I did some searching just now and I wasn't able to find anything that was exactly along the lines of what I had happen tonight, so I am going to post up. Please be gentle if I missed anything...

Anyways, I have a 2006 SS/SC, injen intake, stage 2 (GMPP), GM catback, Zex plugs.

Tonight, I went out to eat. Before I ate, I parked the car at the restaurant. No problems, car is running fine, no rough idles, nothin. Well after dinner, we leave the restaurant, car is running fine in the parking lot... turn out and all is still well. Come up to a stop sign, and the crap starts.

The car starts to idle rough, but nothing to catch my attention other than a "thats odd" I accelerate from the stop. After I get through the intersection, I give it a little bit of gas, all of the sudden, it sounds like a harly just came up to my window and revved up real high. "Holy hell what was that!" I let off the gas and it stops.

Now I notice that the car doesnt have much push, but I can still accelerate lightly. The loud sound comes back if I give it too much gas, and as I drive on it gets to where very little gas will make some form of this noise. It wont be extremely loud though.

I get into a parking lot, and stop. At this point the check engine light starts flashing. Turn the car off... Take a look in the engine bay and nothing is leaking, no visible signs of suck. So I have my other half start the car while I am looking, and it runs very rough and has some loud popping noises that I know shouldnt be there. Turned it back off.

Used the interceptor to get codes. Its throwing a P0300, random misfires. Awesome...

Anyways, as far as I can tell from my limited research I have a few things it could be. But I am not sure where the loud noises should put me.

Is it a clogged cat? Bad plugs (quite likely )? bad coil? MAF or a hole in my intake somewhere? I think tomorrow I may try and disconnect the battery for a while, and try and start again to see if it will idle at all. Speaking of which, I had the bitch towed home, I didnt want to drive it like that.

The thing that is confusing me so much is that before we went in for dinner is was totally FINE. Nothing seemed wrong. Then we left, and got maybe half a mile away before I pulled over and it sounded totally screwed. Confused as hell here...

Thanks in advance, and sorry for the length
John

 

check plugs, maybe some bad gas.

 

I did just fill up. Am down to 7/8's of a tank now. I wont ever buy shell again if this is the case...

I may see if my local autozone or oriely has some ngk plugs tomorrow morning. Couldnt hurt.

 

I would check the intake. Aluminum likes to get holes rubbed into it. Also check to see if the filter may have fell off. Sounds like the car is going into limp mode.

 

I think I Am going to get into the fender and check on the intake. Damn thing...

 

i see you have zex plugs. they dont have a great reputation for our cars.
My car loves shell 93. always go to the same station. but different stations have different gas and different holding tanks. could have a bunch of water in it or something.

 

I am definitely going to yank the plugs... Get into the fender to check the intake... and if that doesnt fix my problem, and its the gas, what do I do? Run it through real gentle?

And if it was something with the intake getting a hole or filter falling off, wouldnt I get a P0171 (lean) too?

 

Check where the intake goes from the engine bay into the wheel well. It rubs bad in the hole there. It could also be the cat as well. They are known to go as well.

 

The cat would be the most fun... Give me a good excuse to get some headers and a downpipe.

 

I had to replace my injen because it got holes rubbed into it so it wouldnt surprise me if that was the problem. I just ordered a CTI 3" downpipe, im waiting to get their header though.

 

Intake wouldnt cause a random misfire, Id bet money its your plugs

 

ngk bk7re is what I should be lookin for, right? (to replace mine with...)

 

yea those are the one range colder copper plugs

could be a lot of things. you have to start looking somewhere lol.

 

if it is better when u barely giving it gas then when u give it more its fells alot worse means u probably have a spark problem.. get rid of the zex plugs and run the stock autolites. unless u have a stage kit then get colder plugs....but a spark is a spark and the stock autolites are what come in it so stick with that.

 

The random misfire code is a PITA to figure out

 

lol awesome

 

I bet its your plugs, Thats the most common thing to trigger the mis fire code, Theres no way an intake would cause it....

And i really dont think theres anyway a cat could cause it...

 

yes, a hole in the intake will give a lean code because the engine is getting more air than the maf sees.

if its bad gas, go to autozone or wherever and buy some dry gas.

 

Yea a lean code, Not a misfire code

 

Thanks all... I am going to start with the plugs and intake. I might have to let her sit till next weekend though

 

you know, if your running too lean, you'll get misfires, right?

 

Did you try clearing the code?

There's a code I threw on mine one time that didn't show up when I scanned, but it was there. When I would come to an idle, it would idle VERY VERY badly and wouldn't run right until I cleared the DTC's with my interceptor. After clearing, it ran just fine until I stopped at the next red light and idled.

 

I'm hoping this is unrelated, but I just went down to look at the car this morning -- didnt start it though -- and the reservoir for my heat exchanger looked low. If something broke and it was sucking dexcool through, would these symptoms match?

Please say no. That would be very bad. I haven't even done anything to the heat exchanger system...

 

i doubt it. the manifold would have to crack for that to happen, which would cause a whole other set of problems.

to get misfires from being lean, it would have to be so lean its not even funny. also it would be throwing a code for lean fuel trims

 

Good, I hope that is the case, because if that dexcool got in there would be a freakin teardown/rebuild coming and I dont have the cash for that. Although it would be fun

Well neither of my local parts shops have the ngk bk7re's (suprise!) so I gotta order them.