valves timming need help

[partyplace69]

i have done some reading and i was wondering if anyone can help me. my car is running but really crappy. it has a bad mis. what to look for? if its a valve or timming

 

[madmader]

i have done some reading and i was wondering if anyone can help me. my car is running but really crappy. it has a bad mis. what to look for? if its a valve or timming

You can trouble shoot more then a few things that would cause a missfire. Can start be eliminating one at a time.

What the condition of your timing belt? Did it slip a tooth some place?

Spark plugs not fouled? Gaped right?

Spark plug wires not nicked, or gaining extra resistance them spec.

How about your coil packs or igniter?


thats stuff can point you in a direction of "where to next"

 

[SinaiTSi]

When I first got my car it had a bad miss. I did all of the simple stuff and nothing fixed that nonsense so I took it into a shop. They figured out that I had a burnt intake valve, I'm not really sure why or how. If you're timing is off, I'm pretty sure that you would just be knocking your valves against your pistons. So, once you do all of the simple stuff, like plugs, wires, stuff like that, then take the head off yourself and examine it or take it to a shop. My money would be on one of the valves.

 

[madmader]

So, once you do all of the simple stuff, like plugs, wires, stuff like that, then take the head off yourself and examine it or take it to a shop. My money would be on one of the valves.

Yes it could be a valve, could be a lifter, could be a rocker. Do the simple things first. You can do a compresion check later.
Then you can keep going and do a leak down test. You can actually point out the problem without tearing off the head to look.

 

[Spyderman7]

Check plugs and wires, then do a compression test.

 

[partyplace69]

the compression is 140ish for all and valves are good no bent ones i am going to change my plugs and wires and maybe coil pack. what else can i do

 

[Spyderman7]

The compression is fine.You can pull the plug wires off one at a time while the engine is running.See which ones don't make a difference in how the engine runs when it is unplugged.If you just have one bad cylinder,it's probably just a bad plug or wire.If you have two bad,like 1and 4 or 2 and 3 then it could be a bad coil or module.

 

[partyplace69]

i just changed the plugs and wires. it runs like a champ but at idol its has a very little miss. i checked and reset trimming to 5 btdc, but i noticed that it jumps a little 5 to 10 btdc what could that be? i can hit 15 psi all day now its just when it at idol it has a little miss.

 

[madmader]

Your timing should not be jumping, did you make sure you grounded the Computers timing terminal?
No extra electrical/hydraulic loads on engine?
Is it at normal Opprating temp.

VFAQ has a good tech help.
http://www.vfaq.com/mods/wayback/BradBauer/engine/timing.html