Couple Questions!

**Bedwards** · 03-08-2010

I finally completed my SS M90 install, as I recieved my Intense PCM this morning. I just have a few questions.

1. I'm getting a little bit of a rough idle (not misfiring though). I have read this is a common problem with the SS M90 kit. Does anyone have any ideas on fixing it?

2. After changing PCM's, my fuel gauge is constantly reading empty. Why would that be?

3. I am getting quite a bit of knock at WOT (highest I saw was 9*). I have a Powerlog, 2.5" downpipe, SLP cat-back, cold air intake and 180* thermostat. Would headers make a HUGE difference? Should that be the first thing I do? Should I see if I can get a shop to lower my timing as well?

I'm new to the supercharger, please help me out! Thanks guys!

**Bio248** · 03-08-2010

9* of knock is a lot, id stay out of boost or get someone to lower your timing like 3-4* at WOT. headers will make a big difference. your bottleneck right now is that 2.5" downpipe that wasnt even a good choice for an n/a setup.

**Bedwards** · 03-08-2010

Originally Posted by Bio248

9* of knock is a lot, id stay out of boost or get someone to lower your timing like 3-4* at WOT. headers will make a big difference. your bottleneck right now is that 2.5" downpipe that wasnt even a good choice for an n/a setup.

Hmmm. I'm gonna try find someone who could lower my timing. I wish I had HP Tuners. Gahhh! I know the 2.5" downpipe was stupid.

Any advice on the other 2 questions?

**Bedwards** · 03-08-2010

Bump. Sorry.

**Bio248** · 03-09-2010

question 1: measure your LTFT, what do they read?

question 2: no clue, never seen that happen before.

**matt5112** · 03-09-2010

SSAC's as soon as you can afford them and until then, take the belt off the blower or lay off the boost.

**Bedwards** · 03-12-2010

Originally Posted by Bio248

question 1: measure your LTFT, what do they read?

question 2: no clue, never seen that happen before.

Meaure LTFT at idle? Cruise? WOT?

**Bio248** · 03-13-2010

all of them.

**Bedwards** · 03-13-2010

Originally Posted by Bio248

all of them.

I'll record it on my way to work today.

**Bedwards** · 03-15-2010

Here's my average LTFT's today:

Idle: Range from 0 to 6.2
Cruise at 80 km/hr: Range from 0 to -5.4
WOT: Initially about -10, but adjusts to 0 in a few seconds

I added some octane booster to see if it would help my knock. I just don't understand why it can be so inconsistent. It's usually just when I'm accelerating as well. For example, if I accelerate hard from 30 km/hr, I may see 4* of knock, but if I keep pushing it WOT, the knock will disappear. Other times, I'll see 0 or 0.5 knock when accelerating.

**Bedwards** · 03-15-2010

Could the spark plug gap affect this knock?

**Bio248** · 03-15-2010

okay, the LTFTs look good. i was just making sure they were in line. plug gap wouldnt cause that. too big of a gap would cause misfires since the spark would get blown out. to little of a gap wouldnt do anything.

is it only when youre getting into throttle and then goes away once WOT?

**Spartan GL** · 03-15-2010

Originally Posted by Bedwards

Could the spark plug gap affect this knock?

...

**Bedwards** · 03-15-2010

Originally Posted by Bio248

okay, the LTFTs look good. i was just making sure they were in line. plug gap wouldnt cause that. too big of a gap would cause misfires since the spark would get blown out. to little of a gap wouldnt do anything.

is it only when youre getting into throttle and then goes away once WOT?

It seems like the most KR occurs when I'm in third, and it downshifts to second (opening the throttle). Once I'm past that point, I basically get no KR. I'm unsure if I've seen any KR in first or fourth, now that I think about it. I'm not seeing the crazy high numbers anymore (past 5-6*). I think that was due to having had some leftover 87 octane fuel in the tank.

**Bedwards** · 03-15-2010

Nevermind. I get knock in fourth if I lay off the throttle, then hit it. The only way I don't see knock is if I go WOT from a stop in first. Wtf.

**silverstreak** · 03-15-2010

Your tune is way off. By the time you have someone tune it properly its going to be a pile of pistons. I would highly suggest you drive it like grandma until its dialed in.

**Bedwards** · 03-15-2010

Originally Posted by silverstreak

Your tune is way off. By the time you have someone tune it properly its going to be a pile of pistons. I would highly suggest you drive it like grandma until its dialed in.

I'm going to. I'm getting a new tune from 03impala9c1, hopefully it solves it. I have no one nearby with a tuner, and I have zero clue how to tune myself. This sucks.