:::RHMT::: Real Home Made Turbo
General Category => Engine Management => Topic started by: snm95ls on September 19, 2009, 10:54:10 PM
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The odd lean missfire at idle is getting under my skin. I really didn't like the idea of running them with a resister box in the first place even though people have been doing it for years.
I just ordered a DIY P&H driver board from jbperf.com.
Hopefully all works out well.
Anybody on here tried one out?
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If you can't get DSM 450cc to idle like butter a P&H driver box won't help you.
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But, to answer your question, those are exactly the daughterboards I planned on using with the next set of 1600cc injectors I touch.
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If you can't get DSM 450cc to idle like butter a P&H driver box won't help you.
Ok.
I'll just burn the motherfucker to the ground then.
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You think they might be old injectors and not flowing so hot anymore? Does the idle start popping when you turn the headlights on, etc?
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You think they might be old injectors and not flowing so hot anymore? Does the idle start popping when you turn the headlights on, etc?
JD, I had them cleaned and flow tested by Injector Rehab.
I notice it more when the outside temps are high. To me that says that the small pulse widths needed for my particular combo do not mesh well with a shitbox resister pack and P&H injectors.
I could easily run in open loop all of the time and get to idle butter smooth with an ever so slightly rich A?F, but I am not interested in doing so.
It is a bone stock A6 in an STD, with a wire harness that I had to fabricate because of a botched MPFI conversion from a previous owner.
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Hot IM can cause the fuel to fall out or evaporate to a different degree. Add in what I am ASSuming is a one wire O2 and I guess AFRs at idle are going and getting themselves fucked.
Jared Deskins swore by converting the older cars to 4 wire O2 a decade ago, said it made the idle better and picked up mpg. Maybe you should try that first?
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Hot IM can cause the fuel to fall out or evaporate to a different degree. Add in what I am ASSuming is a one wire O2 and I guess AFRs at idle are going and getting themselves fucked.
Jared Deskins swore by converting the older cars to 4 wire O2 a decade ago, said it made the idle better and picked up mpg. Maybe you should try that first?
Forgot to mention it is a hard wired OBD1/MPFI conversion.
So no 1 wire oxygen sensor.
The A/F at idle is fine until the little lean missfires here and there. The permanently installed WB shows these quite well as the A/F will jump to mid 15s pretty much in time with the missifre.
It is not a constant deal. Just when ambient temps are above about 75°F.
I have not bothered to check IAT readings.
I guess the root problem could be ignition based, but I highly doubt it. The only change in the combination has been the addition of the DSM 450s and a retune to compensate.
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It's something in the fuel or ignition system, got to be.
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It's something in the fuel or ignition system, got to be.
Dunno man.
The fuel pressure is within spec. The maps do seem to be a bit oddly shaped to me, but I dunno. I would upload the .bin right now, but I don't feel like booting up my tuning laptop to do it.
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What gap are you running on your plugs? What heat range? And what's wrong with a slightly rich idle? Mine idles 11:1 till it's hot, then it's 12:1. I'm running 20* advance at 700 RPMs, 22* 1000 RPMs, holds strong vacuum, purrrrrrrs.
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What gap are you running on your plugs? What heat range? And what's wrong with a slightly rich idle? Mine idles 11:1 till it's hot, then it's 12:1. I'm running 20* advance at 700 RPMs, 22* 1000 RPMs, holds strong vacuum, purrrrrrrs.
Stock NGK plugs with the gap set to .041". NGK plug wires. It is not a secondary ignition problem since it does not exhibit the typical symptoms of such an issue.
Even the wiring for the CYP sensor is shielded as it would be on a stock harness.
I don't care to run a slightly rich idle because on a stock engine, I don't like melted catalytic converters, and it is a band aid fix IMO.
Jesus guys. You act as if I am spending several hundred dollars on this little project. It isn't like I am buying an FJO or AEM injector driver.
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What advance are you running at idle? Just saying if it's a spec too lean from injector latency, just pull a couple degrees of timing out in the problem cells, dial in a spec more idle, done. Especially if you're running a kinda advanced idle already.
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Jesus guys. You act as if I am spending several hundred dollars on this little project. It isn't like I am buying an FJO or AEM injector driver.
No, I am acting as if there is something wrong with not being able to get 450cc injectors to idle like stock. Almost as if there's something wrong with your car, possibly on a basic level that could cause your engine to shitcan itself when boost gets applied.
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Jesus guys. You act as if I am spending several hundred dollars on this little project. It isn't like I am buying an FJO or AEM injector driver.
No, I am acting as if there is something wrong with not being able to get 450cc injectors to idle like stock. Almost as if there's something wrong with your car, possibly on a basic level that could cause your engine to shitcan itself when boost gets applied.
Ok.
Probably so.
I will investigate further when time allows.
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Jesus guys. You act as if I am spending several hundred dollars on this little project. It isn't like I am buying an FJO or AEM injector driver.
No, I am acting as if there is something wrong with not being able to get 450cc injectors to idle like stock. Almost as if there's something wrong with your car, possibly on a basic level that could cause your engine to shitcan itself when boost gets applied.
true these injectors should idle mint try playing with your other tables like the iat or mabey ect idle offset i dunno the gap also seems kinda big to me for a turbo set up.
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Jesus guys. You act as if I am spending several hundred dollars on this little project. It isn't like I am buying an FJO or AEM injector driver.
No, I am acting as if there is something wrong with not being able to get 450cc injectors to idle like stock. Almost as if there's something wrong with your car, possibly on a basic level that could cause your engine to shitcan itself when boost gets applied.
true these injectors should idle mint try playing with your other tables like the iat or mabey ect idle offset i dunno the gap also seems kinda big to me for a turbo set up.
There is no turbo yet, and the only issue is at idle. Factory recommended spark plug gap is 0.039"-0.043"
Pulled the current BIN off my ECU, and the pulse widths are somewhat large even compared to a stock map running stock injectors. Looked at my old map with the stock sized injectors and the pulse widths are large as well when compared to a stock map with stock injectors. Apparently there is some issue with the fuel side.
Oh well. Guess I will have to check fuel pressure, yet again, and then maybe try a high current(relatively) voltage drop across each injector circuit.
Maybe the resistor box I have is FUBARed somehow.
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Jesus guys. You act as if I am spending several hundred dollars on this little project. It isn't like I am buying an FJO or AEM injector driver.
No, I am acting as if there is something wrong with not being able to get 450cc injectors to idle like stock. Almost as if there's something wrong with your car, possibly on a basic level that could cause your engine to shitcan itself when boost gets applied.
true these injectors should idle mint try playing with your other tables like the iat or mabey ect idle offset i dunno the gap also seems kinda big to me for a turbo set up.
There is no turbo yet, and the only issue is at idle. Factory recommended spark plug gap is 0.039"-0.043"
Pulled the current BIN off my ECU, and the pulse widths are somewhat large even compared to a stock map running stock injectors. Looked at my old map with the stock sized injectors and the pulse widths are large as well when compared to a stock map with stock injectors. Apparently there is some issue with the fuel side.
Oh well. Guess I will have to check fuel pressure, yet again, and then maybe try a high current(relatively) voltage drop across each injector circuit.
Maybe the resistor box I have is FUBARed somehow.
what ohm do your injectors measure and what ohm are the resistors you're running? IE-what's the total resistance the ecu is seeing.
FWIW, I'm running low ohm RC 550s, with resistors wired in, running 62 PSI base fuel pressure( never changes, returnless system), and they idle fine. I can (and have) idle 15:1, no problems, but I choose to run richer for other reasons.
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Jesus guys. You act as if I am spending several hundred dollars on this little project. It isn't like I am buying an FJO or AEM injector driver.
No, I am acting as if there is something wrong with not being able to get 450cc injectors to idle like stock. Almost as if there's something wrong with your car, possibly on a basic level that could cause your engine to shitcan itself when boost gets applied.
true these injectors should idle mint try playing with your other tables like the iat or mabey ect idle offset i dunno the gap also seems kinda big to me for a turbo set up.
There is no turbo yet, and the only issue is at idle. Factory recommended spark plug gap is 0.039"-0.043"
Pulled the current BIN off my ECU, and the pulse widths are somewhat large even compared to a stock map running stock injectors. Looked at my old map with the stock sized injectors and the pulse widths are large as well when compared to a stock map with stock injectors. Apparently there is some issue with the fuel side.
Oh well. Guess I will have to check fuel pressure, yet again, and then maybe try a high current(relatively) voltage drop across each injector circuit.
Maybe the resistor box I have is FUBARed somehow.
what ohm do your injectors measure and what ohm are the resistors you're running? IE-what's the total resistance the ecu is seeing.
FWIW, I'm running low ohm RC 550s, with resistors wired in, running 62 PSI base fuel pressure( never changes, returnless system), and they idle fine. I can (and have) idle 15:1, no problems, but I choose to run richer for other reasons.
Dunno. I need to check out the resister box. The resistance of the injectors measured out to be about 3.3-3.4 Ohms when they were serviced.
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Exhaust leaks, causing the wideband to read lean and therefore the tune to go rich?
Let the car idle for a couple minuts, pull plugs and look at them.
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Exhaust leaks, causing the wideband to read lean and therefore the tune to go rich?
Let the car idle for a couple minuts, pull plugs and look at them.
It would have to be a pinhole exhaust leak at just the right location. I run a very quiet exhaust system, and a leak large enough to affect the whole map would be pretty significant, therefore audibly noticeable I would think.
I will try it later when I need a break from working on homework.
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Resister box measures 6.1 - 6.3 Ohms.
13.3 Volts at measured between the input B+ at the resister box and grounded at the intake manifold.
14.4 Volts between the terminals on the battery.
I can get rid of the lean missfire by upping the idle speed quite a bit. Tach normally reads ~ 650 RPM, datalogger usually reads about 720-770 RPM at idle.
I tried a quick ghetto tach by using the frequency input of the DVOM I was using. I was getting a reading of 240 Hz. which should be about 460 RPM. Dunno how accurate that method is or the meter in that mode, but I know damn well it does not idle at 460 PM. lol.
I opened up the idle air bypass screw until it smoothed out, besides the slight surge, and it was about 950 RPM according to the tach. I don't care to idle at that speed on a stock camshaft as there is absolutely no point.
Didn't pull the plugs either. I will try to do so tomorrow, but I can't imagine an exhaust leak causing it to run rich and giving a lean missfire. It just doesn't add up.
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What timing does the engine idle at?
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90% of Honda engines idle at 16 degrees, the later D-series were 12 and some F/H ran 17/18.
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What timing does the engine idle at?
16.5 on the map.
Middle mark on the damper according to the timing light.
I really do not think a stock cam with unaltered camshaft timing would exhibit such behavior(the lean missfire) only after changing injectors. If alterations to the ignition timing is needed, then it is a band aid.
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Oil contamination perhaps? I've noticed, on higher compression engines, that if the valve seals are fucked or just burns some oil, the car doesn't like to idle at anything over 13.5:1(varies from car to car, of course). And this is on stock injectors.
My 450's idle like a champ at 14.5 @ 850rpm on my H22. Stock resistor box(accord).
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Oil contamination perhaps? I've noticed, on higher compression engines, that if the valve seals are fucked or just burns some oil, the car doesn't like to idle at anything over 13.5:1(varies from car to car, of course). And this is on stock injectors.
My 450's idle like a champ at 14.5 @ 850rpm on my H22. Stock resistor box(accord).
This engine is pretty damn healthy, and I doubt thee is any abnormal amount of oil entering the combustion chamber. I will pull the plugs when I get a chance and post pictures.
On stock injectors, this little issue did not exist.
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My 450's idle like a champ at 14.5 @ 850rpm on my H22. Stock resistor box(accord).
Same thing here, no issue at all. I use the resistor box from my deceased 91 teg.
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i plugged my dsm 450's in (plug-n-play)
and they've been great for me so far.
rich if anything.
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your whole problem is probably just battery offsets and iat ect compensation.
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your whole problem is probably just battery offsets and iat ect compensation.
I worked over the battery offset tables when I did the tune. I thought that I was running just a standard offset table until I compared my current tables to that of the stock Honduh 240 cc injector tables and that of the 1st gen DSM tables provided in Crome.
The issue seems to be related to ambient air temps and not ECT. I could be off my rocker though.
I would gladly upload my bin, but I tried to do so earlier, and got an error message stating that the upload folder is full.
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your whole problem is probably just battery offsets and iat ect compensation.
I worked over the battery offset tables when I did the tune. I thought that I was running just a standard offset table until I compared my current tables to that of the stock Honduh 240 cc injector tables and that of the 1st gen DSM tables provided in Crome.
The issue seems to be related to ambient air temps and not ECT. I could be off my rocker though.
I would gladly upload my bin, but I tried to do so earlier, and got an error message stating that the upload folder is full.
why not wait until it's the right weather to cause the problem and then fiddle with the iat compensation it's probably go away you could also try disabling the barometric pressure switch
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Which injector driver board did you go with? let us know how it works when you get it.
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Which injector driver board did you go with? let us know how it works when you get it.
V1.1B
http://jbperf.com/p&h_board/index.html (http://jbperf.com/p&h_board/index.html)
Will do. The main intent of the thread was to get some input on the board, if anybody had used one, and to serve as somewhat of a review. Granted I do not have a set of large by huge P&H injectors to play with, so the results could be somewhat skewed.
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I don't think the results will be skewed, at all.
A lot of the available driver boxes have a minimum allowed pulsewidth that's based entirely on dumb current limitation circuitry, and it causes nasty on/off jerky fluctuations in 1600cc injectors at light throttle. I'm confident that you will get something better out of that daughterboard.
I really want to see you do this. I've looked at those same boards in the past and thought to myself, Fuck Yeah! I just don't think that an injector driver is your problem.
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I worked on this problem a little today. Turns out that I forgot to reprogram the LC-1 to match up with my display, thus what I was seeing on a day to day basis, was reading richer than what the Wideband was reading. It was idling around 16.5:1. No wonder there was a lean miss. :mexi: I fiddled with the analog output of the LC-1 to try to replicate a narrowband output. since Innovate's default setting wasn't doing the trick. I managed to get the ECU to alternate between about 14.2 and 15.1 when fully warm and in closed loop operation.
Tried lots of little tweaks here and there such as the ones mentioned by others in the thread. It seems to be much more stable at idle now, but because of my gross changes to the battery offset table, I need to spend more time fine tuning the rest of the fuel map again.
Still pretty interested to see how the P&H driver board works out.
I also think I will be adding another O2 bung since I think a stock Honduh oxygen sensor will be much better with closed loop operation. I don't like the amount of time spent on the rich side of stoich with how the LC-1 is configured right now. Dunno if anybody has logged a stock sensor compared to a wideband to get a voltage/ lamda slope or not. I honestly haven't looked into it much.
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Good work.
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The board showed up today. Almost done populating it. I have a few areas to clean up. A good soldering station would have made this even easier.
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POST PICTURES FAGGOT
I mean, ah, pretty please? ;)
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Pics of the populated board. One complaint is the size, rather lack thereof, of the solder pads. I understand that they need to be as small as possible to keep the board dense, thus smaller, but it kind of makes soldering a bit tricky. A true pencil type soldering iron would have made assembly easier for me, but it came out alright. Looks there are a couple of joints that could be reworked. :mexi:
(https://realhomemadeturbo.com/forum/proxy.php?request=http%3A%2F%2Fimg10.imageshack.us%2Fimg10%2F484%2Fjbperfphdriverboard003.jpg&hash=71a343ecb9a60adb15094417f0cbb06ba8eb9e10)
(https://realhomemadeturbo.com/forum/proxy.php?request=http%3A%2F%2Fimg10.imageshack.us%2Fimg10%2F931%2Fjbperfphdriverboard002.jpg&hash=6d253ddfdd1b57a831dfcc158b1fc484d4781573)
I need to pick up another P06 as a test mule since I plan to integrate the P&H board into the ECU rather than having another box outside of the ECU.
I'd really love to get a demon and an Ectune license as well.
:noel:
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Looks good.
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What is the purpose of the driver exactly?
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What is the purpose of the driver exactly?
To drive peak and hold injectors the way they were originally intended to be driven. (sounds kind of redundant)
Peak and hold injectors are supposed to be fed a high current at the beginning of the opening event to slam the pintle open( this helps with larger heavier pintles) and then drops the current to a lower level to keep them open for the duration of the opening event.
This adds a greater degree of precision to low Z, injectors to allow them to open consistently at low pulse widths.
I am sure JD will chime in to correct me.
:P
Granted, DSM 450s are relatively small injectors, but I figured I would give it a try and possibly have a good driver for larger injectors in the future.
And yes I know of the high Z 1000 cc/min injectors that are supposed to have great atomization characteristics as well as stability at low pulse widths.
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Good thing to know. Thanks guys!
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Been slacking on this project. Will try to get the board at least tested for basic functionality this week.
I would kind of like to setup a scope to check out the output waveform as well. I may see it I can get something done in that area as well since we have some decent scopes in the Physics lab at school. I don't recall if they have a signal generator built in or not. I know we have some of those as well, but I dunno if they are up to the task for use as an input. Gonna have to dig up a 12V power supply that has more than a 100 mV capacity as well. Bah.