DriveATransAm

i have a comp cam 224 cam with a 112 lsa. heads are milled 0.050. started the car and she started up no problem. of course i had to give it gas though. kept the rps at about 3K to get the cam all good and lubed. was going great till it got warmed up a bit, maybe 15-30 seconds. then it started to stumble so ide give it more gas and it wouldnt raise the rpms. i dropped them to 1K and it stumbled there for a bit, then all of a sudden shot back up and acted normal. it wont stay at idle though.

i have MTI tuning, and they were supposed to tune it for a cam (when i had the stock one)- they said the program would work with a stock cam too though. the idle is raised too, for the torque converter mostly.

i am running open headers, if that makes any difference. maybe the o2s arent getting a good reading?

i couldnt bust out the autotap since it got kinda late and i didnt need to **** off the neighbors.

anyone have any clue as to what it would be? almost sounds like its running too rich.

this process repeats everytime i start it. wont stay running <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

Tin Indian

Is your car an A4?

If so, that 224 combined with a 112 LSA can give poor idle.

If you find nothing wrong with the install to include wiring problems, I suppose the PCM will need to go back for additional programming.

A couple of years ago, the B1 and its 114 LSA was as big as anyone would go especially on an A4 car.

It seems that now, the "Bigger the Better" bug has infected so many. And with it, many more posts about poor idle, raw gas smelling exhaust, and poor heavy traffic driveability.

You may not have an A4 car, but I hope you can understand where I am coming from.

I surely hope you can work out your driveability problems.

Sorry I can't be of much help. Check all elec and vacuum connections. After that, I guess the PCM will need work.

Ron,

DriveATransAm

i know you read the part about the raised idle for the torque converter <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

its not poor idle, its NO idle. i was planning on sending my pcm back to mti while i was on vacation in a couple weeks. but is there anything i can do meanwhile?

Elite_Hot_Rod

How long has the cam been installed? The PCM goes thru a learning curve, sometimes it takes several trips for the pcm to learn the new cam, mine did.

Mark

DriveATransAm

its been in the car since a couple nights ago, but today was the first time it was fired up <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> .

what do you mean a couple trips?

what is that sensor for that goes on the driverside (rear) of the manifold? it had a thin black plastic hose from a different sensor off the back of the manifold going to it. someone told me it was part of the AIR stuff so i left it off when i put it back together. ill throw that back on in the morning and see if that does anything.

Mike Hoffpauir

Have you recently switched to a ported throttle body? Too much epoxy over the center most hole will cause poor cold start idle.

Also, what size hole is in the throttle body blade? If its the factory hole you should drill it out larger--just a little at a time--to see if it starts to idle better. In most cases it does <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Good Luck

DriveATransAm

stock tb and hole. i was thinking about drilling the hole, but i didnt want to drill too much.

DriveATransAm

i have an ls6 maf calibrated for an f-body sittin in the garage. maybe that will lean the car out if it is truely running rich.

6-SpeedZ

iTrader: (1)

I would do nothing until you have drilled the TB blade hole out larger. I belive mine is now up to 7/32, and could go bigger yet. Use your A-Tap to get your IAC counts into the mid 30's when fully warm at idle. Atap it every time you drill a hole, and you'll see the IAC counts continue to drop as you make the hole bigger.

Mike Hoffpauir

I think working with the TB hole will get you sorted out. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

RPM WS6

iTrader: (3)

Roy, your TB hole will most likely need to be 13/64 or bigger to work right. FWIW, my TB hole is either 11/64 or 13/64 (can’t remember now) and my 114 cam idles just fine (even with the A/C on) with my IACs in the 63 range. Actually, I plan to drop my idle further once I get Edit next week. I’m at 950/850 right now and it’s too high, IMO. I’m going to try 800/800, or maybe even 750/750. Don’t know why MTI sets the park idle higer than the drive idle??

Anyway, I too noticed that it took a while (at least 150 miles) before my PCM learned the new cam. Even now, it will stall sometimes on warm starts, but that’s pretty rare. Otherwise it runs fine, except I need to mess with the misfire tables so I can get my TC lockup back. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

DriveATransAm

thanks guys. i pulled the pcm fuses and will try drilling it out on my lunch break. ill see if that helps any <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

JimmyKash

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by RPM WS6:
<strong>Don't know why MTI sets the park idle higer than the drive idle??

</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">if you ever notice, EVERY production car does that because in park there is no load on the motor and if it was that low, it would stall

DriveATransAm

ok, i plugged that thing back in, and drilled the hole to 7/32. it seems to do fine when i keep the idle at 900, but if i let off the gas it surges pretty low and just cant keep it going.

hmmm.

sounds bad *** <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

BradWS6

iTrader: (3)

Have you done a idle relearn yet..it's going to take some time for the computer to learn.

Pro Stock John

iTrader: (34)

ROY...

What is the IAC count on Autotap?

80-125 is too high.

Really 30-40 is good but I have gotten by with 50-60 too.

I think 125 is maxed out.

Surging means it's too rich at idle.

What are your Ltrims? -20%?

DriveATransAm

im loading the old a-tap back in as we speak.

whats the largest i can make the hole?

Pro Stock John

iTrader: (34)

I have two holes the size of #2 pencils with my cam. But my IAC count is low, like 8-10.

I8COBRA

iTrader: (56)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by DriveATransAm:
<strong>im loading the old a-tap back in as we speak.

whats the largest i can make the hole?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Hey Roy, I got a pick axe you can borrow. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

DriveATransAm

well, its running!

i threw the exhaust on, and i cant even hear it now <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> . i have a cat on the pas. side and off road on the driverside. dont ask <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

i came home from work and hooked up the a-tap. started her up and she fired right up. i figured as long as she was running, ide let it idle. and sure enough, it idled fine! so i threw it into drive and she dipped down for a second but caught herself. i just drove to get gas and nothing broke <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> . oh sweet!

im am giddy like a shcool girl now. ive had a little piece of papertowel under the throttle, so im sure thats helping keep the rpms up. its right about 850 on a-tap.