Hey guys just a quick question I have a deadspot at 80Kmph, its not all the time only when it wants to be a pain. When i get to the deadspot when it does it. i accelerate and it dont do anything until my foot is pretty much planted then as soon as i get it down far enough the tacho goes right up and gets past the deadspot. i can leave my foot normally but takes a long time to get past the deadspot, its at 80-90kmph the dead.. All leads and plugs have been changed and its still doing it, im suspecting it could be a lifter... Because when i take the leads off a plug on car when running. theres 1 plug that dont really make the motor do nothing when i take it out, it dont hic-cup or anything, it does very very slightly.. but not like it should so if anyone has any suggestions about this can ya please get back to here. needing to get it resolved asap.
get a compression test done to check the basic condition of the engine. also get your base timing checked
Could be a dodgy lead or plug, just because they are new doesn't mean they work. try swapping the crook cylinders plug with another one and see if it still does it, then swap a lead over and check again. Do an error code check as well to rule out ECU related things.
Yeah the leads and plugs could be dud, i just cant see that only due to because thats the reason why i changed the leads and plugs to start with, cause it was that one cylinder that wasnt doing anything when i unplugged whilst running., thats why i changed them to start with, yet its still doing the same thing... does the same thing with the new leads as well as the old leads?
Can you hear a 'put put put' out of the exhaust? May be a burnt valve. A lifter will give a constant ticking and usually goes away with revs.
you could just pull the rocker cover off and see if there are any broken valve springs/rockers. run the engine and see if everything seems to be moving correctly etc
Doesnt go "put put put" Only thing i do notice is that when idling and got the bonet up every now and then the engine shutters a bit more than usual, so when its idling and its moving in the bay a slight bit, the engine then moves a bit more than it usually does, only does it at every certain point when its idling.
could be something as simple as a blocked injector also causing the cylinder to miss etc usethe poor mans stephoscope (long screwdriver) and see if the injector for that cylinder is ticking (an indicator that it's working electrically)
Check the fuel regulator as well, make sure it is holding vacuum, if the diaphragm is split it may be leaking fuel into the inlet manifold. Out of curiosity, was the lead that you took off near the rear of the engine? One somewhere inline with the vacuum fitting for the fuel regulator? If excess fuel is running into that cylinder it won't ignite properly and give the symptoms of a dodgy plug.
Not_An_Abba_Fan: Nah its no-where near the rear of the engine the problem cylinder. its right at the front, its the Front Right side "if your standing in front of the car". so its the very first one on the right hand side
pull the plug out and smell it after you have run the engine for a few minutes. is there a gas smell? is it covered in black soot? or does it look like the other plugs? looks like oyu have afew things to try today, goodluck, let us know how it goes
Checked the plugs to see if there black like you said, and its just as clean as the rest of them cause i took out another 2 and made sure it was the same. so today i might take rockers off and check the springs, lifters and check the valves and see if i can find anything
Hey, ive did most of the following still having no luck at present.. ill tell yas if something changes, and if i find the problem, checking valves and so on today after work this arvie ill come home and get to it. If nothing is resolved i seriously do not know what it is causing the problem, then i will be very confused. ive been around cars and working on them for years and years, never seen a car do this..
to check to see if it's an ignition fault just pull the lead of a plug and fit to an old plug that you need to earth against something. open the plug gap a little and run motor. if there is a spark you know the ignition system is working fine.
Check this vid. well worth watching only goes for a couple seconds tho http://www.youtube.com/watch?v=Thg-w1rkbRA That problem im having with me car is starting to worsen a tiny bit more, i got no idea what it could be, im gonna try the dizy cap this arvie to see if that helps anything. Motors give ya the sh**s sometimes.
it sounds to me not like an ignition or compression/valve problem, dead spot would be more along the lines of fuel delivery issue, and the way he sais that it starts to go again with his foot flat to the floor, the mixture seems to be leaning out around 80 - 90, so i would be checking the fuel pressure regulator/pump pressure and flow, and im not sure if these run a TPS, but if they do, replace that, and it may also be the MAP sensor, it sounds like an electrical issue on the engine managment system, so check all that stuff b4 comp tests n stuff like that, they wont cause 'dead' spots
