doomtoo

I'm trying to figure out what in the world happened... I changed the plugs - I followed all directions I could find, but my car is running real rough after changing the spark plugs. I mean, the exhaust is literraly going "putt-putt-putt"!
What could it be? How can I tell which cylinder, if any, is misfiring? I got NGK coppers, and although my old ones have detonation on them(and a bit wore down), I guess they didn't really need to be changed. But the number on them is the exact same as the ones on the coppers. But how can I find out what is causing my car to run like an old bus?

DA-MAX

iTrader: (10)

what condition are your wires in??

and you got these from Nissan??

doomtoo

No, I got the spark plugs from an import store, but they are NGK. The spark plug wires seem to be in good condition, no cracks or anything on them.

DA-MAX

iTrader: (10)

well are the plugs gapped correctly for the Maxima?? if not thats your prob right there most likely. its best to buy direct from Nissan since the plugs are pre-gapped!!

doomtoo

No, I gapped them, gapped 'em good, I did
I actually checked that again - gapped the old spark plugs to see where they were(between .044-.045), and I had all mine gapped at .044, so that wasn't it. But reading some threads, I think one of the spark plugs is dead or a bit bad. But how can I check each one?
kvzeyde in another thread said : But is it safe to unplug a spark plug while the engine is running? wouldn't that cause the major damage to the electrical system, having all plugs fire, and all of a sudden, one stop, maybe even in mid place?

DA-MAX

iTrader: (10)

its safe! just don't touch any metal while you do it....just be careful I've gotten shocked before while doing this, scared the hell out of me

dat_nomad

That explains the hair

DA-MAX

iTrader: (10)

LES!!!!!!! holla at me sometime man...where you been??

Nismomaxt

Check your wires!!!! Sounds like you may have one switched i.e. two going to the wrong plugs!!!

adamis

I'm not real sure but I thought I remmber reading another post a long time ago about someone else having problems with copper NKG's. Does anyone else remember something about this? I'm not to sure why copper would make a difference.

doomtoo

Nah, I did them one by one
What I just spent the last couple hours doing, was removing them one by one, and checking to see which one was bad - still a problem. Any unplugged(the wire), the car runs worse, and it's not the spark plug completely broken - it's just one of the cylinders(or more) are missing every 5th or so time. I think maybe I don't have them tightened enough/ have them too tight.(just a guess from reading some other things, and some with the old spark plugs didn't help to much either). I think I may have to buy a torque wrench. Where would be the cheapest place to get one? Home depot or an auto store?
(and how many lbs/torque should it be?)

doomtoo

So do you think the torque wrench is a good idea? I couldn't really "hand screw" the plugs in, so I used the wrench, untill it stopped being real easy, and according to the instruuctions of the plugs box, I gave it another 1/2 turn. I mean, after taking out two of them, then replacing them a bit later, the car was running a little strange, so do you think that would happen is they're not really screwed tight enough?

DA-MAX

iTrader: (10)

I don't think you really need one, but when I do mine now I use a torque wrench(I think ~14lbs +/- for the plugs)

I got my wrench off Ebay for $20(100lb, click type), brand new, very good build. but since you need yours NOW, you can try Home Depot, but be ready to put some $$$ on it, maybe $40-50 I think for basic DIY jobs 80-100lbs will do!

SamTJones

The best way to trouble shoot the ignition is to start at the dist cap and work outwards. Check the wires at the cap and make sure their clean and free of any crap. Make sure they are pushed all the way in. Next make sure all the rubber plug caps are on straight and pushed down all the way to seat the metal cap on the plug end. As to the correct torque on the plugs, when a torque wrench is not available you can use the three finger method. Lay three fingers across the rachet with you first knuckle at the handle,slightly curled over. Pull the wrench with the 3 fingertips only. When you can't pull any harder because your finger tips will not hold you have reached about 14 ft lbs, perfect for your plugs. I used this trick when I raced Motocross. The last thing to look for is possibly a cracked plug. Some times the deep socket dosen't fit straight on and will crack the porcelin on the plug. Two other items are the condition of the wires and the cap itself. If the wires need to be replaced get OEM (Factory) type, I have been down the aftermarket road and got stung real bad.

Well theres my 2-bits, Sam........

doomtoo

Ok, thank you, I'll try this. it's just it could be so many things(running thru my mind). I bought them at BAP auto parts, one might have been bad. But then, when I took out some of my spark plugs the first time I tried, the car was running rough, so I put the originals back in. Still running a bit rougher than usual(clue that it might be the way I put my spark plugs in[not tight enough? too tight?]) And then I switched out all my plugs with new, now it's running pretty bad, took it to checkers,(free help), guy looked it over, said they are all firing(but it's not a sure fire answer), but this becomes obvious after listening to exhaust, it'll run fine for a few seconds, then "cough, cough, cough", one or multiple plugs aren't firing some of the time. I put half old spark plugs back in, still coughing, less though, but right afterwards, I could really see the exhaust, even though it wasn't that cold out. SO I think it's probably something I did while installing them,(pulled a hose or something), or they're not in tight enough, or something else(the caps all snapped on, and they're firmly attached at the distributer). It's tough for me :L
I guess it's try to elimate things one by one, bnut even with that, I'm stuck with like 4 possibilities that I can't limit, and it could be multiple ones!

dat_nomad

Hiding, working on my album. I just moved and my car is in the $hitter (what else is new). I'll call a you and give you my new cell and crib #.

arges

I'm had the same problem after putting in my new plugs. Yes they are nissan, yes I got them from the dealer, so the problem is not the plugs. After wiggling the sp wires, the problem curred itself.

Now after mess'n around with my the 1, 3, 5 fuel injector harness, I'm getting the same poor performance again. I replaced (e.g., soldered in) new 1,3,5, injector harness connectors but I still have the poor performance.

I think the smoking gun is the way that the 1, 3, 5 sparkplug wire to sp connection are loose. How can I tighten the contacts in the sparkplug wire so that the fit snuggly agains the spark plugs? Needle nose pliers can't get inside the rubber sp cover. Can I squeeze (with pliers) the outside of the rubber sp cover to make a better connections?

Thoughts, anyone?

Stephen

BTW, anyone want to buy some used, beat up engine mounts?

phat

Why would we want to buy a used and beat up engine mounts

arges

Some people want to pore their own mix of polyurathane (sp?) in the engine mounts instead of OEM.

Stephen

doomtoo

nah, called up mechanic - said that it was probably too much antiseize on the plug treads, so I bought brand new plugs, and it helped a bit, but it's still kinda nasty... I've driven over 100mi since then, but it's still doing it, could the anti seize still be in the chambers?

kingrye

dude i just tryed to put on a set of ngk wires and having same problems never touched the spark plugs but i think i might have loosened one because it is miss fireing. i can hit the nuber 2 wire and it make a pinging nosie, i think it is loose im going to try tighting it cause i put stock wires back on a still doesnt run right