My AU shudders when slowing down

[Tony_4500]

I get a shudder when slowing down, at around 30-40 kph when slowing the rev counter drops to about 200 rpm and the car starts shuddering and wanting to stall. It does it before the brakes are applied and still shudders if I put it into neutral, it does it with the motor hot or cold and is sometimes worse than others. To explain the shudder it's like when you turn the power steering to hard lock with the motor idling, it looses power and shakes the car. Its on straight LPG and has just been tuned and serviced, the problem started as soon as the aircon was regased although I have taken it to another aircon installer and he says the aircon system is fine and not the cause, it does it with the aircon turned on or off although it does seem worse when the aircon is on Max. I have been to my local Ford dealer twice, my local mechanic once, the LPG specialist once, a auto elec and aircon specialist once and I still got the shudders. What next??? Any ideas or thoughts welcome, I just want it fixed. Anyone else heard of anything like this before. Cheers Tony

[JC]

ISC valve needs cleaning.

[GK]

Give it a clean.

Try this link!

http://www.fordforums.com.au/showpos...9&postcount=43


GK

[Tony_4500]

Thanks for all your help, new here but I have owned Fords all my life including a XC Cobra and many Hardtops and F100's. Spent many years driving F350 Tow Trucks in Sydney and Brisbane and just love those old trucks. Have learnt heaps on here tonight, I have put a new battery in the car in the last week so I will be resetting the ECU tomorrow as well as cleaning the ISC. You dont get this much info anywhere else so keep up the good work. the information on here is priceless.
Cheers Tony

[bigjim]

I have had this same problem with my s1 xr6 whenever i disconnect the battery to do some work on it, but the problem goes away after a week or two. Is it the same fix?

[Tony_4500]

I have cleaned the throttle body and the ISC and reset the ECU, still got the shudders, will drive it for the rest of the week and see what happens. All I can think of now is engine mounts or a torque converter?? at a loss here, apart from this one problem its a bloody good car.
Still crying over me beer here,Cheers Tony

[The Monty]

Itll take about 100-200K's of driving to get the ECU to relearn itself, after having been reset. This will make the car drop right down in the rev range, making it fell as though it is going to stall.

[Tony_4500]

I have done over 300 k's since resetting the ECU and cleaning out the ISC and Throttle body. The shuddering is that bad now that the car has started to stall, this is worse when coasting downhill than on level ground. The shuddering usually stops after I hear a clunck in the gearbox like it has just dropped down a gear, the shuddering is now starting at about 60kpm where as before it was 30-40kph. I also noticed that when reversing out the drive in the mornings there seems to be no drive in reverse for a few seconds, I live on a small slope and put the car into reverse and coast down to the road but when I want to reverse a bit more it just revs and then starts to reverse, I have checked the oil level and it was fine but was a bit suspect on the colour of the oil, it was more brown than red but was clear. Apart from this the motor and gearbox both work well with no strange noises, it starts and drives well. At what speed does the torque converter disengage and free wheel when slowing down. My local auto elec didi not have the gear to download the ECU codes and I refuse to go back to my local Ford dealer. Would a gearbox mob have the equipment to check out the codes? and finally solve this riddle for me, may just need a gearbox service. Plan B is to wait for it to break then I would know what was wrong! but this could be the expensive option and wont go there hopefully.
Any help would be welcomed.
Cheers Tony

[AUXRVIII]

This sounds like the torque converter lockup clutch is staying locked. Try driving with the selecter in 3 to see if it stops the shudder.

[JC]

If your auto trans oil is brown, it's buggered and needs a full flush. This could be the source of your troubles. Not enough fluid makes the gears not work properly, and also makes the transmission overheat which kills everything. I would take it to a specialist auto trannie mob.

[Tony_4500]

Well I drove the car today with the selector in 3rd and there was no shudder, well spotted AUXRIII, I also started to lose drive while driving so booked into the Auto mechanic's tomorrow morning to see what the damage is to the gearbox and my wallet. Anyone got a rough idea on what a exchange gearbox is going to set me back, I hear they are a common problem on these so should be plenty of them around.
Will let you all know the outcome, all symptoms pointed to a fuel/sensor problem. Cheers Tony

[Tony_4500]

HERE WE GO AGAIN[U]
I have just got the car back from the Automatic gearbox people, he flushed the system and adjusted whatever needed to be adjusted but the car has still got the shudders, he swears it isn't a gearbox problem. He checked the ECU codes on the gearbox and all was ok, he also checked all the mounts and the drive shaft, he reckons it's fuel related. As for why I lost drive he say's it could of been because of the condition of the oil, without pulling the box apart it was hard to say. His oponion was that the gearbox was in ok condition and he believed it wasn't causing the shudder.
I have just replaced the ISC unit with no results.
What the hell is wrong with it???
I have booked it into a Auto electrician's next Tuesday, he reckons he has the equipment to trace the problem. Fingers crossed.
I will shortly be turning this into a Soap opera, stay tuned for the next episode!
Cheers

[janek]

Stupid question. Have you checked the power steering fluid level? It may need a top up, or may have a leaky hose as 99% of them did at some stage.. Could be big drag on the PS pump. OR the sensor may be faulty and causing it to be on full or whatever the problem may be...

BUT if it goes away in 3rd, auxr may be right, and it could be the torque converter... You sure the auto place put in new 95 type tranny fluid, not dex3?

[Tony_4500]

The Automatic guy has been in the same shop for 20 years and is very well known to the local hot rod clubs, so I guess he used the right oil, he also told me the gearbox in my car was a 1995 model BTR and not the AU gearbox. On another note I have disconnected the ISU altogether and the car is running 95% better with only very minor shuddering, I mean if you weren't looking/waiting for the shudder you wouldn't even notice it. I did not have to make any adjustments to the idle when disconecting the ISC and it runs well even with the air con on max. The power steering was low when I got the car 2-3 months ago and I put in a bottle of stop leak/conditioner to top it up, I have noticed that it does leak out of the top where you fill it but not to bad, maybe a bit overfull.

[JC]

Your ISC is stuffed. I know you said you replaced it already, but the replacement must have been stuffed too. Either that, or the ECU is stuffed when the ISC is plugged in.

[Tony_4500]

What next???
The car has just spent 2 days at the Auto electricians. The ECU scan showed up clear, they then tested every sensor manually and all passed. The ISC was leaking and changed. Now the car not only still SHUDDERS it is also hard to start. Off to the LPG mob for another tune up. It has to be the Torque converter as thats the only thing that hasn't been replaced.
The story so far :
1- serviced at Q Ford twice
2- Tune and serviced the LPG
3- Local mechanic once
4- Auto electrician no 1
5- Aircon expert once
6- Auto gearbox service
7- Auto electrician no 2
This is getting beyond a joke now.

[AUXRVIII]

The fault may not be with the torque converter, it could be the ecu not disengaging the lockup clutch, it is not something that will show up during a self test. A known good ecu will need to be fitted to confirm if this is the cause of the problem. It sould also be the solenoid that is used to lock & unlock the clutch, but I suspect it will be the ecu.

[phorj]

You could always try the TPS (Throttle Position Sensor).

My EL was changing for 4th to 2nd on the Freeways, and shuddering while slowing down at the lights.

I swapped the TPS and it's fine now (though doesn't lockup 4th). I think that could be because it's second hand an I don't know the condition it was in.

Good Luck,

[GK]

What's the state of play with your car now Tony?

GK

[hilly1981]

That sucks champ! Hopefully you will find the source of your problem soon.

My opinion, right or wrong start with the absolute basics first. Then work from there.

Cars are fickle things. Just be careful you aint being screwed by some dodgy mechanics. My dad had a issue very similiar to this and it ended up being the oils levels in the transmission. His EF was locking into one gear, then suddenly changing into another. Also stalling at lower RPM etc...

Best of luck mate. I can only imagine how frustrating this must be for you. Let us know how you go.

[StAndArdAU]

my car has this exact same problem, petrol though not LPG. i've given up trying to fix it

[Tony_4500]

It was the Aircon compresser. I got sick of wasting money and decided to drive it until something broke, and it did. Just after the new year the aircon pump seized, since then the shuddering has stopped. Been driving it around with the pump turned off for a few weeks and it's a pleasure to drive, it is in the shop as I type this getting a new pump fitted. Also it was hard to start even after 2 visits to the LPG mob, whilst hiding from my inlaws on Xmas day I played around with the LPG converter and fixed the problem myself. when the key was turned on one solenoid would click on and then off after 2-3 seconds. I pulled it off and cleaning the rust and dirt of it, when next turning on the key the solenoid clicked for 2-3 seconds but there was also a hissing sound of gas going through to the throttle body and the car started first go. Even though the solenoid was clicking it wasn't giving the motor a shot of gas to start it. Like a new car now, every time I start it now I listern to hear the shot of gas before starting, if I don't hear it I turn the key off and on untill I hear it then I know the car will start first time.
Also the aircon man just rang and my car won't be fixed today as the aircon pump he was sent was for a series 2 and it will not fit a series 1, something about the length??.
Looking forward to enjoying my car for once, been a long road so far. Now I just need Summer to turn up so I can use my aircon, Summer has been a bit of a dud up here in Brisbane so far.
I hope my muttering's can help someone else with their problems.
Cheers Tony

[blackers10]

congrats on the find mate!!

the only wierd thing i found with my aircon being on.. is it sorta gives the car a ~200rpm rev every 30 seconds or so which is annoying when sitting in traffic as people probably think i want to race them or somthing LOL
as i have a 2.5" exhaust you can hear the rev quite clearly

does or did yours do this?

[GK]

Hope its all sorted to your satisfaction soon Tony!

One question though. Why would the shuddering go away when the car was in 3rd? Is it because of the higher revs?

GK

[Mechan1k]

The cold-start solenoid doe get gunked up with wax as you found.
Mine failed one day .... it has been bypassed for the timebeing though ... as it was flooding the engine on start-up.

Works better without it now than it used to. Strange thing.

[Belial]

Hi guy's for whats it's worth I had an EBII S pak with a similar problem and it was caused by the earth lead that bolts to the engine block.
The bolt had become loose and as soon as it was tightened up..... Blamo, A car I didn't want to set fire to anymore!!!!

[Tony_4500]

It's Back, after 2 days of driving the shudder has returned. it's only when the aircon is turned on though. not as bad as last time but still annoying. Has a new aircon pump and receiver/dryer fitted and the system was flushed.
Bloody car!!
Cheers Tony

[scottc]

Tony, how much did your aircon cost, pump and all?
Sorry to hear it's still playing up.

[Tony_4500]

$500.90 all up, $420 for parts and $80 for labour. I really thought it would be dearer, the aircon has never been so cold and I actually find myself turning it off so I can warm up a bit.
Cheers Tony

[Tony_4500]

Ok...had a look at the earth lead and it was in a pretty sad way. Have replaced it without any results. Even though it wasn't the problem it looked like it needed replacing. By the time I track down the problem I will have a brand spanking new AU changing one part at a time!!!!
I am now starting to lose drive in D only when accelerating. When I knock it back to third it comes right again. If I accelerate while driving at around 80km/h and put my foot to the floor it kicks down 2 gears and then loses all drive. Again it can be fixed by putting it into third. It drives ok and drops down through the gears it is just when it is in drive (D) after the car has warmed up.
Somebody mentioned a while ago that an O ring in the torque converter was worn and it could be causing the shudder that I have had for months but I also have been told it could be a faulty solenoid. What do you reckon????
6 weeks ago the gearbox was fully serviced with a full oil flush etc and the guy said all was OK but they can't check the torque converter without pulling it all apart ($$$$)
Don't know which will happen first, mental home or bankruptcy! ...or divorce hehe.