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MarcelB

Lean Out issue

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I have had the sam issues with staging also.. I fought is so much and I started using aux injection instead and have had much better results as it does not pull fuel away from the primarys.. I run my primarys on q16, and my 2300cc secondarys run on methanol, this setup has been a dream and easy to tune... Just a idea for you to try..

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So we suspected that there was an issue with the injector voltage supply , maybe something was causing it to attenuate so I did all the voltage and continuity tests and put in a relay which supplies power directly from the battery just to be sure .............. NO CHANGE :x problem still exists :!: :cry:

Moved the ECU power from the power distribution system to the battery through a relay (same which now supplys the injectors) , the afr's are better (13+ to 14+) but still not good , I've had to open increase the injector pulse widths from 22-25 ms to 38-45ms!! so now I'm thinking it could be a fuel delivery issue!! At present I have the fuel rails set up in a series configuration with gas flowing from the secondary rail to the primary rail , i'm going to sepsrate them and run them in parallel to see what happens.

Are you able to get a PC log as it leans out and what would be really good is a scope image of the injector drives.

I can't get a log now because it starts up and runs for about 3 seconds then stalls and no I don't have a scope but I will see if I can get one but what really confuses me is that it started up an ran fine on both sets of (brand new) injectors , so why would they be causing a problem now??

I have had the sam issues with staging also.. I fought is so much and I started using aux injection instead and have had much better results as it does not pull fuel away from the primarys.. I run my primarys on q16, and my 2300cc secondarys run on methanol, this setup has been a dream and easy to tune... Just a idea for you to try..

It is not a stsging issue , I cant even get it to start and when it does it idles for about 5 minutes then it leans out and stalls.

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All signals like MAP TPS etc are on the money at key on?

Engine RPM is correct, no anti theft turned on on the ECU or ecu hold power active.

Yes , yes and yes , I haven't even connected any of the digital inputs except for the engine start position. Today I disassembled the fuel system I order to run separate feeds to each rail , I found the braided hose which connected the rails was kinked !!!! since the gas flowed from the secondary to the primary rail ,I am hoping this kink was restricting flowand causing the problem,i'll post again when I am done.

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Yes , yes and yes , I haven't even connected any of the digital inputs except for the engine start position. Today I disassembled the fuel system I order to run separate feeds to each rail , I found the braided hose which connected the rails was kinked !!!! since the gas flowed from the secondary to the primary rail ,I am hoping this kink was restricting flowand causing the problem,i'll post again when I am done.

:( Nope !! wasn't that !!! I did get it to start but it wouldnt idle, afr's were around 15.5 :1 and the values in the map were in the high 40's !!! So to ensure the fuel system wasn't at fault I went ahead and pulled all the filters in the system all were clean except for the first one located immediately on the discharge of the pumps , it was 100% plugged ! I could've filled it up with water like a beer glass, I was actually happy to find this since it would've properly explained all the symptoms I am getting , so I cleaned it up replaced it and ........NOTHING ! same S@#%T different day , at this point I do not know what to check again , maybe its time to send it back to you guys to check and repair :?: please advise.

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Hi Marcel,

do you have any filters inline after the one that was blocked.

I see you stated that you cleaned all of your filters.

If there are no filters after the one that was blocked, is there a possibility that some material has entered the new injectors and blocked the filter baskets.

Have you done a fuel pump flow test.

Do your sparkplugs indicate that the engine is definitely lean ?

Looking at your PCL file, you have your master fuel at 20 MS, with an extra trim of 5%.

What is your static fuel pressure ?

With such large injectors and a load value of 40 at idle on a small displacement engine, one would imagine that your AFR would be very rich.

However if the sparkplugs are fouled or wet the AFR can read lean due to higher amounts of unburnt oxygen in the exhaust.

How is the compression on the engine, a damaged or worn apex seal can cause lean mixture readings also.

I am just throwing you a few extra thoughts here, diagnosing issues such as you have are very complex without the vehicle in front of you for testing.

You may have done these tests and checks already, but I have not read anything indicating you have, so I thought I would mention them.

Regards

Dave.

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Marcel,

one more thing for you to do.

If you can get the engine to start again, have the laptop close by, with the engine running can you hit F2 and save the file as Marcel running values and post the PCL file please.

Even better still if you can manage to do a data log.

Would be handy to see some running values.

Thanks

Regards

Dave.

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Hi Marcel,

do you have any filters inline after the one that was blocked.

I see you stated that you cleaned all of your filters.

If there are no filters after the one that was blocked, is there a possibility that some material has entered the new injectors and blocked the filter baskets.

Have you done a fuel pump flow test.

Yes I have another filter in line located in the engine bay , an AEROMOTIVE filter with a 100 micron element,I do not think the filter baskets are blocked because the 100 micron filter was very clean , the previous set of (new ) inlectors were clen when I removed them and now the second set of (new) injectors are behaving the exact same way.

Have you done a fuel pump flow test.

Yes I did a simple flow test however I did not quantify exactly how much fuel was flowing but it was avery healthy flow ,also when I am doing the checks the fuel pressure remains where it is set which is at 43psi without a flicker of the needle. I suspected that the pressure might be good but that the flow was being blocked somehow , this is why I went through the system ,found and changed a kinked hose and changed the fuel supply configuration to the rails from series to parallel.

Do your sparkplugs indicate that the engine is definitely lean ?

No I did not pull the plugs , I figured that they will tell me the same thing the wideband and motor behavior is saying to me plus its a lot of work :oops:

Looking at your PCL file, you have your master fuel at 20 MS, with an extra trim of 5%.

What is your static fuel pressure ?

Static pressure is 43psi

With such large injectors and a load value of 40 at idle on a small displacement engine, one would imagine that your AFR would be very rich.

Yes normally it would be half that !

However if the sparkplugs are fouled or wet the AFR can read lean due to higher amounts of unburnt oxygen in the exhaust.

Nope I do not think they are fouled , if they were the motor would never kick.

Hi Marcel,

How is the compression on the engine, a damaged or worn apex seal can cause lean mixture readings also.

The compression is great! Its a brand new motor which hasn't been run yet!

I am just throwing you a few extra thoughts here, diagnosing issues such as you have are very complex without the vehicle in front of you for testing.

You may have done these tests and checks already, but I have not read anything indicating you have, so I thought I would mention them.

Regards

Thanks for taking the time to respond !

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Hi Marcel,

I would check the sparkplugs.

Even if they are hard to get at, the sparkplugs are your window to what is really happening in the combustion process.

I have had engines running on fouled plugs, carbon fouling can create ground tracking paths to the inside of the sparkplug base itself.

The spark travels the easiest path to ground, there is sometimes enough spark to get partial fuel mixture combustion.

However the flame (burn) propagation is not complete, I refer to this a lazy burn.

The air fuel mixture is not completely ignited.

I do not have much experience with rotary engines,

However around 6 months ago I was called to help a guy I know with his 13REW with a big turbo and all the fruit.

He had built a new engine and had done extensive porting to it.

He was running a V44 based PNP.

He couldn't get the engine to run properly and achieve a realistic air fuel ratio.

Engine would start and run, not very well but would run.

We checked the ignition timing etc and all was good.

I tried adjusting his idle load fuel values and they made very little if any change to the mixtures.

I asked him what plugs he was using, brand new ones was the reply.

I asked if I could have a look at them.

He battled with the cramped conditions and removed the plugs.

The 2 leading plugs were heavily carbon fouled and the trailing plugs were wet.

He realised he had the incorrect types of plugs fitted to the leading and trailing.

He took out some new sparkplugs and showed me.

You rotor guys sure use strange sparkplugs, he fitted the new plugs and the engine fired and idled with the radical, blap,blap note that I expected with this type of build.

I now had control of the idle mixtures.

Later he decided to do some street tuning by himself with data logging.

I spoke to him a couple of weeks later and asked him how he went.

He said he didn't get far as the engine kept running lean and not running very well.

He did a compression test and found one of his new expensive apex seals had failed.

I can't remember what these seals were made from, but they were supposed to be the latest and greatest.

In this instance the owner was hit with a double whammy.

As for the sparkplug issue, I have been on the receiving end of the dreaded sparkplug fouling issue on quite a few occasions.

I find that Irridium and Platinum tip (thin centre electrode) type plugs to be the worst for this.

Don't get me wrong, these types of plugs are fine when exposed to realistic air/fuel mixtures, but tip a bit more fuel in and they soon show there true colors.

Now I know you don't have these types of plugs in your engine, but rotary engine plugs are even weirder.

Like I said above the sparkplug is your WINDOW to the combustion process.

Take a look, if in any doubt.

Regards

Dave.

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sounds like sound advice from dave there.

can you go through the exact symptoms once more?

eg.

"the engine starts normally, then starts to lean out and no adjustment seems to fix this?"

how is your fuel tank ventilation handled? can you give a complete description on the fuel system,

any catch tanks, what pumps, what filters, what material is the hoses, what is the fuel used, ect ..

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Just a question, what is your fuel pump? How many liters per hour? How many liters per hour is your injectors at 100%? Do you have enough fuel pump to run injectors like this? I would think you would at least need 2 magnafuel 625 to even come close to fueling this thing..??? Also, wht size is your fuel line for the amout of volume this thing will drink, you should have I would think -10 at the minimum and a -12 fuel rail to hold the volume at the head of the injectors...

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Sounds like a very frustrating problem. It´s a little bit stupid question, but after you discovered the kink at the fuel line and the blocked filter, did you put your tune back to the state where it was before the problems started and you are not flooding the engine with huge amount of fuel?

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Just a question, what is your fuel pump? How many liters per hour? How many liters per hour is your injectors at 100%? Do you have enough fuel pump to run injectors like this? I would think you would at least need 2 magnafuel 625 to even come close to fueling this thing..??? Also, wht size is your fuel line for the amout of volume this thing will drink, you should have I would think -10 at the minimum and a -12 fuel rail to hold the volume at the head of the injectors...

The pumps are twin BOSCH 044's the fuel feed line is -10AN fuel rails are -10AN also , fuel pressure regulator is an Aeromotive PRO ,and fuel return is -8AN.

Sounds like a very frustrating problem. It´s a little bit stupid question, but after you discovered the kink at the fuel line and the blocked filter, did you put your tune back to the state where it was before the problems started and you are not flooding the engine with huge amount of fuel?

Yes , it definately is :!: :oops: .....nope not a stupid question ! I did normalized the map and set the pulswidths back to where they were (the low 20s ) when the car was behaving itself. I am now making arrangements with my dealer to get another V88 to try out in the car to verify the "set-up" in the car is good, if it works without problem then it will indicate that the ECU is at fault (as I suspect) .

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So my dealer came over with a vehicle running another V88 , we swapped them out reloded maps and the 88 out of my car had the other vehicle (SUBARU) idleing smoothly whilst mine was doing the same thing :( :evil: One thing we noticed though , whilst starting and looking at the FUEL MAIN screen a pad lock appeared next to all of the parameters in the menu , once it started up they all disappeared except the one next to INJECTION MODE parameter , shortly after the motor is cut ! seems like the software is cutting the engine for some unknown reason . Since both ECUs are doing the same thing I have ruled them out along with any electrical issue , I intend to find my previous laptop which would have my last configuration (which I used to start up another rotary a month ago) install it an see what happens.

post-1148-143450214613_thumb.png

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that map limit seems a bit low to me, did you check from the logs that its not hitting any limits? are the limits configured as fuel cut?

i had an issue in the dyno where from the MAP logs it looks like i'm not hitting the limit, but since the log is slower than what is actually

seen by the ECU the map limit status went up and it started cutting the ign.

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that map limit seems a bit low to me, did you check from the logs that its not hitting any limits? are the limits configured as fuel cut?

i had an issue in the dyno where from the MAP logs it looks like i'm not hitting the limit, but since the log is slower than what is actually

seen by the ECU the map limit status went up and it started cutting the ign.

Yep , experienced this during first start up so ive since turned it completely off.

post-1148-143450214646_thumb.png

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Hi Marcel,

can you open your PCL file,

Go to the file tab, top left of page, go to SAVE AS,

Create a new file called MARCEL RUNTIME DATA.

Make sure that the top of your screen now has MARCEL RUNTIME DATA in the PCL file name.

Connect to your ECU, while ONLINE hit F4 so the new PCL file is loaded to the ECU.

Everything will be the same, just the PCL file name will be different.

Start the engine and encourage it to run if possible, if possible get the engine to running temperature.

WHILE THE ENGINE IS RUNNING, hit F2 and this will save the engine running data in RUNTIME VALUES to the new PCL FILE.

Post the MARCEL RUNTIME DATA PCL file on this forum.

This way we can check as much live running data as possible.

When you go OFFLINE to the ECU and EXIT VTS, when the software prompt comes up saying do you wish to save before exit, click no or the PCL file with the running values will be over written.

My only other suggestion is if you have TEAM VIEWER on your laptop with internet access while connected to your ECU, I could log in and see if I can see anything LIVE.

Regards

Dave.

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One thing we noticed though , whilst starting and looking at the FUEL MAIN screen a pad lock appeared next to all of the parameters in the menu , once it started up they all disappeared except the one next to INJECTION MODE parameter , shortly after the motor is cut ! seems like the software is cutting the engine for some unknown reason.

Hi Marcel,

The injection mode is locked once the engine is seeing RPM, this is a safety thing, engine damage could be caused if the injection mode was changed while the engine were running.

Normally if the engine is applying any sort of ignition or fuel cut it will show in the runtime value window. The only way you are going to be able to truly tell is by examining the injection and ignition outputs on a scope. I know you said you do not have one, or access to one, but it may be worth spending the money to pay someone for half an hour to see what is happening.

Scott

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Hi Marcel,

The injection mode is locked once the engine is seeing RPM, this is a safety thing, engine damage could be caused if the injection mode was changed while the engine were running.

Normally if the engine is applying any sort of ignition or fuel cut it will show in the runtime value window. The only way you are going to be able to truly tell is by examining the injection and ignition outputs on a scope. I know you said you do not have one, or access to one, but it may be worth spending the money to pay someone for half an hour to see what is happening.

Scott

I would if I can find someone to pay ! since the ECU we interchanged exhibited the same behavior , would it be possible for you to put my map in another 88 , connect it to your emulator and see what it does ? this way I can then narrow it down some more to maybe the car itself.

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Hi Marcel,

Apologies in the delay of testing your base-map. This afternoon I put it into my engine simulator and inspected the injector drives on a scope.

Here is a screenshot of me logging it:

post-1076-143450214648_thumb.png

As you can see in the image, the primary injection is working well and there is no secondary injection as the conditions for this have not been met (>3500 RPM)

The ignition angle also appears in a normal range.

If you could do a PCLog with all parameters, of you trying to start the engine it could be useful.

Cheers,

Scott

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The pumps are twin BOSCH 044's the fuel feed line is -10AN fuel rails are -10AN also , fuel pressure regulator is an Aeromotive PRO ,and fuel return is -8AN.

Yes , it definately is :!: :oops: .....nope not a stupid question ! I did normalized the map and set the pulswidths back to where they were (the low 20s ) when the car was behaving itself. I am now making arrangements with my dealer to get another V88 to try out in the car to verify the "set-up" in the car is good, if it works without problem then it will indicate that the ECU is at fault (as I suspect) .

it still sounds like the fuel pumps are not big enough!! Does each pump have its own dedicated pickup? How do the pumps mate the high pressure together?

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Turns out this was not the problem ! Still haven't fixed it yet , the ECU was tried on three different cars where it worked perfectly , will be looking at completely re-wiring with a pair of brand new harnesses.

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