Help with my car?
Answers:
sounds either an electrical problem or fuel. you may have a blockage. have you let your fuel tank run very low or empty recently? if so it will be bits from the bottom of your fuel tank caught up in your carburetor jets.
electric could be anything. ask a garage (that you can trust, not many of them!!) to run a diagnostic check on it, unless it's very old they just plug it in to a laptop and it can show where you cars failing. hope this helps.
Not enough info here to help I'm afraid, but it could be the timing belt/chain.
Could be a blocked fuel pipe?
Could be as simple as the mixture in the carb, you could try tweaking the petrol to air ratio. If it is too rich, it can sometimes lurch then almost stall, this is usually an old car complaint, but can affect anything.
Alternatively, it could be the alternator which designates which spark plug to spark when, if this is dodgy, one or more cylinders may not be firing having the same effect as a duff spark plug.
would help if you told us which car, and when it is jumping
Are you a crap driver? Sometimes the simplest explanation is the right one!
Without stating the make and model it is not possible to guess at what is causing your problem. You state you have asked two different mechanics to look at your problem, and, without success. Why not take the vehicle to a reputable Garage, preferably a dealership for you model, and request that they give you an estimate for adjusting the problem, which may be the timing. If in the UK take the vehicle to the garage which performed the last MOT. That garage should have equipment to tune your engine.
Our ideas will not solve the matter because whatever happens you need a competent mechanic who has the right equipment to diagnose and fix the problem.
What pray is jumping, My Bike used to Jump over the bridge at Aynho until I looked down on a Vauxhall Viva, if this is your problem slow down over hump back bridges.
It is more likely that it is a throttle position switch, this will cause a pronounced jump when going on and off the throtte if you drive gently, otherwise a sticky air flow metering unit will cause stuttering jumping etc but these aint cheap.
Need more info exactly when does it jump
ht leads? might be running lean
need more info realy could be anything from plug leads dissy cap
fuel filter anythg realy?
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