Alright, had a chance to read the codes that were set from the exhaust today. I had 401, 404 and 299. I know that just about everyone with exhaust gets the 401 and 404 , but i did a search and found a few more that got the 299 as i did. First can anyone who got the 299 chime in here. Did fingersticking take care of it? Is the ECM all confused from the EGR readings that it throws the low boost code too?

I got the check engine light with my exhaust (fed emissions truck) so i'm thinking the 299 is the only one throwing the light.

Also, cleared them off, gonna see how long it takes the the CEL to illuminate again.

I have gotten the p0299 code 3x now, the 401/404 4x and the p1093. The 299/401/404 were set the same time, light take off shift, cough, then code, the p1093 cranked her up on the on ramp and when I let off it showed the code and I had to cross 3 lanes of traffic @ 70 to pull over. The Fingers stick is to night, we'll see, road trip to the Twin cities Friday.

I also get the same codes, but I don't think the 1093 is from being straight piped(I'm running a muffler). The 1093 is not enough fuel, from what I have read. I received an email informing me the Fingerstick is on the way and I'm anxioulsy awaiting its arrival!:ro)

PS- I haven't set off the 1093 in tandem with the other codes....yet!;)

I get the same codes too 299, 401, 404. (not the 1093) I haven't had the balls to start cutting into the harness to do a fingerstick. So far it doesn't happen too often... so I just keep clearing it.

I've noticed that quite a few guys are getting the 299 code along with the egr codes. Has anyone that has blocked the EGR and installed the stick still got these? The low boost code is probably from the loss of boost pressure through the EGR valve when it opens due to the lack of exhaust pressure. The EGR flow is normally created as the exhaust backpressure is greater than boost pressure.With a low backpressure from no cat and larger exhaust, boost pressure may be greater and is "lost" through the EGR valve when it opens, generating a low boost code and engine "hiccup"------just an idea.

So a fingerstick and plate should fix it.

Thats weird I'm running the Banks exhaust down pipe back with no cat and I have never had any codes set yet and I have a 2005 LLY .

Alright, tried some things. First I have noticed that when the check engine light is on for the exhaust, there is some kind of defuel above 2200 RPM (anyone else notice this?). The truck just kinda "dies" in upper RPM ranges. Once the codes are cleared runs great. I figure that the 299 low boost is the only code setting the check engine light. I tried to disconnect the EGR plug and then clear the codes, thinking as long as i dont get the underboost code there wont be defueling. Then after the first start the check engine light came back on (I assume when the EGR failed the first diagnostic check), but there seems to be defuel about 2200 RPM again. Didnt get a chance to see what the codes were this time but I wouldnt think i got the 299 underboost because of the egr being unplugged.


Any thoughts? I ordered my finger stick so that will probably take care of it, but i was looking for a temporary fix for the defuel with the check engine light on.

Well guys,

So far so good!! The codes have not come up(must mean I installed the stick correctly):h ) Finger stick should take care of the codes, except the 1093!;)

Well guys,

So far so good!! The codes have not come up(must mean I installed the stick correctly):h ) Finger stick should take care of the codes, except the 1093!;)So it appears the 299 comes up only with the egr codes. I'm wondering if the 299 is a code that pops up as kind of an engine "limp", kinda like the allison. Meaning that there actually isnt underboost that tripped the light, but that the engine purposly creats less boost when the codes are tripped. Just taking a stab at it, anyone out there agree?

I think this because i got the underboost code when I got a check engine light for the coolant and fuel temp sensors (plugging truck in when it was too warm). I think this code just trips meaning that the engine will be running at a lower boost level, like the VVT purposely dumps boost as a "limp" type mode. What do you think?

I cant imaging that the turbo is actually producing less boost because of the exhaust and egr, because as 05 2500HD said all he did was install the finger stick and took care of the 299 code. I would think that if the EGR actually caused less boost then it wouldnt matter if the finger stick was installed or not (since it doesnt change the EGR's operation). I dont think this is the case though, i think its a "limp".

Just a thought, can anyone back that up.