[00silvergt]

Ok here is the quick story. Over the winter I installed bbk longtubes. Today was the first day that I was able to get it out. I took it for a short 6 mile drive. It ran great with no problems. Brought it home and changed the oil and put in a 180 thermostat. Started it back up to check for leaks. It idled fine for about 3 mins and then all of sudden shut off. I restarted it and now it doesnt want to idle right. It will idle ok till i rev it up, then when the rpms drop back down it either stalls or almost stalls. If it doesnt stall then the rpms will go up to about 2 grand and then it drops till it almost stalls again. Repeats that about 4 times then it will idle ok till i rev it again. Has anybody else had a problem like this?

[the real shocker]

about 3 months after putting my long tubes on, my car started running like shit. it idled like i had a large set of cams in it, and if i held it at 1200-1500 in any gear, it would start bucking and cutting out really bad. replaced new maf, new camshaft position sensor, new plugs... pretty much everything i knew that could cause it, and it still didnt fix it.

took it to my tuner, and he ran it on the dyno for a bit and datalogged it when it started cutting out, and ended up being my long tubes causing it. When you install long tubes, you extend the O2 sensors so far down, that at lower rpms the exhaust was actually cooling off before it allowed the sensors to get a good read, and was the computer was trying to compensate for the weird readings it got. He tuned it and fixed all of it

i only know of a handful of other people this has happened to... so it may help or it may not

[00silvergt]

I have a tune coming from Joe at Tricktuners. I will put that on and see what happens. He wants me to send him a datalog anyways, so maybe that will fix it. If that is what my problem is. Longtubes, 180 thermostat, pvc oil separater, and an oil change are the only recent things i have done to it.

[the real shocker]

i dont think the thermostat or pcv separater would cause any problems, but i could very well be wrong! let me know when you find out

[00silvergt]

Yeah I dont think it would be from any of that either. Thanks, I will let you know. Maybe someone else will have an idea until then. Only other thing I could think of would be the IAC valve, but it just seems coicidental that it just now started doing it, after the longtubes.

[Ugmul]

Originally Posted by the real shocker When you install long tubes, you extend the O2 sensors so far down, that at lower rpms the exhaust was actually cooling off before it allowed the sensors to get a good read, and was the computer was trying to compensate for the weird readings it got. He tuned it and fixed all of it

I have heard this from other people as well, No reason a thermostat or actual headers would cause you to stall like that. My bet its your tune/computer trying to adjust for your new headers.

[00silvergt]

I am hoping my new tune will fix it.

[M0T0PSYC0]

hey, did you ever figure that problem out, cuz mine is doing the exact same thing except one difference is that I dont have longtube headers, but do have an o/r h with mil eliminators, no light comes on at all, but there is a very slight exhaust leakat the h-pipe/manifold connection. Pm me and let me know if it turned out to be something other than it needind a tune

[00silvergt]

Once the computer "re learned" the headers, everything was fine. After about 2 starts and shutoffs it ran good.