engine misses

[jwmoses31]

i had three wires go bad and break off of the connector to the spark plug i replaced them but my engines running really rough at idol what can i do?
i have a chevy 350 v8

 

[Jims86]

i had three wires go bad and break off of the connector to the spark plug i replaced them but my engines running really rough at idol what can i do?
i have a chevy 350 v8

Assuming your timing is set at 4*
Pull the plugs out and clean them, then start the engine, And check for vac leaks with some carb cleaner.

 

[chengny]

i replaced them

When you say you replaced them; I hope that you don't mean you only replaced the three that broke off!

If a set of plug wires is in such bad shape that even one wire actually breaks off (or even develops a crack) - dude, it's time to open the old wallet and buy a complete new set. If three wires completely broke off, the rest of the set is surely in poor condition.


The best way I've found to identify bad wires is like this:

Wait till night and get to to nice dark spot. With the engine warm and idling (hood shut to help keep the engine compartment dark) crawl under the engine from each side.

Look up in the area of the exhaust manifolds.

Broken insulation will show up as bright arcing and will be very obvious. Your engine compartment will probably look lke the 4th of July.

 

[Jims86]

No joke. its best not to try to look directly at the plugs to see arcing, look to the side of them....your eys are using the rods instead of cones, which work better as peripheral vision, which is more light sensitive.

 

[jwmoses31]

I replaced all at the same time its running a little better but still rough hopefully new spark plugs should help i was told my carburetor might be defective so i dont know what to do

 

[Jims86]

I replaced all at the same time its running a little better but still rough hopefully new spark plugs should help i was told my carburetor might be defective so i dont know what to do

You should do a compression check before you spend any more money...just to rule out a bad cylinder or two.
Also, have you ever done the intake gaskets? There could be a vacuum leak into the lifter valley from the bottom of the gaskets.

 

[chengny]

No joke. its best not to try to look directly at the plugs to see arcing, look to the side of them....your eys are using the rods instead of cones, which work better as peripheral vision, which is more light sensitive.

I learned that when I first started going to sea. Even engineering cadets had to stand deck watches the first year.

While on lookout at night I soon realized that tiny distant lights from other ships were first noticable in one's peripheral vision.

You couldn't see them when looking straight at them - even when you knew they were there.

I always thought it had something to do with my glasses.

 

[89Suburban]

I replaced all at the same time its running a little better but still rough hopefully new spark plugs should help i was told my carburetor might be defective so i dont know what to do

Sad faces get me all the time.