For the most part my Edelbrock E-Force #1593 is running well. I have put nearly 300 miles on it.

Lower RPM's when loading the engine such as hill I'm noticing a shtter or miss. I haven't really worried about it as it seemed minor but I set a code this time while lugging or loading the car heavely around 2200 RPM. It set code P0068 - MAP/MAF Throttle Position Correlation.

I contacted Edelbrock Tech Support and they are working on it. They had me send them my stock Tune checking to see if it truly was a stock tune. They said they are not having any drivability issues with their current tune.

I have checked for vacuum leaks, pinched wires or anything obvious. If anybody has any idea what else I should check please let me know as I would like to get this fixed.



'06 C6 A6 LS2 Bone Stock with 25000 miles

 

One possibility...pinched harness under the coil brackets.....

 

Would that cause a weak spark or total miss? However, tomorrow I'm going to pull the coil packs and double check for pinched wires.

I was hoping to hear back from Edelbrock but I guess it will monday or later.

Also, what plugs are people running with blowers?

 

Your symptoms would depend upon how crushed or cut the harness was. If it were completely cut you'd have a constant miss. Anything less than that and the symptoms would vary. In the guy in the photos case, the miss only showed itself under certain load conditions. I am not saying this is the problem but rather I am saying this is a possibility and you should doublecheck your work.

You'll get a dozen different answers on your spark plug question but for your application the stock plugs are fine as long as they are in good condition. I ran NGK Iridium TR-5IX gapped to .040. I also ran a set of heavy Taylor "Thunderbolt 50" plug wires.

 

Definitely check those coil harnesses first!! I spent about 20 hours trouble shooting before finding that problem on my car.

 

Thanks a lot for the advice. That's what I'll be doing this morning.

I'll let everybody know what I find.

 

Good news is I did a jam up job. Wires and connectors routed neatly, cleanly and no chaffing anywhere. I also check the injector wiring and all good. I also looked inside all connectors for bent or dislodged pins.

The bad news is I'm back at square one waiting on Edelbrock to analize my stock calibration. Lets cross our fingers that a new tune from Edelbrock does the trick.

Vacuum leaks can effect low and mid performance greatly. This is a concern of mine. I have checked just about all vacuum connections and they all look good. However, that doesn't prove one doesn't exist. An old way to look for vacuum leaks is propane and an RPM monitor. Does anyone else know of a better way to check for vacuum leaks other than propane?

 

Code P0068 is related to airflow. Too much is detected I believe. The only thing I can suggest is checking all the wiring (maf, map, etc). Also make sure the air intake and throttle body are properly connected and tightened.
Good luck and let us know what you find out.

 

Checked'em all out and they are good.

I took it for a drive today (50 miles) and it ran darn good but right when I was almost home I pulled out and gave it about 3/4 throttle and it bucked as if you were moving the accelator up and down really fast. I let off the gas so it wouldn't set another code but if I would have jammed it on to the floor it would have halled *** and seemed ok.

I might look for some vacuum leaks tomorrow but I think the calibration need tweeked from Edelbrock.

I certainly will let everybody know what I find out.

 

Checked for Vacuum leaks and didn't find any. Checked all around the TB and ducting. I also checked the direction of the MAF sensor and it was right. I don't know of anything else I can do other than wait for Edelbrock to get back to me.

For anybody that wants to know I monitored the butterfly that equalizes pressure in the blower to save gas. It stays shut to about 1/3 throttle and then snaps open quickly.

 

I think it is fixed (maybe). Edelbrock asked for my stock tune and after receiving it said my stock tune was indeed stock and was not the problem. They asked me to log some data. While data logging I loaded the car heavely and did everything I could to make it stumble but it would not. If it behaves itself for the rest of the holidays I'm callig it fixed.

I have a theory. The vacuum inlet for the active exhaust was suppose to be capped if you don’t have the active exhaust option. I don't have active exhaust but I did notice there was no cap present. I hunted for something to plug it with and found a hose that would fit and then plugged the end of the hose. Well, the hose split leaving a vacuum leak and I drove with it for about 100 miles before finding the split. I replaced it with a rubber vacuum plug like I should have done in the first place. Now it seems every time I take it out it does better. I believe it is the block learn or fuel trim table that is slowly dialing in.

Is this normal to not get 100% open throttle?



Are the abberations on the boost curve normal - Red Line Boost /Blue line RPM
Notice boost is starting to come in at 1000 rpm.

 

Yeah, that boost curve is normal with the E-Force.

 

More Problems -
Went to the track but of all the luck got rained out but I did find out a few things. First off it's not running good at all. The trip to the track is 115 miles. At some point I set two codes P0171 and P0174, running lean. I reset the codes at the track. I found out I can't hammer the throttle at a dead stop or it will darn near die, best called a severe stumble I guess. I never got a chance to log any data at the track at all but I did log a little going home.

Headache #2:
Another problem that just started happening is when I come to a stop the transmission will downshift into first gear and cause the car to jerk at about 10 mph. This might be an unrelated problem but a fast idle could cause it I suppose.

Anyway, here is some data that might show a lean condition but I need a pro to look at it and tell me for sure. Most of all I need a plan for troubleshooting. It sure acts like a vacuum leak to me but I can't find one. Back in the old carburators days propane would cause the engine RPM to increase. I tried this but did not see an increase. Edlebrock has been helpful but they are toooo slow for me. Every communication takes two days.


The fat blue line is RPMand the other two are the fuel trims. On the left are the fuel trim values and on the right is the RPM

 

I would be very carefull driving the car and wouldnt push it hard until you get this sorted out. Everything you are saying points to a lean condition of some sort. Could be a fuel or an air (maf) issue.
Hard to tell if its a tune or mechanical issue. Unless you could get the tune in hptuners I would have no way to even look at it.
I'm sure edelbrock will get you sorted out. Just might take time.

 

Any chance you rolled one of those 8 manifold to head o-rings during the install?

 

Quit wasting your time waiting on edelbrock to tune it....they suck. This is a tuning issue, plain and simple. Take it to a real tuner and he'll sort you out.

 

Truthfully, Edelbrock I believe is trying to help but they don't know how to tune and they are like the middle man in this effort. I send them the log files and they send them to SCT. Hell, I guess they do suck a little.
This worries me somewhat as SCT is big winner with Ford enthusiasts and if you go to their site it is heavly weighted with Mustang stuff. So could I expect a whole hearted responce from them - who knows?

As far as tuning being an issue I agree 100%. Today I was able to run mounds of data using SCT Live Link Gen II data logging software. It's telling me I'm on the lean side even when I'm fully loading the engine. I also looked for vacuum leaks again today and I would bet the bank I do not have a vacuum leak! I believe the A/F just needs fattened up and all would be well.

Thank you for offering to recommend a good tuner. However, if you knew me you would know I like doing everything myself and that I'm wanting to learn to tune the C6's myself anyway. I'm very capable of doing the tune as I have tuned C4's for years. I understand the process. I just don't know anything about the C6 ECM or newer tuning software or what are good data log numbers. Mentally I keep comparing them to C4 numbers and that is just confusing. I suspect I will end up buying HP or EFILive and asking for lots of help on the forum until I get the hang of it.

I live up in Northeast GA. pretty much no mans land. Who would you recommend around here or fairly close by just in case hell freezes over and I let someone else fix it?

 

Before you go too far down the "tune is crap" road I would ask myself why this very tune has worked in dozens upon dozens of identical otherwise stock cars without issue.

Best of luck in resolving the problem.

 

Sleeper, if you pm me your contact information, I can get with you offline and we can discuss your issues.

 

Hard to say really. There is a guy running an eforce locally here. The tune he got didn't work well and had to redirect to a custom tune. The "canned tune" edelbrock puts out is for a stock application. The moment you add things like a different cam or head work the "shelf" or "canned" tune is obsolete and should not be used.