MAF help please

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MAF help please

Postby AJJ73 » Fri Dec 22, 2017 11:13 am

I am having an issue when attempting to start and run in MAF mode. The ECU reads the MAF (I can tell by blowing through it) just fine when the ECU is on and the engine is not running. The moment, the engine tries to start, the ECU stops reading the MAF and continues to not read the MAF until the engine dies and fuel pump relay shuts off.

Im using a MAF that I have flow calibrated and worked just fine on another engine with MicroSq. Everything is wired and grounded properly (I have checked this many times). Settings in tunerstudio are all set to MAF where we required, and voltage/flow table is properly entered.

I have never encountered this before, and this ECU worked properly on the last motor I put together. Do you have any suggestions as to what I may have wrong? I have attached a tune and log file showing data from my attempts to start yesterday. The timing is fixed and I have verified all other operational parameters. Am I missing something basic? I am not running any sort of idle valve. The MSQ and data log are attached.
Attachments
2017-12-21_20.05.21.msl
Start attempts with MAF- no signal
(1.15 MiB) Downloaded 9 times
MAF 12-21.msq
Current MAF tune
(119.54 KiB) Downloaded 11 times
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Re: MAF help please

Postby Blown88GT » Sat Dec 23, 2017 11:29 am

Something wrong with your toothed wheel pickup.
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: MAF help please

Postby AJJ73 » Sat Dec 23, 2017 9:17 pm

Blown88GT wrote:Something wrong with your toothed wheel pickup.


Thank you very much for responding. Now please forgive my ignorance when I ask- what tells you that? The engine runs in Speed Density. Shouldn't the engine not run in SD or MAF with a toothed wheel issue?

The attached is the engine running in SD. The MAF signal goes flat line (displaying constant last value) the moment the fp relay turns on. Starts to register again the moment it shuts off. The Ford maf is currently powered from ECU relay, so this shouldn't turn it of. Engine is a VW 4 cyl 2.0L 8v , w/truck coils, distributor polled for seq.

I have done the following to date:
Verified power to MAF, double checked grounds,
checked output signal of MAF while with multimeter with engine run in SD,- multimeter registers voltage changing, ECU does not, neither does data log.
disconnected harness from ECU and verifed voltage changing at MAF input pin on harness, while cranking. Not a wiring problem
checked the crank and cam wheels. Attached is a composite log.
Verfied TDC and cam/ign phase. - although, it is an open window on a hall distributor and manual says, it says it should have "low" poll level, only the "high" poll level worked correctly.
I also tried a different microsquirt unit, with the same results. This leads me to believe that I have a wiring issue. However, I am getting reasonable readings on the multimeter at the ms harness. So that kinda rules out a wiring issue, doesn't it?

I am doing something wrong in TS to cause the ms not to read the MAF?

Thank you to anyone who can point me somewhere!
Attachments
VW SD maf enabed.msq
(119.14 KiB) Downloaded 5 times
IGN LOG 2017-12-23_21.38.28.csv
(78.02 KiB) Downloaded 2 times
SD 2 Start 2017-12-23_20.54.27.msl
(505.45 KiB) Downloaded 3 times
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Re: MAF help please

Postby Blown88GT » Sun Dec 24, 2017 1:53 pm

Not many use MAF, I'm one of the few. I didn't notice any settings is TS that looked wrong.
I want to verify that you have a Microsquirt & not a Microsquirt Module?
Pin5 - SPARE ADC2
Pin29 - SPARE ADC

You have SPAREADC2 ENABLED which indicates you are using Pin5.
Won't display image from http://www.useasydocs.com/
Image
Last edited by Blown88GT on Sun Dec 24, 2017 5:12 pm, edited 1 time in total.
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: MAF help please

Postby AJJ73 » Sun Dec 24, 2017 2:34 pm

Thank you very much for any help you can offer. I can usually solve my own problems, but this has me stumped.

I have pin 5 enabled (spareadc2) as maf at the moment. Using microsquirt v3.57.
I was thinking if trying to connect it to spareadc 1 to see if anything changes. The weird part is that the thing reads until I try to start.
Merry Christmas!
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Re: MAF help please

Postby Blown88GT » Sun Dec 24, 2017 5:33 pm

2017-12-24_193008.jpg
2017-12-24_193008.jpg (103.16 KiB) Viewed 217 times
Is it possible you are using the wrong ground pin for the MAF Signal?
12V Ground & MAF Signal Return are not the same

You said you had a Ford MAF, but don't know which one or how many pins or pinout.
If your Ford MAF has 4 pins:
12V Power - Pin 1
12V Ground - Pin 22, 23
MAF Signal - Pin 5
MAF Signal Return - Pin 20

Sensor grounds (Ampseal pin 20 and 18, if populated) - the coolant sensor, intake air temperature sensor, throttle position sensor, and external MAP sensor needs to be grounded back to pin 20 on the AMPSEAL. This is the low-current sensor return path and it needs to be kept away from the high power ground. This wire hooks directly to the sensors only and not to the engine block - it is its own return path.

Your tune still has Primary Fuel Load as Speed Density. Didn't notice it before.
Change this to MAF.
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: MAF help please

Postby AJJ73 » Mon Dec 25, 2017 7:35 pm

Hi- thank you again for your help. I am using the diyautotune pre-made harness and v.357micro squirt

You saw that I was running in Speed density in the second msq that I posted. That was because I was intentionally running in SD to see if I could get a maf signal to record in Tunerstudio. The first msq i posted I was running in MAF mode.

I have a 6 wire ford maf, purchased maf and pigtail from P-MAS and wired as shown in the photo below (based on Hardware manual and internet references)- the wiring is from left to right-
1-12V-red wire- this is powered ad stays powered wihen ECU is powered- tested and confirmed.
2-PWR Gnd- this is grounded to the same stud on the engine block as the coil pwr gns, and the ms gnd (pin 22,23)
3- MAF sensor Gnd- this is grounded to same sensor ground (pin 18,20-the harness came with 2 sensor gnd leads) (in a metripack bus sealed bus bar) as the map, tps, iat, and coil logic gnd- see photo below. TPS, IAT, Coil logic, map all function properly.
4- MAF signal- pin 5 (Spareadc2)
5 IAT sensor gnd
6 iat signal

Webp.net-resizeimage (2).jpg
Webp.net-resizeimage (2).jpg (88.19 KiB) Viewed 197 times


The sensor grounds are properly isolated from the power grounds. Photo below shows some of the sensor gnds. All other sensors are working properly. Power ground stud on engine block has ms pwr gnds (22, 23), Coil pwr gnd, WBO2 (Mtx-l) gnd and MAF pwr gnd) Photo below shows how sensors are isolated from pwr grounds.

Webp.net-resizeimage (3).jpg
Webp.net-resizeimage (3).jpg (587.32 KiB) Viewed 197 times


I have also checked the polarity of the maf signal output voltage with my oscilloscope and a voltmeter (between sens gnd and spareadc2. The signal at pin 5 while the engine is running in SpeedDensity is positive and registers on the scope as about what would be expected for voltage. (I pulled the pin out of the ampseal to test it).

I have checked the sensor and power ground connections and all other connections for that matter, over and over again, I can't think of another diagnostic test to do at this point. I am thinking about maybe rerouting the maf through Spareadc1, but, if the port was the issue it should have worked when I plugged it into a different microsquirt. What am I missing? Iwas thinking that maybe the second sensor ground on the harness wasn't really a sensor ground, but if that was the case, the tps and map wouldn't work.
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Re: MAF help please

Postby Blown88GT » Tue Dec 26, 2017 2:45 pm

I'm not sure if MAF will record if you don't enable it in TS.

You referred to the "second sensor ground"??
All sensor grounds connect to pin-20. It looks like pin-18 may not be connected or shouldn't be used.
The Microsquirt Module which is similar has only 1 sensor ground pin. Pinout is completely different.
http://www.microsquirtmodule.com/
Attachments
ew3_hires.gif
ew3_hires.gif (81.14 KiB) Viewed 174 times
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: MAF help please

Postby AJJ73 » Wed Dec 27, 2017 9:42 am

Hi- I think the DIYautotune harness has two leads coming off pin 18. To doublecheck, I hooked up all sensors to the pin 18 white/black sensor gnd wire and nothing changed from a MAF operation standpoint. As soon as the FP relay kicks on, MAF readings flat line at a fixed low flow value. I have an email out to Matt Cramer verifying that both of those white/black strip wires are sensor grounds. I have used this harness on other installs and never had an issue using both white/black wires for sensor grounds.

Because it seems I have some sort of issue with FP relay turning on and losing readings. I removed the two relays attachd to ECU FP relay ground (pin 8). These two relays power fuel pump, coils, and injectors. When I remove those relays and crank, the MAF does the same thing it always does. Reads until engine cranks enough to trigger the fp relay gnd.

Is it possible there is a logic problem some where?
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Re: MAF help please

Postby rickb794 » Wed Dec 27, 2017 1:29 pm

if you have checked that both power and ground are unaffected,

i would reload the firmware and double check which hardware is selected.
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Re: MAF help please

Postby Blown88GT » Wed Dec 27, 2017 2:44 pm

It sounds like the cable harness is not what you expected.
Ohm it out yourself. Why wait for a reply which could be wrong.
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: MAF help please

Postby AJJ73 » Wed Dec 27, 2017 3:36 pm

rickb794 wrote:if you have checked that both power and ground are unaffected,

i would reload the firmware and double check which hardware is selected.


I just verified proper power ground everywhere, wire by wire. Sensor grounds have also been verified and reverified. I have also installed the firmware at least 3 different times on two different microsquirt ECU's. I wish these were the issue!

I have great MAF output signal at pin 5 during engine running in Speed density. The problem is that the code doesn't appear to read or consider it when the engine is running or cranking. I am wondering if there is logic problem in ECU.
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Re: MAF help please

Postby AJJ73 » Wed Dec 27, 2017 3:43 pm

Blown88GT wrote:It sounds like the cable harness is not what you expected.
Ohm it out yourself. Why wait for a reply which could be wrong.


I double checked the harness with my multimeter and both wires are sensor grounds. Diyautotune also got back to me and confirmed that I was correct in that both wires are, indeed, sensor grounds. So this aspect is correct. Are you running a MAF sensor and a MAP sensor? I wonder if this is where I am running into a problem- see below:

I was told by my MAF supplier that I need to output the MAF signal to MAP sensor input wire (pin 24) for a MAF install. I may try this just to prove to myself that my wiring is ok (which I am really starting to believe it is). However, I would like to run my coils using speed density, as all of my ignition maps are based on SD loads. TS allows you to run MAF/MAP blend, so I can't imagine that the Spareadc2 input (pin 5) wouldn't work. TS says pin5 is enabled and functioning- it just doesn't register a signal internally when the engine is running#@$!!
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Re: MAF help please

Postby jsmcortina » Wed Dec 27, 2017 5:01 pm

In your datalog I see "ADC7" which is the raw value of SPAREADC2, do the values there match up with what you are expecting from the MAF. (The scale is 0-1023 for 0-5V.)

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Re: MAF help please

Postby Blown88GT » Wed Dec 27, 2017 5:36 pm

AJJ73 wrote:...
1. I double checked the harness with my multimeter and both wires are sensor grounds.
2. Diyautotune also got back to me and confirmed that I was correct in that both wires are, indeed, sensor grounds. So this aspect is correct. 3. Are you running a MAF sensor and a MAP sensor?
4. I wonder if this is where I am running into a problem- see below:
5. I was told by my MAF supplier that I need to output the MAF signal to MAP sensor input wire (pin 24) for a MAF install.

I may try this just to prove to myself that my wiring is ok (which I am really starting to believe it is). However, I would like to run my coils using speed density, as all of my ignition maps are based on SD loads. TS allows you to run MAF/MAP blend, so I can't imagine that the Spareadc2 input (pin 5) wouldn't work. TS says pin5 is enabled and functioning- it just doesn't register a signal internally when the engine is running#@$!!

1. I mean buzz every single wire in that harness, not just the sensor grounds.
2. What about all the rest of them & the colors?
3. Yes.
4. No.
5. I believe he told you that but he doesn't know what he's talking about.

I'm looking at all 35 pins here: http://www.microsquirt.info/uswiring.htm
This proves 3,4 & 5 above.
Pin5 Spare Input This is a second spare ADC(ADC7). It is used for alternate MAF pin or knock sensing, but it can be used to record whatever 0-5 Volt signal is put on it if neither the MAF option nor the knock option uses it. In this case it is stored in outpc.knock.
n/a indicates the harness wire can be any color.
Pin29 SPARE ADC Can be used for external baro MAP sensor. Orange/Green

There is something wrong in your wiring if the FP relay has any affect on the MAF signal.
You stated the clue here:
Because it seems I have some sort of issue with FP relay turning on and losing readings. I removed the two relays attachd to ECU FP relay ground (pin 8). These two relays power fuel pump, coils, and injectors. When I remove those relays and crank, the MAF does the same thing it always does. Reads until engine cranks enough to trigger the fp relay gnd.
If you removed the relays & it's still doing it, the problem is in the wiring.

Print out the drawing, check every wire & highlight them as you go. It might take all day, but you'll find it.
All the issues seem to be centered around the middle of the first 2 rows of the Ampseal connector.
I trying to think how would it be wired to function the way it is.
If you can see that, you'll find the error immediately.
I'm going to speculate pin-8 & pin-18 are reversed.
Is the Purple Wire on the 1st row, pin-8?
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: MAF help please

Postby jsmcortina » Wed Dec 27, 2017 5:44 pm

The text you are quoting there is for MS2/BG, it mostly doesn't apply to MS2/Extra.

James
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Re: MAF help please

Postby AJJ73 » Wed Dec 27, 2017 10:34 pm

jsmcortina wrote:In your datalog I see "ADC7" which is the raw value of SPAREADC2, do the values there match up with what you are expecting from the MAF. (The scale is 0-1023 for 0-5V.)

James

The ADC values in ADC7 correspond to a reasonable voltage/flow value at say 1800 rpm and high vacuum. It is showing about 200 AD counts which is around 1V ~ 40 g/s.

Tonight, I connected the MAF output lead (from pin5) to the MAF input (pin24). I switched settings in TS to reflect those changes. I then attempted to start the engine. Nothing changed. Multimeter still shows that I am getting a signal between sensor gnd under the hood and input into ecu. MAf still reads before fuel pump relay engages. The only other issue I am having is the WBO2 is registering about .3 off and it is powered from the same relay as the ECU and grounded with the ECU.
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Re: MAF help please

Postby Matt Cramer » Thu Dec 28, 2017 7:42 am

What happens if you try using the other Spare ADC channel? MicroSquirts tied ADC7 to PT7 as well; this was planned for supporting frequency based MAFs. ADC6 is not tied to anything separate. This would rule out if something is commanding PT7 to be pulled down.
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Re: MAF help please

Postby AJJ73 » Thu Dec 28, 2017 1:31 pm

Blown88GT wrote:...

There is something wrong in your wiring if the FP relay has any affect on the MAF signal.
You stated the clue here:
Because it seems I have some sort of issue with FP relay turning on and losing readings. I removed the two relays attachd to ECU FP relay ground (pin 8). These two relays power fuel pump, coils, and injectors. When I remove those relays and crank, the MAF does the same thing it always does. Reads until engine cranks enough to trigger the fp relay gnd.
If you removed the relays & it's still doing it, the problem is in the wiring.

Print out the drawing, check every wire & highlight them as you go. It might take all day, but you'll find it.
All the issues seem to be centered around the middle of the first 2 rows of the Ampseal connector.
I trying to think how would it be wired to function the way it is.
If you can see that, you'll find the error immediately.
I'm going to speculate pin-8 & pin-18 are reversed.
Is the Purple Wire on the 1st row, pin-8?
[/quote]

I definitely don't have those pins crossed. Fuel pump relay output (pin8) is connected to 2 relays- 1 just fuel pump, and 2 for injectors and ignition. The fact that it rejects the signal when it cranks almost makes me think its a logic issue.

My first thought was there was something wrong with the wiring due to the fuel pump issue. I am still convinced it could be the issue. Especially since I seem to have an issue with the Wideband not reading consistent with the gauge despite the fact that it and the ECU are powered and grounded at the same places. However, as JSMCortina pointed out, I am getting ADC counts on the input pin that are reasonable and change with rpm- (actually the counts reflect about 15grams/sec at high vacuum and 1800rpm, read my spreadsheet wrong last night). But those counts aren't registering into grams/sec or MAF volts internally.

I am going to try your suggestion and check every wire right after I connect the MAF output to Spareadc1 as suggested by Matt Cramer.

More results to follow.. thank you everyone for your assistance, suggestions welcomed.
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