Need help with IACs and surging after cam install
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From: Barbaria
Need help with IACs and surging after cam install I have a single pattern 218 563 lift cam on a 114 LSA, with an asp crank pulley and a vig 3200. Those are the only things I have that I think would affect the surging.
Right now I have a 7/32 hole in the TB, tps voltage is .48. I can't get the IACs to steady out. Am I supposed to be checking IACs in park, drive, or neutral? So far I've done it in park. The IAC value counts down from 50 to 0, surges and goes back to 50. This cycle repeats every 4 or 5 seconds.
Do I need more air or do I have too much?
Thanks.
Jim
Right now I have a 7/32 hole in the TB, tps voltage is .48. I can't get the IACs to steady out. Am I supposed to be checking IACs in park, drive, or neutral? So far I've done it in park. The IAC value counts down from 50 to 0, surges and goes back to 50. This cycle repeats every 4 or 5 seconds.
Do I need more air or do I have too much?
Thanks.
Jim
Re: Need help with IACs and surging after cam install Surging = too rich.
Here's a simple test. Go over to Bos' car, take off his MAFT, put it on your car, and set the base to -10%, tell me if the surging goes away.
Here's a simple test. Go over to Bos' car, take off his MAFT, put it on your car, and set the base to -10%, tell me if the surging goes away.
Re: Need help with IACs and surging after cam install Same cam here and no surging at all with the stock pcm and a 3/16 TB hole. I only got to drive the car for part of a day though before my tranny blew.
Did you reset the pcm and do an idle relearn?
Did you reset the pcm and do an idle relearn?
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From: Barbaria
Re: Need help with IACs and surging after cam install John, I don't know if Bos will let me take his parts, you know how he's weird like that. I'll have to kick him. Wait...does Bos even need a MAF-T anymore with BV programming?
I popped the screen out of the maf and it runs a little better now. Would adding hpp3 rfg tuning lean it out just a little more?
Reboot, I've done an idle relearn twice now. It's hard to start when it's cold, but after it warms up, the car has never died on me. The surging is liveable, but still very annoying.
I popped the screen out of the maf and it runs a little better now. Would adding hpp3 rfg tuning lean it out just a little more?
Reboot, I've done an idle relearn twice now. It's hard to start when it's cold, but after it warms up, the car has never died on me. The surging is liveable, but still very annoying.
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Re: Need help with IACs and surging after cam install Jim,
I got the same cam from Tom @ ls1speed. The TB hole is probably 13/64 as this is what mine was and still the car would not want to idle, it was surging and would die once in a while. I noted my TPS at idle (as you have) then I raised it via the idle set screw till I liked the idle and surging was gone. Just make sure you don't go over 750rpms at idle. My TPS ended up around .7 volts and it idled around 750 rpms (+/-) 25 rpms. Only got the SES (high idle speed) once. I then turned down the idle set screw a 1/4 turn and never had it since.
I finally decided to get the idle raised and P0300 code deleted my sending PCM to MTI. COst just $250. But I wish I had waited because now I will have BV custom tune the car aand he could have done this as part of the custom tune.
- Tom
PS. got to love the 218 cam and the Vig3200 (see sig)
<small>[ March 15, 2002, 07:33 AM: Message edited by: Tom99SS ]</small>
I got the same cam from Tom @ ls1speed. The TB hole is probably 13/64 as this is what mine was and still the car would not want to idle, it was surging and would die once in a while. I noted my TPS at idle (as you have) then I raised it via the idle set screw till I liked the idle and surging was gone. Just make sure you don't go over 750rpms at idle. My TPS ended up around .7 volts and it idled around 750 rpms (+/-) 25 rpms. Only got the SES (high idle speed) once. I then turned down the idle set screw a 1/4 turn and never had it since.
I finally decided to get the idle raised and P0300 code deleted my sending PCM to MTI. COst just $250. But I wish I had waited because now I will have BV custom tune the car aand he could have done this as part of the custom tune.
- Tom
PS. got to love the 218 cam and the Vig3200 (see sig)
<small>[ March 15, 2002, 07:33 AM: Message edited by: Tom99SS ]</small>
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From: Chi-Town, IL
Re: Need help with IACs and surging after cam install Supposly BV performance is starting to not return phone calls, and thats even to Speed Inc...they won't return Joe's calls either....
I want my car tuned, but I want my phone calls returned as well when something is wrong..
I want my car tuned, but I want my phone calls returned as well when something is wrong..
Re: Need help with IACs and surging after cam install BOS -
I have had the same experience. Called Brian and left messages. Also emailed him to setup the appointment. First couple of emails went great going back and forth to get a date we both could live with, but he has not replied to me last gfew emails in over 2 weeks. I know he is doing some SCCA stuff but now I am on hold.
- Tom
I have had the same experience. Called Brian and left messages. Also emailed him to setup the appointment. First couple of emails went great going back and forth to get a date we both could live with, but he has not replied to me last gfew emails in over 2 weeks. I know he is doing some SCCA stuff but now I am on hold.
- Tom
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From: Chi-Town, IL
Re: Need help with IACs and surging after cam install I understand that he could be busy...but I've been carless for a month and was looking forward to going to the track and because of him not returning phone calls, etc, I won't be able to...
oh well, I should get the car monday or tuesday
oh well, I should get the car monday or tuesday
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From: South Jersey
Re: Need help with IACs and surging after cam install Jim,
I installed a 224/224 114lsa cam and a Vig. 3600 in my car recently. My car surged alot even with custom tuning. What you are looking for is a IAC count to be in the 30 to 40 range when the car is totally warmed up and it's sitting in park. My counts were at 80 before we drilled the TB. You want to drill a little at a time until you creap up on the 30 to 40 count. It seemed to work on my car with a bigger cam and converter. Give it a try. Good Luck.
Den
I installed a 224/224 114lsa cam and a Vig. 3600 in my car recently. My car surged alot even with custom tuning. What you are looking for is a IAC count to be in the 30 to 40 range when the car is totally warmed up and it's sitting in park. My counts were at 80 before we drilled the TB. You want to drill a little at a time until you creap up on the 30 to 40 count. It seemed to work on my car with a bigger cam and converter. Give it a try. Good Luck.
Den
Re: Need help with IACs and surging after cam install Dennis is exactly right.
Warm the car and drill the TB til u see 35 to 45 IAC counts in park.The car should hold a nice steady but choppy depending on the cam idle.
JS
Warm the car and drill the TB til u see 35 to 45 IAC counts in park.The car should hold a nice steady but choppy depending on the cam idle.
JS
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From: Cecil County Raceway!!!
Re: Need help with IACs and surging after cam install hmmm, my IACs are 79-81 and it don't surge...I don't think I'm touching anything <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
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From: Sacramento, CA
Re: Need help with IACs and surging after cam install What about surging when you come a stop, most of the time rather quickly. If I slow down very slowly then it usually is no as bad. Once the car is sitting for a second then the idle is nice steady and holds rock solid at 850 where I have it set with LS1 Edit.
My TB is drilled 13/64 and my set screw is turn up quict a bit. If I lower the set screw it gets worse.
I wonder about this richness thing though because I never had the issue while I was lean but when I richened it up on the dyno to get peak power I started to notice the problem and now that the MAFT is completely off the car and it is a lot richer the problem is worse, so bad I have to use 2 feet when coming to a stop to keep it running.
I am running a 222/.534/114 cam.
My TB is drilled 13/64 and my set screw is turn up quict a bit. If I lower the set screw it gets worse.
I wonder about this richness thing though because I never had the issue while I was lean but when I richened it up on the dyno to get peak power I started to notice the problem and now that the MAFT is completely off the car and it is a lot richer the problem is worse, so bad I have to use 2 feet when coming to a stop to keep it running.
I am running a 222/.534/114 cam.
