Ok.... car surging and dying again......

[PQ]

Originally Posted by Higgs Boson

right. more means base running airflow or also called idle air. basically how much the tb opens to maintain idle with no driver input.

if the idle is bouncing then your idle spark is wrong or your running airflow is wrong or both. the idle corrections are trying to get it back to idle target rpm but can't keep it there.

yes it can seem worse sometimes than other times.

it only happens under certain circumstances because lots of things affect your fueling and spark like ect, iat, etc etc.
if it dies coming from a roll or the dropping rpms don't catch idle then there are a few other criteria to address as well.

Doesn't really die coming from a roll.

So maybe I just need it tuned?

Here is a video that I took while trying to get the car to do the surge.

Now it never did it in this particular video but just as I start the car (and I know it can be normal) but the way it starts, goes low, and then recovers is what it does in idle backing up but even worse.

Again, just as an example. I'm not saying it's not normal as I start the car.

I actually got it to do it later but accidentally deleted it.

Everything after about 15 seconds is a waste of time.

[Higgs Boson]

my money is on idle airflow and or idle spark timing.

it can take a lot of tweaking to get it just right so don't be mad at your tuner. ;-)

[PQ]

Originally Posted by Higgs Boson

my money is on idle airflow and or idle spark timing.

it can take a lot of tweaking to get it just right so don't be mad at your tuner. ;-)

Not mad. But they are 4 hours away.


How bout this. Like I said, my EVAP hose was pinched between the vent solenoid and the EVAP canister. As I go through things to check, I wonder if this has any merit?

• A malfunctioning vent solenoid (EVAP) will emit unusually high emissions during testing. This is because gasoline fumes are not being sent through the vent solenoid. This build-up of fumes inside the fuel lines can also cause the vehicle to misfire or stall.
• Another sign of a malfunctioning vent solenoid is when the vehicle's engine coughs or chokes during ignition. This ignition problem is caused by enough fuel entering the fuel lines. Gasoline fumes are typically stored and recycled in the EVAP canister. The vent solenoid then acts to prevent liquid fuel from entering the EVAP canister. A malfunctioning vent solenoid will allow liquid fuel into the EVAP canister, preventing a smooth flow of fuel into the engine during ignition.

[1sikRS]

Originally Posted by PQ

Full tank, low tank, never matters. It's done it both ways as far as I remember.

And don't scare me like that.

Car runs great when given gas. Even when held to the right RPM.

I'll try and keep notice though just in case.

If the fuel pump does crap out a zl1 pump will perform much better in our cars so I've read

[mlee]

Get rid of that Pipeline CAI...

[Matster]

Hey PQ, most likely in the tune. You mention that it does it when it is Hot outside but not when the outdoor temps are cool. I'm no expert by any stretch of the imagination, but in hotter temperatures the car will pull timing in order to keep AIT down to prevent pre-detonation. Now I'm not sure where it get AIT from, MAF sensor? Like I said, I'm no expert I leave that to my shop.

It took 3 days on the dyno last summer to get mine dialed in with temperatures in the shop of over 100F and humidity that was way up there. After one pull on the dyno it was pulling timing so much that it had to sit for 30 - 45 mins before they could run it again.

[Supercharged SS]

Originally Posted by PQ

No. It's the same CAI that was on it before and when it went to Vengeance. Nothing has changed.

Seems that Vengeance may have just masked an already there issue? Not intentionally of course but it wasn't doing this when it left them. Wasn't idling perfectly smoothly on the tach but I attributed that to the cam.

Breather. As is a valve cover breathe. Not a cai.

[Scott@Bjorn3D]

Could take MAF out and clean it. Since the car ran fine last summer after the tune. Also double check it the MAF while out cleaning it that it is a double digit strong one. A weak one being dirty would be real bad versus a strong one being dirty.

[Dr Jkel]

Randy...I have had the same issue with the kinked hose and replaced it...Don't know really what it did but it seemed to help.

Since I have been helping work on the tune for Mr. Hyde I have actually learned just a few things that COULD be causing your problem.

These things dramatically have to do with idle and surging first would be the IATS( Idle Air Temperature Sensor) IAC ( Idle Air Control) and the TPS ( Throttle Position Sensor). I am not even sure our cars have them put from my understanding all fuel injection does. I don't even know how to check these sensors.

I know Matt played with the tune while Hyde is running and it drastically changes how it idles.

Since your issue has been there for a good bit of time and it seems affected by temperature change I would check these...I could be out in left field just a thought though.

[BLACK10]

Originally Posted by Higgs Boson

my money is on idle airflow and or idle spark timing.

X2

your car was probably tuned in cooler weather. now it needs to be tweaked since its really hot out side.

[SC2150]

A failing MAF may cause all you describe and it may not throw a CEL....not sure if that has been swapped out (did not read all the posts in the thread).

[GTAHVIT]

Originally Posted by Supercharged SS

Breather. As is a valve cover breathe. Not a cai.

LOL he knew what you meant. I think what he was trying to say is that nothing is different on the car. The breather, catch can MAF CAI... nothing has changed since it was tuned.

Originally Posted by BLACK10

X2

your car was probably tuned in cooler weather. now it needs to be tweaked since its really hot out side.

We didn't have time for a cold start or an idle tune when we originally tuned it after the blower... here in Jax. after that, vengeance tuned it at the Fbody Gathering. Still had the same problem. Then it went back to vengeance for a cam and retune. Problem went away. and now is back.

Originally Posted by SC2150

A failing MAF may cause all you describe and it may not throw a CEL....not sure if that has been swapped out (did not read all the posts in the thread).

This makes sense.... Randy, have you cleaned your airfilter recently???? or ever???

Originally Posted by mlee

Get rid of that Pipeline CAI...

Mike, Why don't you like the Pipeline CAI

[Mr Twisty]

First thing I would try is forged bottom end.....

Hey, it worked before with your exhaust leak, didn't you get a cam out of that deal?

[Pro Stock John]

OP has what...

full exhaust
cam
blower
cai
...and is 6 speed?

MAF: If you don't have time to bring it anywhere, buy another MAF and try it. If the MAF filaments got dirty or damaged, could be a cause.

IAC: I don't know how these work on the 5th gen, on the 4th gen it was in the side of the TB and it could be removed. If the IAC counts were goofy on a 4th gen the idle would surge all the time and not calm down, and the cars would die when coming to sudden stop. As I recall the MAX IAC correction was 25 (anyone else remember).

TPS: Senses the throttle position. with DBW not sure it works on these cars.

Going up a hill sometimes dies? Just turns off or chugs or what?

Before you go nuts changing stuff and buying stuff, Do some poking around. Look for burned wires around the exhaust. On the 4th gens the crank position wire ran down the passenger side by the headers, and if it burned the car would run weird. Call Ron @ Vengeance too, he's a good smart guy.

Maybe you can find someone local to scan the car for you.