Engine idle too high

Never seen this vehicle so i cannot really comment here but as its so old their shouldnt be a lot of fancy electronics unlike a modern vehicle but i would be inclined to look at any rubber hoses connected to the inlet manifold like the brake servo and the engine breather or a take off to operate the flaps on the heater/AC unit inside the car although it might just be cables and not vacumn operated flaps ,Dont think its anything to do with the gearbox but as iam not used to this car then i cannot really say or know but i would look at the engine intake manifold first

Sorry guys i was late with my feedback... So here it goes.. I have no check engine light.... Currently running the stock tune as well.. The car has no tps, pcv or egr valve.. It is all controlled by the electronic throttle body which i recently cleaned but didnt help with my problem. I ordered a new fuel pump as well, just didnt get the chance to install it yet. Cant change the fuel filter as it is builtin within the pump. However, shouldnt the fuel pump or fuel filter cause engine stalling, bucking and hesitation? I doubted the fuel pump could be causing this since the problem only occurs at idle. By the way, there is no missing on any of the cylinders.

h0m0

I suggest a second opinion would be in order as everything he did for the tune up was not altogether necessary. I consider that as the car was running ok before I would not touch the carby other than to fine tune the idle mixture to emission requirements. Any problems with the distributor cap would have showed up as a miss and the rotor button would have to be really bad but again as it was running ok. My policy is don't touch what ain't broke.Power valves in carbys are there to give extra fuel when the vacuum falls off under acceleration and do nothing else. To accommodate a bigger alternator more adjustment on the idle mixture screw would be necessary at idle but as alternator barely charge at idle the adjustment would be little. The low compressions may be from pumped up hydraulic followers and I would discuss that with the original engine builder as to what hydraulic units he fitted. but again if it was running ok before what the hell. Yes get a second opinion for sure from the engine builder.

Sounds as if the A/C Compressor has issues with the clutch/shaft locking up.... the blow off you heard was probably the pressure relief valve allowing an over charge of freon escape the system....however if the A/C system has a compressor problem or a clog that condition will also happen....can you have someone put a set of high/low gauges on it just for safety sake to be sure it is not developing too high of a head pressure...that would be my recoomendation....if the compressor locks up the belt can be thrown off causing your vehicle to require a tow/repair on the spot.

The noise is caused by the engine running on after the ignition is shut off. It makes noise because the pistons are rattling in the cylinders from incorrect timing. This has nothing to do with the mechanical or electronic timing of the engine. The engine runs on either because of hot glowing carbon deposits in the cylinder head or because the engine was shut down when it was running too fast. Sometimes the carbon can be literally blown out by running the engine at high rpm for a short time. Put it in second gear and run it for a couple of miles on the highway. If this does not work the heads will have to be removed and the carbon cleaned out manually. The shut down when running too fast problem can be caused by the idle being set too high or by shutting the engine off before it has reached idle speed. If you can adjust the idle speed try reducing it. If not always hesitate before shutting the engine down to let it reach idle speed. Good Luck!

it will idle high with air con on and revs will go up and down try turning air con off it that fixes it then there is no problem

check if went from a V6 TO V8 need power two more cylinders

weeeeiiirrdddd. i have a 2001 hyundia elentra gls, and my third cylinder is misfiring as well. my car also revs constantly on idle and in between shifting. it will flutter between 2-3000 or it will just stay at 5000. i replaced my plugs and wires to no fix with my cylinder. autozone also told me that it sounds like my throttle position sensor needs replaced, but every part they try to sell me will not fit and they swear up and down this is the right part...

The high idle is caused by the choke and the high idle on the carb. It is working normal and you do won't to warm up this motor before going. When it is warm and you hit the gas it activates the choke pull off to bring the idle to normal. Your mechanic is used to fuel injection that will control the fuel/air mix according to temp. I still let my injected cars warm up so the oil can thin a little. If you jump on the highway with cold thick oil it can all wind up in the to of the motor.