Question about ACT location

[99FiveOh]

I've been having some issues lately. One is a problem with bucking/jerking when I let of the gas pedal. Second, I get pinging at WOT which is really BAD with boost. Lastly, I've been noticing it's hard to get it started, like I'll go to turn the key, it'll try to start but then just die. Then, I'll have to turn it over a few times and give it gas to get it started back up, kinda like a flooded carb. car.

I posted up about the jerking problem and I said it started after the 42lb injectors/MAF swap, but there was another mod I made and I feel it's the culprit to all the problems above. I moved my ACT to the #5 runner in the lower intake. I had my car tuned but I'm thinking he didn't make the necessary adjustments for the ACT being moved. My car NEVER pinged before I moved it, it started right up without hesitation and it never bucked when I let off the pedal. I know 42lb injectors won't cause this. So it's between the MAF and ACT.

Can I move my ACT back to the inlet of the S/C and not harm the tune? Or should I just go ahead and tap the discharge tube and run it in there? This is pissing me off cause I spend the money to get it tuned and it's not right!

 

[BlackVert]

so wait ... he tuned it with the act in the intake tubing, not the #5 runner? if so, why not just move it back where it was originally?

or, as i'm sure you already know, most good tuners will make minor mods to their tunes for you if you call them and tell them about your issue. have you talked to him yet?

 

[99FiveOh]

no, he tuned it with the ACT where it is now.

I've called and he said bring the car back in, but I didn't realize that this was the problem till today. I just want to know what moving it back would do to the tune. It seems like he didn't compensate for it being mounted in the intake so moving it back wouldn't do anything bad. The A/F was right on the money though so I don't know.

 

[BlackVert]

if anything, i would think it would make the pinging worse, not better. the act in the runner like that usually results in higher air temp readings than when it is before the throttle body, so the computer wouldn't pull as much timing if you move it back to its original location.

to me, it sounds more like unmetered air is getting in somewhere, but with a blower at WOT, one would think a leak would result in metered air coming out through the leak, not unmetered air getting in ...

is the pinging right after mashing the gas, but before the boost builds?

 

[final5-0]

I know for me to bring up the search word is not gonna be popular
however ...........
I'm positively sure Don covered this very topic and gave some great details
which would help you in your quest for a valid answer.

If you are still running CBAZA and moved the act to the intake
then you are now seeing temps WAY hotter than before.

It seems to me it would depend upon how he did the tune

anyway ... Good Luck and let us know what you find

Grady

 

[99FiveOh]

what the heck is CBAZA?

 

[final5-0]

what the heck is CBAZA?

Sorry

I should have said it like this

If you're still running your original pcm

Grady

 

[99FiveOh]

Yes, still original. Got a SCT chip in it. I just got off the phone with the shop that tuned it and he needs the car to fix the problems. He told me to definately move the ACT to the discharge tube and that will fix 90% of my problems. Then he needs the car to fix something like "fuel on start" or something. We didn't experiment enough with the car after he tuned it to know it was gonna do that. He said no problem to fix so I'll see what he can do.

 

[final5-0]

The info you got from the tuner says it all.

The pcm is expecting much cooler temps than is now being sent
with the act in the intake.

On a similar note about act relocation issues

When you see peeps do the Fox pcm retro-fit thing

You get the opposite kinda thing

You then got a pcm that is expecting much hotter act temps than it
is gonna be actually getting with the act in the intake air stream.

Grady