Brendan's 99 Grand Am GT update

[geldartb]

ok well i took it to the track and well it ran like absolute shit. after getting home and talking to a few people and sitting there thinking to myself it appeared that there was a spark issue somewhere.

got some super fast 18.1 and 18.2 slips and once i fixed one thing with the air temp spark it got up to 17.1.

so this week i swapped out the ICM and coil packs. ill test later its took hot to try that right now. but it seems to start and idle better and the best part i can now go WOT without it running like absolute shit.

had it out today and it ran great. went easy on it for the first 30 min or so to give the pcm time to relearn stuff and then did a 0-70 run and it pulled good without any problems.

heres the latest with the changed intake setup. LS2 maf and the same K&N filter i had in the fenderwell. the air filter is attached right on to the maf. i added the IAT that i was running before. i just wanna see if there's a drastic change in IAT temp vs the built in IAT the LS2 maf has.

[IsaacHayes]

Remember the new MAF is going to read differently than the stock one.... It will be scaled differently.

[geldartb]

i got the numbers for the maf on the laptop and it was all set up in the pcm but since the spark was screwed thanks to either a bad ICM or coil it wasnt truly running correctly im gonna start over with the tune in that area.

i had the lower end(ie the idle-cruise part of the maf) of the maf tuned out to where the LTFT were within +/-5% of zero but since the spark wasnt 100%, all of the fuel prob wasnt getting burned the way it should and thus screwing with my readings.

before i even had the LS2 maf at my house i was researching the flow numbers and getting that ready.

a wideband is def next on the list.

[geldartb]

another thing i found today that pissed me off.

well the last few scans and its prob been like this for awhile but i was on my way back to the garage and started up a scan well on the way back i was looking at the iac counts it was pegged at 255 the whole way.

so i get back im sitting out front fire the car and the scanner up again while looking at the scan. whether it was in park or drive the number didnt change from 255.

i get out the tools and pull the iac to check it. i get the last screw out and while im sliding it out i notice the spring is getting kinda long and once its out theres nothing on the end of the pintle. look inside the hole and theres the little metal thing thats suppose to be on the end.

somehow it threaded itself off the pintle. it must have been like this for sometime cause there were a few scrapes on it from being pushed around.

im getting an AC DELCO unit im sick of this cheap shit from autozone.

[SappySE107]

Check my clearance rack on the store. I have a bag of IACs.

[geldartb]

well i screwed the thing back on the pintle just to get it back in the garage. but i somehow managed to collect a bunch of these things along with coil pack and icm's.

ive just never seen the thing come unscrewed from the shaft before. wish i could find the receipt cause id bring the hunk of shit back.

still want to check the coil pack/icm setup that i had on there since they are the ones that came with the motor and prob have 8k miles if im lucky on them.

if i strike out on the iac's i got ill hit you up.

the ones you get from the parts stores look cheaply made compared to the gm counterparts.

maybe ill go do some tinkering with the car tomorrow. its suppose to rain thanks to hurricane danny so im guessing no outside ish.

[SappySE107]

It have only seen that happen on an IAC reset with the valve out of the throttle body. It looks like the computer was commanding it though but if it was blocking the IAC passage, it would have to keep trying. On OBD1, I can set the max IAC steps.

[geldartb]

yeah ive done that by mistake once. had the iac sitting on the plenum turned the key on forgetting it was sitting there and pop goes the pintle.

never had any drive-ability problems. its been a few days since i replaced the coilpack setup and since then its ran fine.

maybe the vibrations from the solid mounts did it or just a shitty one from where ever the hell these things are made. im gonna swap it out though.

lucky you guys didnt make the hole any bigger or that would have gotten sucked in my engine. it was kinda half blocking the hole when i looked in.

it was definitely commanding the iac. the count was pegged at 255.

i think from now on im done with aftermarket parts. shitty bosch o2 sensors and now this.

[SappySE107]

You can't be serious about solid mounts causing that thing to fail.

[geldartb]

oh no im not serious about that. the iac was most likely botched from day one.
ive had weirder things happen but this is kinda at the top of the list now.

if i can find the receipt its going back although i think that might be one of the things they ask your phone number for so it should be in there computer and the site says it has a 2yr warranty so back to the store this hunk of shit goes.

[pocket-rocket]

Yeah, Autozone keeps your info in the computer. You should be OK without a receipt. That's about the only thing they do right there (besides accept returns, lol). I had a manager there tell me the other day while I was getting a battery checked (not for my car) "You're one of the lucky ones today" referring to the fact that this battery was ok and not a bad one...

[geldartb]

ill be going back on sunday with the part exactly how i took it out of the throttle body. i still have the original box it came in.
i honestly hope they give me a refund i really dont wanna put another one of those things in my car.

i think ill bring the icm and coils to see if they can test them.

im just lucky the hole in the tb isnt huge or else that would have gotten sucked into my engine.

[IsaacHayes]

Autozone parts FTL. I've had a CPS go bad in a few months there... Same for other stuff I've heard from others. I only get NAMEBRAND parts there. They are the only ones that carried TIMKEN bearings... If it's a name I know, I'll get it, but electronic parts there nope.

My Denso O2 from sparkplugs.com has done me well. No bosch for me.

[geldartb]

i only did the bosch o2 cause i was in a hurry that time but thats getting replaced over the winter with a denso one and ill be ordering a iac from GM too if the ones i got are duds.

[underdawg]

I love the 'stealth' look of your car. If I ever get another Z it will get the 'stealth' treatment as well as some performance goodies.