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Old 04-11-2014   #71
Mitsumark
 
Join Date: Aug 2013
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Default Re: My last effort

Yes..I did try to run the oil right at the add mark..It didn't help..To answer a couple of the above questions..Yes the current chip is a Haibeck canned tune for my mods and IAT relocation..I spoke to Marc asking if he thought maybe something needed tweaking and he said his tune has no effect at idle and even below 50% throttle....I took that as the stock parameters are left alone until the throttle is more than 50%..Now remember that the majority of smoke it at idle..It does throw out some smoke under heavy throttle but it isn't nothing I haven't seen when dropping the hammer on most high power cars..My concern is not the smoke under load..It shouldn't be smoking at idle..This is exactly what goes on in sequence..Car starts up cold,no smoke at all..Once warm it will start to smoke at idle..Upon acceleration it has plenty of power,no hesitation..Coasting down to stop,once in neutral the motor will start to hunt from 400-1200 RPM and sometimes even feels like its gonna stall but doesn't..During this hunting it feels like the car is choking on fuel and smoke smells strong like fuel/oil mix..Once fully stopped the idle smooths out..When I told Marc the plugs keep fouling and I think it's running way rich,he responded with the following..

> > What is the idle speed when the engine hot? It should be 750 rpm. The calibration is designed for a stock manifold vacuum of 40 kpa. You should measure the manifold vacuum. If it is over 50 kpa, the MAP sensor will add so much fuel that the oxygen sensors can't control it and the engine will run rich for fuel at idle and under 2000 rpm.
>> >
>> > If you use a data scanner to read the manifold vacuum, also record the Block and Integrator fuel trims for each bank and let me know.

Now I don't have the diagnostic tools to do this,nor do I even know what some of it means..I'm guessing it has to due with Idle counts,AFR,ect..

Lee-I didn't call Dominic as I didn't want to spend money on another chip as I'm not sure if that's even the problem..I borrowed a stock chip from Dave Johnson(Thanks Dave) and the hunting still pursued, smoke was much less but still present..Granted this was for a bone stock 91 350 car..Car also had no gonads with the stocker..

As far as selling it,,I really don't want to but I think if someone came to me with cash money right now,I'd probably let her go..The only way this car will ever run correctly is if it finds it's way to Chicago because there is no one around here and I honestly don't want to touch it anymore...Hey Frank--When exactly are you going out there?Im brainstorming..

Last edited by Mitsumark; 04-11-2014 at 09:21 PM.
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Old 04-12-2014   #72
Mitsumark
 
Join Date: Aug 2013
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Default Re: My last effort

Guys I just thought of something..Is it possible that the very first chip the car was built with(B Kirchoffer)was tuned to always run open loop?Is that possible?Hmm..No smoke when cold,no surging,better idle...Seems and soon as the car goes closed loop the smoke and surging starts...I also remember the RPM was set to 1000RPM with the original Kirchoffer chip for better idle due to Jeal cams and to cut down on flywheel noise..I wonder if Vette Docs tampered with the TB screw to match the chip calibration...I'm now running a Haibeck chip with 750RPM idle but haven't touched the idle screw..Sounds confusing but does anyone understand where I'm going with this?
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Old 04-12-2014   #73
Blue Flame Restorations
 
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Default Re: My last effort

Yes. Your theory "may" have validity??


I only see two variables that you changed prior to the issue besides your plenum pull. I would change them back one at a time and evaluate with each change.

If those two variables do not prove to be at fault, I'd pull the plenum again and do a thorough inspection, including the gaskets for damage.
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Old 04-12-2014   #74
mike100
 
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Default Re: My last effort

Maybe the 02 sensor is broke and sending garbage values to the ECM.
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Old 04-12-2014   #75
Mitsumark
 
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Default Re: My last effort

02s are brand new..As of 900 miles ago..With all the smok she's been blowing wouldn't be surprised if they are ruined already..
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Old 04-12-2014   #76
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Default Re: My last effort

Quote:
Originally Posted by Mitsumark View Post
Guys I just thought of something..Is it possible that the very first chip the car was built with(B Kirchoffer)was tuned to always run open loop?Is that possible?Hmm..No smoke when cold,no surging,better idle...Seems and soon as the car goes closed loop the smoke and surging starts...I also remember the RPM was set to 1000RPM with the original Kirchoffer chip for better idle due to Jeal cams and to cut down on flywheel noise..I wonder if Vette Docs tampered with the TB screw to match the chip calibration...I'm now running a Haibeck chip with 750RPM idle but haven't touched the idle screw..Sounds confusing but does anyone understand where I'm going with this?


If the issue is/was fuel closed loop would have less smoke since the ECM would have some control,if oil issue is something else like guides/seal,rings etc, then closed or open would not make a difference.

On the Idle you are right if the TB screw is adjusted for 1000 rpm and the chip is programed for 750 this will cause what you are experiencing.
Idle should not effect oil issue.

Pete
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Old 04-12-2014   #77
XfireZ51
 
Join Date: May 2007
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Default Re: My last effort

Quote:
Originally Posted by Mitsumark View Post
Guys I just thought of something..Is it possible that the very first chip the car was built with(B Kirchoffer)was tuned to always run open loop?Is that possible?Hmm..No smoke when cold,no surging,better idle...Seems and soon as the car goes closed loop the smoke and surging starts...I also remember the RPM was set to 1000RPM with the original Kirchoffer chip for better idle due to Jeal cams and to cut down on flywheel noise..I wonder if Vette Docs tampered with the TB screw to match the chip calibration...I'm now running a Haibeck chip with 750RPM idle but haven't touched the idle screw..Sounds confusing but does anyone understand where I'm going with this?
The reason tuners use Open Loop w larger cams is because they don't deal w the cam overlap and how that affects the O2 sensor readings. The ECM thinks the motor is running lean due to the fresh air going past the O2 sensor. It's an issue at idle but generally not anywhere else. If the ECM IS "trying" to get to a 750rpm idle(depending on the cams probably not going to run very well) it will attempt to do that but likely invoke the stall saver as the engine begins to falter.
If the stall saver values haven't been changed, they can produce wild swings on a cammed motor since they were meant for stock cams.
Do you KNOW if VD did adjust the Min Air settings? otherwise the cal could just have had idle set for 1000rpm.
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Old 04-12-2014   #78
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Default Re: My last effort

The more and more that I think about it, the more I think this could be a simple tuning issue..

Xfire..I don't know if they did the min air adjustment..Ive heard the term here before..Also what does that entail?Car was built sometime in 03 and it states on the build sheet"customer must return after break in for further tuning"..Don't know if the original owner ever returned as I don't have anything in my documents that says he did return..I am sure that after the build the old owner trailered this thing around the states and drove the car in road race events which tells me there were no problems after his build.Car was raced from tracks in Connecticut and as far as Vegas .There were no problems after I got it either..I drove it home from Virginia to NJ (4hrs) without a single hiccup..As stated in another thread,,I hated the 1000RPM idle as getting out of 1st was a little difficult with the aggressive clutch in the car,,it was drinking gas to feed the 1000RPM idle,,and lastly it was obnoxiously loud sitting in traffic..Once I removed the tune and sent it out with the request of a lower RPM along with a list of my mods,installed it and the car went bonkers..Last week I pulled the plenum to check for oil and vac leaks and wound up yankin the secondary stuff,installing new MSD coils and Magnecore wires..Today I have to ship the chip back to Marc for him to recalibrate for no secondary's...I'm gonna also request he bumps the idle back up to 1K and see what I get...It is very possible that this is all something simple..Problem is I don't have the diagnostic tools or the know how to isolate the problem..
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Old 04-12-2014   #79
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Default Re: My last effort

Pull the chip and make sure that the pins are all lined up correctly.
Again, where are you in NJ ???
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Old 04-12-2014   #80
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Default Re: My last effort

Send you r address to me i will send you my chip
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