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View Full Version : Tune up.


jdmdrft
08-05-2008, 11:06 AM
Ok so i just started driving my car yesterday as it was my birthday yesterday. Anyway. I took it to the exhaust shop and had an exhaust made as the old one was beat to hell. The guy told me it was skipping. i assume this means that it isnt firing on all cylinders at the same time? so do i need to replace the spark plug wires distrubitor and stuff? the car has 160000 miles so i assume there will be problems. is there anything else i should look for? the motor shakes super bad all the time. Like if im stopped it shakes the whole car. Any advice on what to do is appreciated. Thanks.

h22speed
08-05-2008, 11:33 AM
well the first thing you need to do is go by process of elimination. figure out whether its the engine not getting any fuel or spark.

1. while the engine is running, pull each spark plug wire from the plug to eliminate which cylinders are firing good. when the wire you pull doesnt seem to do anything to the idle, you have your problem cylinder.
2. next inspect the plugs. oil on the plugs are bad, as is gasoline. extremely dirty plugs may signify a problem.
3. if its not the plugs, then switch the wires between the bad cylinder and a good one to see if the wire is bad. remember to switch the wires on the distributor to the correct cylinder as well, dont just start moving shit around. after you switch the wires (with the car off of course) start the car again and perform step 1. if the cylinder changes say from cylinder 3 to cylinder 4, your plug wire is bad. replace it ($15).
4. if its not the plugs and not the wires, check your distibutor cap (after you have returned the wires to thier original positions of course). if there are lines going from one electrode point to another, you have arcing, and your distributor needs replaced. might as well replace the rotor in there as well. ($20 together)
5. if its not any of the above, next you will have to check your fuel injector for the problem cylinder. you can find various articles on how to test them, or if you have money, just replace it ($50). again there are articles on how to do this yourself to save money on labor costs.
6. you can perform either a compression test before step 5 or on step 6. low compression in the cylinder means either a) your rings are fried and will need to be rebuilt, or b) your valve is burnt and you will need headwork done. if you start your car cold and go up to the exhaust right away, put your hand on the tip and if you feel a faint sucking, it may also be your headgasket( which i doubt). if you blow a head gasket, youll know it fromt he backfiring and your coolant looking like vanilla pudding.
7. its pretty much by process of elimination starting with the easiest to hardest (costliest). i just replaced my fuel injector this morning on cylinder 3 because i was experiencing similar issues. they get dirty and clogged over time and i can tell a difference right away in the smoothness of power once replaced. gas milage should improve slightly as well if replacing all 4 (recommended).

im sure i said something wrong so anyone feel free to correct me. one thing that will save you money is learning how to diagnose and work on your own car and the internet is a great tool, use it, search it, dont just ask a question and expect everyone else to do the work for you. good luck in fixing your problem, and drive safe now that you have your car

jdmdrft
08-05-2008, 11:51 AM
Thanks man. turns out i have a bad spark plug wire so im just getting all new wires, rotor and everything. thanks alot though.

axiomatik
08-05-2008, 12:46 PM
replace the fuel filter while you're at it if you don't know how old yours is.