted is faulty and needs replacing
2) There is nothing wrong with the MAF and my problem is elsewhere, ie the VSS or TSS.

Perhaps I should next try a "known working" MAF, and then see what happens.

Any ideas?

Cheers,

Dan.

Title: Re: Cleaned MAF but no change in 'box.
Post by TiberiuS on May 11^th, 2008, 7:07pm

Hi Dan.

Engine management in the Scorp is similar to the X300, they're both mass airflow type and you can unplug pretty much anything and send the ECU into preset data. Of course you don't want to unplug loads of stuff and then storm it down the motorway but unplugging a sensor and taking a gentle drive half a mile down the road won't hurt it.

TBH the first thing I'd do would be change the fluid/filter, unless the box is seriously on its way out then it can't hurt, wish I'd done mine before I went for the recon. What would be great would be if anyone is near with a working 2.3 and some laptop software, you could change a few parts over and get some data. The software reads the MAF airflow directly, IIRC it's in grams/second...should be pretty low at idle then rise with revs, more for heavy throttle when the throttle butterfly is open and far less on overrun.

A scan would also tell you whether there's any codes elsewhere, probably kill my theory about the TSS too ::)

Try another MAF by all means, I'd be thinking that if the fault doesn't change with it disconnected then it's not the culprit. But then I'm happy to be proved wrong :)

Regards, Bruce.

Title: Re: Cleaned MAF but no change in 'box.
Post by Seans_Dad on Aug 20^th, 2008, 10:22pm

Major thread ressurection!!! ;D ;D

This week I finally managed to get hold of a replacement MAF, not a brand new one, but a known working one.
The result.................no change :( still surges on the change up from 2nd to 3rd, and when kicking down from 3rd to 2nd.
All other gearchanges are as they should be, smooth and unnoticable.
The only other thing I have noticed, is when moving the selector from Park to Reverse, or Drive to Reverse, or Neutral to Reverse, there is a short delay of about 1 second, before it engages reverse. Is this another seperate issue, or is my 'box on its way out??
I have 5 litres of ATF fluid (DexronII) in my shed, where is the best place to obtain a new filter & 'O' ring? And how much can I expect to pay?
I still reckon my fault lies with the TSS though, but this looks like a major job.
All suggestions gratefully received :)

Dan.