isit electronic fuelinjector?

Question

new spark&wire roughidle,hard to start,but highspeed good,have spark when pull wire any suggestions,thanks

Answer 1

What is the year, make, & model of your automobile ?

Answer 2

Look for leak in inductiion maniflod. If enough air "bleeds" through, it will upset the air/gas mixture to the point that the cylinder won't get proper "charge" to give you full power to that cylinder. When the engine is running faster (in fact the faster it runs) the more near "regular" mixture will occour, -thereby making the cylinder operate evenly with the rest. Look around the intake manifold "mating area" at that one cylinder. If you spray a small amount of ether around the connections to block there, - you will hear the engine "pick up" that cylinder as the ether mixes with gas, - rather than air! If the leak is big enough, you might even be able to hear a "sucking sound". If you can actually see the leak, you might be able to clean it up enough (if you can get to it) so that; you can seal it with Permatex RTV gasket sealer, - let it set overnight, and hopefully everything will work ok. If you get enough on outside, (working a little into "crack if possible) vacuum won't pull it through, as pressure is trying to pull large amount of stuff through a small hole. I suppose you might be able to blow it back out again, - if you got a major backfire, -- but of course this could also blow gaskets out on other cylinders.

After the sealer has dried, check to make sure all the manifold bolts are properly tightened. If you had loose bolts, this will compress the sealer a little, and make it even harder for it to leak again!

Another thing that could happen is that you could have a vacuum hose off (near that cylinder) which is bleeding air in to mess up mixture, (you should also be able to hear this one if engine quiet enough!

Answer 3

check mass air flow sensor and cold air charge sensor