Tip swap idle problems
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Tip swap idle problems
just wrapped up my tpi swap, car is a 90 formula originally tbi. Used an unmolested engine harness from hawks.
Car fired right off, I set base timing at 6 degrees with the est bypass disconnected at the firewall, all is fine.
Shut the car down, wait a few minutes, reconnect the est bypass and fire it off and the car immediately goes to 3500rpm and stays there. It’s throwing a ton of timing at it as soon as I give the ecm control of the timing again. Any suggestions? I’ve ruled out iac, I can close it manually and leave it unplugged and it still skyrockets in rpm. Car had a stealth ram on it, fresh iac, tps, etc. thanks in advance
Car fired right off, I set base timing at 6 degrees with the est bypass disconnected at the firewall, all is fine.
Shut the car down, wait a few minutes, reconnect the est bypass and fire it off and the car immediately goes to 3500rpm and stays there. It’s throwing a ton of timing at it as soon as I give the ecm control of the timing again. Any suggestions? I’ve ruled out iac, I can close it manually and leave it unplugged and it still skyrockets in rpm. Car had a stealth ram on it, fresh iac, tps, etc. thanks in advance
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Re: Tip swap idle problems
you nailed it. Forgot to post an update, I bought the HSR used and assembled from a local guy who couldn’t get his car to idle. Figured he had tuning issues. I pulled the plenum to reseal it and found there’s a vacuum port in the middle of the plenum, on the bottom. It was wide open....put a 3/8” npt pipe plug in it and all is well!
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Re: Tip swap idle problems
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Re: Tip swap idle problems
Thanks for the heads up. I’ve been working with Scott Hansen on the base tune, going to do some logging and have him finalize it. Then I’m on my own, this is a little 355 blower motor with a vortech Head unit. Going to hack around it for now, picked up a 6btm and an fmu. Will be temporary until I make sure the car works and then I’ll probably do one of the efi connection setups and an lsx ecm. I already have hp tuners for my ls stuff, just didn’t want to invest much into hardware in tuning the sbc not knowing if it’s going to stay in the car or not. Was one of those things where I blew it up but was so deep into the small block setup I stayed with it for now. Actually traded my blow through 750 for the whole stealth ram setup, harness was $300, figured it’d be cool to have all my factory stuff work again. We’ll see, may even keep the 730 in it if it doesn’t throw a fit with 7 pounds on it. Just have to fool the map one way or another, probably with a temporary hack job check valve haha
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