Sweetie Pie - (Obviously a Lady!)
I find that sentence curious, as it rings a bell. Can you name or give the road Number, I want to do a search.
Also - do you have any problems elsewhere, either juddering or speed related?
If it wont go over 60 in 5th,sounds like you need to put a turbo on it or rockets!
Its the barton le clay by pass A6 near luton. I have had a head gasket go on one car. An alternator on another and now this. All have been without any warning signs. I would avoid it if i could.
I’m no mechanic, technician as everyone knows. So be prepared to laugh at my thoughts which are:-
There is a wobble which appears at speed (caused by out of balance wheels, worn track rods etc.) and undoubtedly causes drag/resistance, much as climbing a hill. The higher the gear the less torque/power, so in the higher gear you cannot accelerate/hold your speed, the same as trying to climb a hill in high gear. Change down and you can mantain your speed.
So my belief is that if you trace and cure the cause of the shudder the apparent problem with acceleration will disappear as it’s a symptom of the shudder, not a problem in itself.
Additional: My thoughts seem to be much the same as those of Roadster Robbie in post #16.
It’s quite obvious then, it’s the road, the A6.
If that is the case may I suggest avoiding the A12 ,as the wheel wobble will be twice as bad
In my experience a 60mph steering wheel judder has always been wheel balancing.
Why 60mph, I don’t know.
However, it’s unlikley to cause a loss in acceleration.
I did once have a universal joint start to fail on a propshaft, which gave similar issues, but it’s so long ago I can’t remember if I had acceleration issues.
Apologies to OP, However, I had to laugh at that?
Barrie
Its ok i know it sounds silly. Its true though my cars have never broken down anywhere else.
O/K here comes my theory. No doubt it will be considered by some as sounding like the twilight zone, but I’m serious – regardless.
Sweetie Pies opening post said something that aroused my interest, and further comments increased it. While my memory is getting a bit fraught, call it age related if you will, but the facts are there, regardless. Last year there was a documentary on a road in the UK, possibly Yorkshire? – I don’t remember, but many reports of problems on one section of road where different drivers reported problems with different make of car, but always on the same section of that road.
IIRC – investigations showed a magnetic influence in one area that was eventually traced to an RDF
Shack not far away. Whether it was cured or not I have no idea, but that gave me pause to remember the report, regardless as to where it was. On this basis I’ve spent some time searching the net for possible cause, and one thing became obvious – if you look at a map of that link road mentioned, it skirts Luton Airport via a loop, showed plainly on the map. However, determined to track down any possible source, I downloaded a map of Ley Lines in the UK, which doesn’t show any immediate connection between them and the Airport. But another website claimed that there is no valid map of Ley Lines in the UK, nor is there any intention to produce one. So that rules Ley Lines out. Why did I check this? – Ley Lines are reported as being paths of energy, traceable by ‘dowsing’ and from that it’s obvious it will never be possible to produce a complete UK map of the phenomenon. Dowsing will turn up many things, including water, metal deposits etc.
Next step – search for other incidents involving car problems on the road, tried various searches, but none revealed any. I didn’t ask any of the breakdown services, as you can’t expect an answer on a weekend. So – return to the map, which shows that loop round Luton Airport. I PMD’d Sweetie pie earlier today, and asked if the various problems with past and present cars had all occurred on that same stretch – the loop? And she replied “Yes – all of them”. She also said, “It’s happened again this morning, on my way to the garage where I’ve left the car”.
So, that ties it down to the Airport, and loop round going round it. So what could cause all three unrelated problems with three different cars? Listing them below, here’s my possible explanation, though no doubt most will disagree with my thoughts.
Car 1) reported alternator failure = Magnetic influence on alternator that causes it to fail (quite possible IMHO)
2)n Car 2) Reported head Gasket failure = Not magnetic related, but possible intake of aviation fuel vapour, causing heat build-up or mild explosion, blowing the gasket? This would be a rare event, but not unlikely in my mind. No other reason offered.
- Current issue – MX5. Reported loss of speed and severe steering wheel judder.
Two components are close to the road, the ABS sensors and the PCM. Either or both could be affected by a strong magnetic field, but where would it come from? - Ground waves, every signal (even mains electricity) can travel on a ground wave. Where would this come from? An Airport has Radar, RDF, Comms and A/C wiring laying under the ground – approach and runway lights, parking zones, etc,.
Granted, these are not strictly magnetic, but contain a wavelength pulse of some description, and lumped together, a cocktail of pulses with each waveform. This could affect pulses from the cars ABS sensors (which rely on a given pulse each time the wheel moves) and override the normal ABS sensor readings, possibly producing rapid alternate braking on each side, or braking on both sides.
As for effect on the PCM, well, it relies on a fixed scan pulse to complete a full cycle of regular sensor scanning, and if the incoming pulse is strong enough, can effect and override the PCM’s normal scan cycle. This could affect any speed signals it receives from the throttle sensor (TPS)
Most of this will – I’m afraid, sound like Sci-Fi to most readers, but it’s possible regardless, but I can’t prove it. As the MX5 concerned has gone into the garage today, we’ll wait and see if they come up with an answer, if not, then more research is needed. In the meantime I offer this up as a possible cause.
Abbreviations - RDF (Radio direction finder) : PCM (Correct term for a Mazda ECU): TPS (as stated)
Had a late thought (often happens)
On the judder, I’ve had another thought - if the ECU is affected then maybe it’s running on three cylinders, which would also explain the judder, as it transmits right through the body of the car, and everything will judder. This also explains why it wont’pick up speed, so I’m convincing myself now that my theory is right.
It could also affect each cylinder in turn, as the PCM cycles are affected - this would add to the general judder. This negates the ABS sensors being affected, which doesn’t really make sense till you think about it.
On my searches, I cam across a ‘Aren’t we clever’ post from Tarmac construction re the new connecting road in question, so that negates any side thoughts I’ve had about concrete sections, which have a ‘ripple’ effect - bit like driving on hard corrugated cardboard, we had a couple of those around me a few years back. There’s also one section on the M25 where the noise generated is enough to drive me bonkers, and I heave a sigh of relief when I get back to the tarmac surface.
Perhaps there are some British Leyland lines near there?
I’m with Roadster Robbie on this - sticking front caliper. Had EXACTLY the same symptoms.
I wonder. If a caliper were sticking wouldn’t it just cause the car to “pull/drag” in one direction rather than cause a shudder?
No because the excessive heat build up temporarily warps the disc which causes the judder
I meant to say as well it very rare to get the car pulling on the steering with brake drag your symptoms are normally vibration or people smell the hot brakes when the get out of the car.
I have just spoken to the garage. They think it is a slipped clutch and the wheel balance. They are going to road test it and check it over again before they confirm it.
Were your engine revs increasing then without road speed increase ?
And thanks for keeping the thread updated
A bit late but I was going to suggest swapping the front and rear wheels over to see if that helped.
Are they going to go down the same stretch of road?
I know it sounds a bit sarcastic the above but I’m intrigued to find out why on that road, it is a weird event.
For clutch slip take her up a steep hill and put your foot down ( if safe) on accelerator. If engine revs suddenly without an increase in speed the clutch is slipping.