3800 Misfires...no SES

[m_dogg]

Well, since I got the Interceptor scan gauge, I noticed that Im having misfires in ALL cylinedrs (only when the car comes to a stop or moves slowly) However, wouldnt the SES light go off with P0300 random misfire code? I changed the wires, installed new coil packs last saturday, and my Autolites 104 are maybe 8 or 9 months old. What in the hell could be wrong here? Are the plugs to blame? I heard Autolites have very short life span.

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[CoolGTX]

got a cam?

I had 104 a/l's in my car for 1 1/2 years, and when I pulled them to change them, they looked good still. a few gaps were off, but I wouldnt have a problem putting them back in regapped(I wouldnt reuse them, because they are so cheap to replace). I run my car on the lean side, so my plugs never get black/fouled, just a slight/slight tan, but mostly white.

your scan gauge will Not tell you individual misfires. my autotap scanner will though.

 

[m_dogg]

<div class='quotetop'>QUOTE (CoolGTX @ Feb 27 2008, 01:02 AM) <{POST_SNAPBACK}></div>

got a cam?

your scan gauge will Not tell you individual misfires. my autotap scanner will though.[/b]

Well I have no cam...yet

As for the gauge, it does show every single cylinder. Its just like driving with a laptop hooked up, shows pretty much everyting you would get from a scanner/tuner. Gotta love those Aeroforce gauges.

 

[CoolGTX]

I run an aeroforce scan gauge daily, and cannot scan misfires with mine.
It was the first batch made.
primitive> :lol:

Ive got a splitter, so I can run both the aeroforce and autotap at the same time

 

[m_dogg]

So...any ideas on the topic?

 

[garrett]

for as cheap as AL's can be had, you might as well go get another set and switch them out. regap them before you put them in. I have a misfire in cylinder 4 right now at idle. Ive changed Coil packs, wires, and next is my plugs. i just put the plugs in there in Nov.
Also, i would check for a vaccum leak somewhere if the plugs dont fix it.

 

[m_dogg]

Im really getting pissed. Just changed the plugs and no results...Im gonna go balistic here :angry:

 

[garrett]

did you check for a vaccum leak. not sure on this, but i believe you just take carb cleaner and spray around the gaskets and check to see if you get any signs. ive never done this before so im not 100% on this, or what exactly the engine will do. if it will want to die or if it will rev but if you have a vaccum leak and spray it im sure it will do something. not a 100% positive on the carb cleaner either. maybe someone else will chime in.

 

[garrett]

just searched clubgp and found this. http://www.clubgp.com/newforum/tm.asp?m=41...&s=#4141350

start spraying carb cleaner at all the sealing surfaces, when the car bogs down or dies, you have found your vac leak.

Thats straight from one of the posts. hope it helps ya out.

 

[Z28_DAD]

what is your EGR% position? it should be at 0% at the times the misses are occuring. if its above 0%, pull the egr and clean it out. get a new gasket from napa with the screen in it. they are the only ones i know of that carry this gasket. you could have carbon built up in the EGR causing it to hang open and causing randon misses.

 

[DaytonaGTP25]

Huh, so misses can be more than plugs... weak, I got bad miss fires and was just going to do plugs and wires... Might as well do the egr also.

 

[m_dogg]

Ill switch back to Autolites 605 tonite. As far as I remember, it did not happen with the 605s, does not hurt to experiment ;D

 

[Sinister Drag Designs]

<div class='quotetop'>QUOTE (m_dogg @ Mar 4 2008, 07:12 PM) <{POST_SNAPBACK}></div>

Ill switch back to Autolites 605 tonite. As far as I remember, it did not happen with the 605s, does not hurt to experiment ;D[/b]

NGK tr-6s > AL 104s

what mods do you have? What gap are you putting these at?
having a plug that is too cold for your setup will cause them to foul prematurely. if your knock free then a set of 605s might do the trick.

 

[m_dogg]

<div class='quotetop'>QUOTE (SINr247 @ Mar 4 2008, 08:25 PM) <{POST_SNAPBACK}></div>

<div class='quotetop'>QUOTE (m_dogg @ Mar 4 2008, 07:12 PM) <{POST_SNAPBACK}>

Ill switch back to Autolites 605 tonite. As far as I remember, it did not happen with the 605s, does not hurt to experiment ;D[/b]

NGK tr-6s > AL 104s

what mods do you have? What gap are you putting these at?
having a plug that is too cold for your setup will cause them to foul prematurely. if your knock free then a set of 605s might do the trick.
[/b][/quote]

3.4 pulley with supporting mods. I still see up to 3* of KR...I gap em @.055

So I switched to 605s and the misfires are still there, not as much but there and for a shorter period of time...I give up...as long as the car runs good and theres no SES light Im satisfied...unless that may cause problems after a while?