Aem f/ic update

ok so a couple of items:

1. turns out my uego wideband has been off by 3 points mine is reading 17:1 while all others tested read 14 on my jeep so that has been a big part of my fight to tune this thing. since im tuning it stupid rich.
i think im just going to buy the NGK wideband instead of the AEM

2. my misfire at idle and spark blowout issue
FIX: new battery my old one failed load testing and would not charge past 80% after new batter these items have been fixed. i also placed new grounds.

3. random stall at idle: threw code for cam sensor replaced cam sensor no fix
FIX. new crank sensor from NAPA reset my computer and all has been fine and dandy since for 2 days
 
Good to hear you have found the gremlins. AEM uses a Bosch Sensor and now I have to ask how old is the failed Sensor? I do know they change over the years and have to be replaced on a periodic basis. I changed out both of my stock Sensors at 135,000 miles. I was a bit late on this change. And I did see a difference in the engine performance. In particular, my cold idle improved by a large margin and the mileage went up. Thing must have been running fat...

I made the changes prior to the Forced Induction. My thoughts were to provide the best environment for the tune by using all new Sensors.

I am still putzing with my tune and may just brak down and put it on a chassis dyno and get the fine tuning done. It is running well, pulls stumps and where I was not able to burn the P235/75 R15s before, I certainly can now. On the stock 3.55s.

That will be changing this week as my Currie 9" goes into the back with 4.56s in it. I have already changed the front. 33s (LTT285/75R16) will be going on. Should be "peppy"...
 
My sensor is about 4-5 months old but may have always been reading incorrectly. But for a little more than the replacement sensor I can get a whole new setup with a nicer sensor. And just remove it when I am not tuning.
 
Also I found a way around the part throttle o2 sensor issues. Just unplug them lol.
 
I suppose you could just run the O2 correction in the F/IC and no O2 Sensor... Not sure how that would work but it would eliminate some issues.

We has E15 here (E10 in the winter) and the desired AFR for E15 is 14.2, not 14.64. I realize that is a fine point but it still leaves the Heep running a tad rich.

When I do my E85 tune, I suspect I will need to override the stock O2 as it will want to see an AFR of 14.64 and not an AFR of 9.6... Should be interesting. The E85 project is in the distance as I have bigger fish to fry at the moment.
 
Thanks for the links. I can see how the 2006 might be different as the PCM is so different. Allegedly, all of the 96-04 Chryco PCMs are physically the same, only the programming varies by vehicle. The Viper used the same PCM hardware...

As a side note, I am in process of confiming the operation of "High Altitude Compensator (HAC)" switches. If they work as they appear to, I can install one and use it to shift the F/IC from a "low" altitude (sea level to 4k') and a "high" altitude (4k' to 14k') setups. By separating the psia range in two parts, I can get better resolution in the tune. Right now, my "B" map is for El Cheapo regular fuel (85 Octane here...) but it could just as easily be for the low altutude setup.

Hayabusa Motorcycles have them and I think I will call thier Tech Support and ask the question. From the Hayabusa boards, everyone says that the switch changes state at 4k' altitude. I have the "problem" where by my maps must have data in them to cover the operation from sea level (I visit Family in Cali) to 14,114' as I occasionally drive up to the top of Pikes Peak.

Some snowmobiles use them as well. Just need to find the part. Otherwise, I'll have to add an Altimeter into the Heep so as to know when to change over to the "B" map...
 
This altitude problem is part of the issue with using the AEM, supercharger and 1 bar MAP sensor. Having to switch between 2 different maps depending on the altitude sound like a pain. Sounds like 2 completely different tunes.
 
The AEM has a built-in 2.5bar map sensor, which you boost guys should be using. I have yet to connect it and am using the stock sensor to feed the aem map tables. Use the A table for your high alt and the B table for sea level.
 
Just to be perfectly clear...

I am doing two tunes. One for low altitudes and one for high altitudes. The purpose of this is to get better resolution inside of each tune. As things stand now, my tune covers from sea level to 14,000 feet of altitude. THis is due to my unique circumstances and not due to any fault of the F/IC. I already have two tunes living in the F/IC/ One is for higher Octane fuel and one is for the 85 Octane we have around here.

The F/IC has it's very own 2.5 bar MAP built in as is used by the F/IC to establish two things:
1) Starting Altitude. Just as the PCM does, the F/IC looks at the MAP voltage at ignition on and zero RPM. Gives it a starting point.
2) Reads the boost level.

The only 1 bar MAP in the system is the Jeep MAP. Separate issue entirely from the F/IC and totally non-related. Furthermore, it should not, ever, be connected to the F/IC. Call AEM if my word is not good enough.

On my post from earlier today, I have established that what I am looking for does not, apparently exist. There is not an off the shelf switch so I will have to make one the hard way out of a Factory MAP and a Comparator Circuit. I will start another thread for data collection.
 
Does't the AEM 2 bar and Stock 1 bar map sensors already adjust/set and compensate for altitude? Do you want separate tunes for low and high alt. and for low and high octane? That's 4 tunes? Doesn't the timing curve have more to do with the octane and the fueling curve with the altitude? Lower octane fuel requires more retard and higher alt requires less fuel?
 
Well the map sensors themselves don't do the Baro calculations, they read in PSIA which is absolute pressure. When you key on the ecu takes a reading of the map sensor and gauges it's altitude and shifts the fuel and timing tables to what ever altitude it thinks its at. It will also do this sometimes at WOT which can make things rather interesting if your at 6k feet and in boost when it does its recalc.
 
The F/IC operates under the parameters that the end user assigns to it. The narrower the range of PSIa, the better resolution the fuel and ignition maps have. This is obvious. As I must account for sea level to 14k', owing to my circumstances, my map resolution is thereby limited. Also obvious. By splitting the maps in twain, better control over the fuel/ignition will be achieved. Again, obvious.

At WOT, the XJ is in Open Loop and is ignoring just about every sensor on it. The only times the Heep is in Closed Loop is Idle and Cruise. Period. If the throttle is moved greater than what the Cruise Control System moves it, resulting in either Acceleration or Decelleration, the Heep goes Open Loop. This is not a debatable subject. Look it up. I have verified the operation with my OBDII reader. Only Closed Loop at idle or steady state throttle. Road speed is not a factor either. For the PCM, there is no difference between a 25mph "cruise" and a 75mph "cruise".

The PCM takes a snapshot of the altitude at start up. The logic is ignition on and zero RPM, pre-crank. Once the crank is initiated, the PCM "freezes" that altitude reading until the engine is restarted.

Look it up. All of this is right out of the Factory Service Manual.

With the Heep in Open Loop, it is the F/IC that will determine the AFRs and the Ignition. At least it will when using all 6 injectors. How well the F/IC manages the AFRs with the seventh injector remains to be seen. There was not any testing done by Boostec. They just bolted a F/IC in and called it a miracle cure.

IMO, the AEM F/IC product lines are one of the easiest systems to program when compared to others. The Perfect Power I had previously was not only a nightmare to actually program but, the ignition was completely locked away from the end user's adjustment. The only way to control detonation was to throw fuel at it until it stopped.

You have choices in the programming. Personally, I use percentage as it makes the math very straight forward when correcting the maps. If I need an 8% change to the AFR, I dial the cell by 8%. What could possibly be easier?

When I corrected the Speedometer (I use the F/IC8 (AEM part number 30-1930) just for this reason) I took the heep out to the highway, zeroed the trip odometer at a mile marker and drove 50 miles. Looked at the error, did the math, applied the -10.9% correction value in the frequency table and drove back confirming that it was now less than 0.1 miles off in 50 miles. I have since ran it a full 100 and the error is still less than 0.1 mile. That makes it less than 0.1% off... Not bad for a Heep running P285/75R16s with 4.56:1 gears.
 
sidewaysstarion said:
Well I did some poking around and on the 97-98 jtecs the accel enrichment timers are set to 0 in the code, while the 99-01 (jtec+) have it enabled.
Click to expand...

So what does that mean in practical use?
 
It means that the F/IC wil automatically enrich under acceleration thus mimicking the acceleration pumps on carbs.

It is interesting, to me, that the F/IC6 manual does not mention this feature but the F/IC8 manual does. Although the manual on the F/IC8 describes the feature and explains the setting, I have not been able to locate the setting. Will call AEM to resolve.

Unless I just missed the reference in the book. Could happen.

My suggestion to those jumping into the Fuel Injection Tuning Arena is to get books on the subject and bone up on the material. There is a ton of good documentation out there that explains, near as I can tell, every facet of injection principles.

Prior to my installation, I spent the better part of a month doing the research. As a result, I feel that my error free installation was the direct result. The F/IC has been a thing of joy to work with and I can recommend the product line to anyone.
 
o-gauge-steamer said:
It means that the F/IC wil automatically enrich under acceleration thus mimicking the acceleration pumps on carbs.
Click to expand...
He is talking about the JTEC PCM, not the FIC.
 
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