Weird bogging down issue
Weird bogging down issue Two weeks ago I replaced my spark plugs and wires for the ngk tr 55's and msd wires, shortly there after I noticed my car would bog down in certain rpms under load. I rechecked the connection and everything was snug and correct. I did regular maintenance like changed the oil, new filter, changed air filter, changed fuel filter and I noticed one coil that had a small amount of rust on it so I replaced that as well. The bogging went away in the lower three gears, but under 25-50% throttle it would bog down slightly, well after being parked for two days I drove it today and not only is it bogging between 25-50% throttle, it is also occasionally misfiring, even though no check engine light is coming on. I have no idea what else to check for, I don't know if it's coincidence or not but the issue started right after we switched out the spark plugs and wires. Any advice is greatly appreciated, thanks in advance
Edson
Car is a 99 z28 6speed 85000 on it.
Edson
Car is a 99 z28 6speed 85000 on it.
Last edited by dorifto83; Oct 1, 2008 at 02:06 PM.
Two weeks ago I replaced my spark plugs and wires for the ngk tr 55's and msd wires, shortly there after I noticed my car would bog down in certain rpms under load. I rechecked the connection and everything was snug and correct. I did regular maintenance like changed the oil, new filter, changed air filter, changed fuel filter and I noticed one coil that had a small amount of rust on it so I replaced that as well. The bogging went away in the lower three gears, but under 25-50% throttle it would bog down slightly, well after being parked for two days I drove it today and not only is it bogging between 25-50% throttle, it is also occasionally misfiring, even though no check engine light is coming on. I have no idea what else to check for, I don't know if it's coincidence or not but the issue started right after we switched out the spark plugs and wires. Any advice is greatly appreciated, thanks in advance
Edson
Car is a 99 z28 6speed 85000 on it.
Edson
Car is a 99 z28 6speed 85000 on it.
Also, try putting the factory spark plug wires back on. Its impossible to beat the factory wires unless you're talking about engines making 600+ RWHP. Wires are a waste of money until you start building a mean *** engine. They will offer you ZERO in performance gains for a stock engine.
TECH Regular
Joined: Dec 2005
Posts: 437
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From: Indianapolis
Recheck your plugs and wires. It could be a cracked plug you got in there causing irregular misfires. Your car will not throw codes if it is not a constant misfire, the pcm looks for so many counts before it goes off. I'd pull the wires off and pull the plugs out and take a look at them. I had the same problem and switched out the wires and everything else until I pulled the plugs out and noticed number 7 had two nice cracks in them 
. I'd pull them out and eliminate them from the list since it's free to do and once you changed them the problem started. If that isn't it you may want to be checking into your O2 sensors and cleaning your intake sensors. Oh and about the wires, lay off a little, not everyone buys them for "performance gains" I got MSD's bc they were a hell of a deal with plugs and my stockers were beyond their years and cooked by the headers. He never said he was looking for performance and it has nothing to do with his problem.
. I'd pull them out and eliminate them from the list since it's free to do and once you changed them the problem started. If that isn't it you may want to be checking into your O2 sensors and cleaning your intake sensors. Oh and about the wires, lay off a little, not everyone buys them for "performance gains" I got MSD's bc they were a hell of a deal with plugs and my stockers were beyond their years and cooked by the headers. He never said he was looking for performance and it has nothing to do with his problem. Oh and about the wires, lay off a little, not everyone buys them for "performance gains" I got MSD's bc they were a hell of a deal with plugs and my stockers were beyond their years and cooked by the headers. He never said he was looking for performance and it has nothing to do with his problem.
Since his problem started right after new plugs and wires went on, he really needs to put the other wires back on to rule them out, you never know what you're getting with aftermarket stuff, like my crap wires I got from Taylor. As far as performance, he won't see any gains, but to buy aftermarket wires for a stock or even a nicely built N/A engine, is a complete waste of money. Unless you want them so the engine bay looks better.
I bought the wires and plugs from 99BlancoSS from here since it was $5 more than the autozone price, they came pregapped already. The reason I decided to do all my maintenance stuff is I was getting really shitty gas mileage and figured I'd try to fix it. By shitty gas mileage I'm talking between 150 to 190 miles to the tank. Now I don't have the wires anymore because they got tossed out that day we swapped it, so short of buying new wires, any way to check if the current ones to see if they are defective. I'll check it tomorrow and will let you guys know what I find.
I bought the wires and plugs from 99BlancoSS from here since it was $5 more than the autozone price, they came pregapped already. The reason I decided to do all my maintenance stuff is I was getting really shitty gas mileage and figured I'd try to fix it. By shitty gas mileage I'm talking between 150 to 190 miles to the tank. Now I don't have the wires anymore because they got tossed out that day we swapped it, so short of buying new wires, any way to check if the current ones to see if they are defective. I'll check it tomorrow and will let you guys know what I find.
How do you know the gaps are what your engine needs?
Did one spark plug get dropped and crush the electrode? You need to check the gap of each plug the minute before you put them in to make sure they are correct. Just a thoughtm because losing power at certain parts of the powerband is a symptom of improper gapped plug(s). It only takes one.
