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Wondered if the more petrol minded webmasters among us might be able to diagnose this problem.
Symptoms: The car 'stutters' when the engine is cold - it feels as though it is in the wrong gear - almost like a kangaroo jumps - however the revs are high - tends to be more obvious in low gear but can be felt in high gear on steep hills - has been like this for 3 weeks with little deterioration.
any suggestions? It'd be good to have an Idea of the causes before I take her in...
This happened in one of my old cars - not so fun when pulling out onto a fast main road and it just... doesn't... want... to... go.
I agree with the diagnosis above (as best you can on a forum rather than in a garage ;)) - the fact that it does it when cold definitely makes spark plugs first port of call.
Other than that, need to know if it's a mechanical or electronic distributor.
TJ
Its a deisel
You could try using some fuel system cleaner, usually you add this to the fuel tank when you fill up.
Another problem couch be the engine coolant temperature sensor. This detects the engine temperature and sends this information to the "brain" by default most sensors when they fail will send an optimal reading to the brain so that the car will still run effectively through it's operating temperature range. But if it fails you can have problems running from cold.
The obvious other checks spark plugs for condition and gap setting, plug leads and distributor/ignition module.
Also give the air filter a quick check, not likely to cause a problem this severe unless it is really chocked up, but if you don't get enough air pulled through then the fuel mixture will rise, because the engine management is already increasing the fuel percentage at cold, a blocked filter can really mess with the mixtures.
Good luck.
what does a smokey exhaust on start up mean? It sometime smokes at othertimes but mainly and quite badly when you start it.
I don't know much about deisels, but on a petrol car that indicates oil is getting into the combustion chamber, and that can mean the cylinder rings or valve guides are worn. I would think a deisel is the same - it's still oil getting into the combustion.
When an engine is warm, parts of course expand, sealing off any "gaps" letting in oil. So my gut instinct says it's the rings.
I'm no expert, just used to muck around a lot with old cars when I was younger so have pulled the odd engine to bits :)
TJ
If you stop your engine then restart it a few mins later you will probably not notice it as muck, it only becomes a problem when the car has been sitting for a while, for example parked overnight. During this time oil will have seamed through the worn seals and some will have accumulated inside the cylinder.
Is it s turbo diesel?
Mack.
The car has recently had an oil change, new air and oil filter and has been getting worse ever since.
There are a few other thighs it could be. A compression check will help a mechanic make a diagnosis.
Mack.
Last tuneup I had cost $460, and that was a simple plugs, wires, and basic distributor electronic parts. I will never go to a mechanic again, I will junk the car first. A simple tune-up with plugs and wires will run you about $40-$50 in parts, and $20 for a manual on how to do it.
As said when you remove the plugs observe their condition (another point at which you rely on mechanics honesty.) They should all be in similar condition, the best being a brownish dry deposit, sometimes the electrodes showing slight signs of wear. Worrisome is black oily deposits, powdery black carbon and soot, wet gasoline-smelling deposits (unless you've just tried to start it unsuccessfully)or any kind of major distortion or extreme decomposition of the electrodes.
Oily deposits indicate some sort of leakage of oil into the combustion chamber and are usually accompanied by smoke, but sometimes not. This is very bad and you don't want to know what it means. Gassy deposits indicate leaky injectors or valves, the latter being almost as bad as the first.
As was said, oil deposits mean some form of leak..
They should be a light brown colour.
If they are dry...
black = the fuel mixture is to rich
white = to lean.
Check for any evidence of cracks on the ceramic area, this will lead to loss of tension and poor spark.
If all this fails to point out the problem take it to your dealer and ask then to run a fault code reader test. Generally this will cost one hr or labour and will identify any system errors that have been logged by the cars electronic brain.
You can buy the software and connections to use your laptop as a diagnostics machine, but for a one off job you're better just taking it to a garage and having them run a test.
Mack.
This would have been my first guess, but ignition / distributers have more problems when hot then cold. Sorry, I'm counter culture here.
Spark plugs - could be fouled, but that's only a symptom of the real problem.
My first guess - bad oxygen sensor / bad air flow sensor.
My second guess - leaking head gasket that's fouling the spark plugs.
