Pay2play killa

Alright; so i'm having one hell of a time with this AEM box. This is the 3rd honda box and my 5th aem to tune so i'm not a total n00b but not as familiar as i'd like to be. This box is on an integra with a built GSR turbo running a stock obd1 distributor (repinned veri w/ stock ecu w/ 1000cc 3 bar basemap in crome), gm 3 bar map and 1000cc injectors going through an oe reisistor box.

I've had nothing but problems getting this thing to start and run and idle like a normal car with this AEM. To start off initially it was hard to get the car to start with long crank times and hardcore kickback while cranking. When it finally did start it was hard to keep runing; if rpm dipped below 1100rpm the car would loose stat sync and die. I played around with resistor values with no success (r2 and r4 for cam/crank attenuation tried using 2k ohm from 1kohm on adv from a more experienced tuner but put the 1k ohm back in); finally decided to idle it up to 1500rpm and headed to the dyno. Things were going good on the dyno minus the car not wanting to start for **** (no its not fuel values its sync issues) power was good all was well until we blew a coupler at 15psi. No biggie took the car off fixed the coupler and went home happy.


Decided to make the car start/run/idle normal so I tried 3 other distributors and wound up with one with the LEAST issues... but still not perfect car still wont start run and idle like normal so I got so fed up and i flashed with the 1.21 firmware (even though i know its not any improvement over 1.19) with a untouched converted honda startup cal w/ all the sensors and injectors set to this car that seemed to help some but then after getting idle AFRs in check and then stoping/starting the car the same issues popped up... so I downgraded the firmware on the aem to 1.19 and reloaded the cal was using...........

The issue now is i have the car starting with the key (no gas pedal) and idleing ok (had to turn up the high/low crank cam sensor setting to 1500rpm to do this any lower it still stalls) but 9/10 times you start the car ignition timing is locked to about 10 degrees AFTER TDC, i know this as i tried w/ a timing light and the line is about 10 degrees after tdc but yet the aem and logs show the timing is reading off of the maps (numbers moving) but actual timing does not change. the car barely revs and obviously wont move or make power. The 1 time it starts all is great; it starts idles and drives good and makes tons of power (well put together setup)... it's the fact that it wont sync right 9/10 times that is bothering the hell out of me... Twice when it started like this it cleared up on its own but i couldn't get a log of that happening.

anyway i posted some internal logs with all the values i found in another thread and my cal so maybe someone can tell me if its fixable within the cal or if this box is just defective (after exhausting all other troubleshooting methods i've stumbled across i'm betting on the latter).

Anyway if anyone can help you'll be my new hero!


(this was copy/pasted from the AEM forum btw)

Tony the Tiger

If swapping out dsitributors didn't solve the problem, have you tried to verify this with a genuine OEM Honda distributor? I've had similar situations in the past with aftermarket distributors, and one particular case, I've solved a huge idle/misfire/bogging problem by sourcing an OEM distributor off a D16, and then solder and transfer the OEM Cam/TDC/Crank maganetic pickups onto the aftermarket housing (B-series OEM dizzy;s were hard to find).

The other issue could be a grounding problem.. Whenever your grounding system is deteriorating, the engine itself (block/head/IM/etc) also loses grounding. As you know, whenever you deal with sensitive low voltage wires, it is always suggested to run sensitive along heavy sources of ground (along the frame rails, chassis, etc..) because a heavily grounded area can help shield a wire from interference. If you haven't checked on your entire grounding system, go do that now and see what happens. I'd replace all the factory grounds with better ones, and then add a few more at critical locations like the alternator housing, right beside the distributor, and one on the intake manifold. A well grounded engine will become a "shield" for signal wires, thus, highly reducing any chances of electrical interference for your crank/cam signal wires.

If you have ruled out the EMS itself not being a problem, and also ruled out the distributor not being a problem, it has to point to the grounding, or wiring related. Hope this helps

Pay2play killa

yea we went over grounding; engine is well grounded to sanded spots on the unibody same w/ the battery both heavy gauge wire; ecu is well grounded no corosion anywhere. all the distributors we tried w/ the exception of one is an OE (not new but oe) one of the middle ones was an autozone special.

I even tried closing the gaps between the magnet wheel and the VR sensor in the original distributor to no avail....

talked to another guy today whos also more famiar w/ the aem thani and said he's seen taht in a few boxes and usually AEM fixes them so i'm now convinced its a fauilty box; still just wanted some input... i'm calling/emailing tech tomorrow to see how much an out of warantee repair will be but will probably wind up going back to crome as we have a race to get to this upcoming weekend and this EMS was destined to run a 1jzgte in an mx73 cressida to begin with

JDogg

see if you can find someone to borrow an msd distributor from or an orignal oem distributor thats on a car. You can not buy a brand new distributor anymore, they are all reman's and junk

you can change the resistor for the cam/crank sensor inside the box for a higher value and that will help it produce a stronger signal. It may not completely fix it but it will help.


if you can get the car to run, log rpm, t2per and cam-crank.

t2per and cam-crank should be nice smooth lines, if you see any sharp breaks or the line is very jagged, then the distributor is your problem.

I had a prelude a while ago that was doing the same thing, it took 7 distributors before we found one that wasnt a pile of crap.

Pay2play killa

i did log all that its in my logs; lines are very jagged...

you should not have to go through 7 distributors to work with this ems... each dizzy we tried runs my car (very similar setup w/ gsr head obd1 on crome) no problems, fires right up no hiccups no long starts)

AEM really should have done a better job with honda boxes working W/ VR sensors better; you shouldn't have to go to a hal effect setup but meh i degress...

aem box is being returned to its owner and we're redoing the motor on crome pro gold firmware

JDogg

the problem isnt the aem, its shitty cam/crank sensors. if you have a **** signal going in you will have a **** signal coming out.

a honda ecu will run the car, but a distributor with out those issues will run it better.

you can change the cam/crank resistors in the ems to a higher value to try and get a higher voltage signal in, that may help but usually only at low rpms.

the magnetic sensors generate their own voltage that goes up with rpm, if you have a break in that its a sensor issue.

all standalones work better with a hall effect sensor.