Detonation?

Davedangerous · Feb 29, 2008, 04:50 PM

While heading home from work this afternoon I experienced a loud boom. At first i thought i dropped the tranny.

It happened when I started to get on the highway in 2nd pulled into 3rd 4th and in 5th is when i heard it. I immediately pushed down the clutch coasted for a few seconds and then threw it into 6th. I'm assuming that its because its pretty cold (19 degrees) and we're expecting some snow. not sure if its detonation...any ideas??

mods are cobb stg 2 93 ver100b
mr dp, mr test pipe, hks cbe

Davedangerous · Mar 1, 2008, 10:04 AM

i did some research and since i encountered fuel cut previously with the original map offered by cobb, it could have happened again. I went for another spirited drive and nothing. I'm thinking that I need to get a protune.

razorlab · Mar 2, 2008, 07:45 PM

Sounds like fuel cut (boost cut)

CPA5 · Mar 3, 2008, 08:52 AM

could the loud boom be attributed to an intercooler coupler coming off? although it doesn't seem so since you've driven it again and all things seem fine

Davedangerous · Mar 3, 2008, 12:53 PM

i originally didn't think that it was fuel cut because it sounded different, atleast i thought it did. as i mentioned before i think the freezing temperarure attributed to it.

razorlab · Mar 3, 2008, 01:31 PM

The colder temp probably caused a boost spike or higher boost (which can be mostly tuned out via the boost tables) and it hit higher load and thus fuel cut.

TheEvolutioner · Mar 5, 2008, 08:59 AM

Definately boost cut, happened to me usually at 5th or 6th gear, @ around 5k rpms. Contact Christian at Cobb and he will hook you up with a revised map to stop to boost cut.

Davedangerous · Mar 6, 2008, 11:51 AM

Quote:

Originally Posted by TheEvolutioner

Definately boost cut, happened to me usually at 5th or 6th gear, @ around 5k rpms. Contact Christian at Cobb and he will hook you up with a revised map to stop to boost cut.

i'm running the revised map, what i need is a protune