Raceghost

iTrader: (4)

Hi everyone. It's me with another crazy issue with multiple symptoms.

Even after the 76 Degree C Thermostat, car boosted and AFR's were in check.

Recently I change my spark plugs. I was running the Denso IW24's gapped at .20 for 30Lbs of boost on pump Idaho 91.

I changed them to the stock EVO 8 plugs NGK IGR7A-G gapped at .24, ran 30lbs with no issue earlier in the spring.

The only reason I changed them, is for tuning purposes since i have been doing extensive fuel tuning. It was suggested by another tuner to run the copper or stock plugs since Iridiums are $10 per.

But here's what's up...

Issue 1) No change in tune, and now AFR's are almost .75 off. SHould be in the low 11's, but now running 11.9 to 12.0. No Boost leaks. No other changes to car.

Weather in Idaho has changed from the 40~50 degrees F / 4 to 6 degrees C to freezing/snow. The last couple of evenings when I have gone out trying to figure a few things out, it has been 0-2 degrees C, and approx 30 degrees F. I read some where on here, that tuning in colder weather is better, because of lean/rich vs cold/warm. Things richen up in warmer weather.

Like I said, reloaded last known good rom with 11.2 AFR's up top, no dice, still lean.

Issue 2) Since I was doing fuel tuning, both open loop and closed loop tuning for best cruise mpg, I decided I should reset the trims. Unfortunately, I accidently left the car ignition in accessory mode, when I pulled the 20 Amp fuse in the box under the hood, that we all know resets trims. Then plugged it back in in the same mode. Ever since then, trims no work, no matter what. I have checked all switches in rom, as well as verified I have 02/STFT feedback, which I do, just no trims. Reset with car off, and no dice. Reloaded rom with closed loop enabled, no dice. Put 150 miles on car, still no Trims, or learning parameters. I have checked all fuses related to fuel circuit, even run the actuators in EVOScan for the fuel pump and fuel solenoid, both work, fuel pump kicks in to high mode, also verified in logs with fuel pump switch.

I'll post more symptoms as I find them. Working late tonight to troubleshoot.

EDIT:
Found a few things of concern. First, the wastegate pin holding the lever to the actual wastegate on the turbo was missing. Fixed.

Map sensor was covered in oil. Cleaned and fixed, ill get to cause in a moment.

Cleaned temp sensor on thermostat housing, was pretty dirty. Read that if it is not reading right, it can cause open/closed loop issues.

Double checked all boost related hoses for holes/leaks/loose clamps, etc. Good to go.

I unhooked the battery from both terminals and let it sit for about 30 minutes. Then I touched both leads together to make sure all juice was out of the system. I pulled the trim fuse as well. Then reconnected. My thinking was to reset the system fully, in effort to get those trims to respond now.

Found this little issue: Oil all over the backside of the motor, on the MAP sensor, Fuel Relays, Fuel Pressure Solenoid, etc. Took me a bit, but cleaned everything I could get to, and topped of the missing quart of oil. It was tough, but pushed the check valve back into place. Any suggestions on making sure it doesn't come out again? Side note, I have a breather valve on the other end of the valve cover going to a catch can. I still must have a lot of crankcase pressure to push the check valve out of the valve cover... Any thoughts?




Went through my tune and found an anomaly. I didn't change this temperature when changing out my thermostat, and have a sneaky suspicion, that this is the culprit. "Fuel Pump Hi-Speed Mode, Water Temp Switches" I was playing around with these prior to my thermostat goin out, and never noticed. I assumed these tables were for overheating affect, to cool the motor. But after looking through the code, and finding that the stock ROM was set to the 82 degrees C just like all the other temp scaling, I assume it controls the fuel pump and allows it to go high pressure mode. Someone can correct me if I am wrong. Maybe some of the disassemblers can chime in and tell me what exactly these switches do. I know what the Rising Load threshold does, but all the other ones I have just guessed on. I remember MFRED saying the Load Hysteria needs to stay the same at 5.0. Either way, we will see here after while when I can start it. Neighbors get a little upset when I fire this thing up at 4 A.M. LOL.

Here is the 94170715 tables and defs:
<table name="Fuel Pump Hi-Speed Mode, Rising Load Threshold" category="FUEL PUMP CONTROL" address="4556" type="2D" scaling="Load8">
<table name="ENGINE" address="635a" type="Y Axis" elements="10" scaling="RPM"/>
</table>

<table name="Fuel Pump Force Hi-Speed Mode, Startup Timers" category="FUEL PUMP CONTROL" address="19d2" type="2D" scaling="FP_TIME">
<table name="Startup Conditions" type="Static Y Axis" elements="3">
<data>19D2 Force Hi-Speed mode After Startup, Water Temp exceeds W2 and Air Temp exceeds A2 XPUMPTM</data>
<data>19D4 Force Hi-Speed mode After Startup, Water Temp exceeds W1 and Air Temp exceeds A1 XPUMPTM2</data>
<data>19D6 Force Hi-Speed mode After Startup, Water Temp below W1 XPUMPTM3</data>
</table>
</table>

<table name="Fuel Pump Force Hi-Speed Mode, Unknown Timers" category="FUEL PUMP CONTROL" address="19d8" type="2D" scaling="FP_TIME">
<table name="Startup Conditions" type="Static Y Axis" elements="3">
<data>19D8 Force Hi-Speed mode, Water Temp exceeds W2 and Air Temp exceeds A2 XFPUTM</data>
<data>19DA Force Hi-Speed mode, Water Temp exceeds W1 and Air Temp exceeds A1 XFPUTM2</data>
<data>19DC Force Hi-Speed mode, Water Temp below W1 XFPUTM3</data>
</table>
</table>

<table name="Fuel Pump Hi-Speed Mode, Air Temp Switches" category="FUEL PUMP CONTROL" address="19de" type="2D" scaling="Temp16">
<table name="Air Temp switch" type="Static Y Axis" elements="2">
<data>19DE Air Temp Fuel Pump switch A1 XFPUAT2</data>
<data>19E0 Air Temp Fuel Pump switch A2 XFPUAT</data>
</table>
</table>

<table name="Fuel Pump Hi-Speed Mode, Water Temp Switches" category="FUEL PUMP CONTROL" address="19e2" type="2D" scaling="Temp16">
<table name="Water Temp switch" type="Static Y Axis" elements="2">
<data>19E2 Coolant Temp Fuel Pump switch W1 XFPUWT2</data>
<data>19E4 Coolant Temp Fuel Pump switch W2 XFPUWT</data>
</table>
</table>

<table name="Fuel Pump Hi-Speed Mode, Falling Load Hysteresis" category="FUEL PUMP CONTROL" address="1a74" type="2D" scaling="Load16">
<table name="Load" type="Static Y Axis" elements="1">
<data>1A74 FP Hi-Speed mode, Load Hysteresis XPUMPAN</data>
</table>
</table>

The top table is the stock rom, the middle table is where I had it set prior to the thermostat failure, because my car ran hotter than normal, 3rd table is what I have it set to now, since my hot temp in all my scalings is the 76 Degrees C.



Edit: THis is the same as post 21:
I checked the voltage at the pump cranking, and starting. I get solid 12v at start, then drops to 8.1v at idle. So I think the ECU circuit controlling highspeed/lowspeed mode is working.

I fixed the check valve connection to the valve cover, good to go, held on for a brief test tonight in boost, that ended up way lean.

I checked the spark plugs and they looked good, except the white inner tips are no longer white, they are orange. THese are the IGR7A-G gapped at .24... I went ahead and put my Denso IW24's back in. Gonna run a test there, and see if literally, the spark plug gap is what is causing this(very hesitant). Also, 2 of my spark plug boots that connect to the coil, are a little melted on the inside around the wire clip or coil in the well that connects to the spark plug. I cleaned them out, and cleaned them up, hopefully that isn't a big issue either...

I get STFT and 02 feedback, but no trims. Drove for an hour, and nothing. I played with Periphery and all the rear o2 stock tables as well as the tephra patch. No dice.

Also no boost, can't get below 12 AFR's no matter what. Correction, plenty of boost, NO FUEL. Whether I dial up the injectors latency, lower the size scaling, nothing. She wont go below 12. Played with MAF Adder too, no joy.

Nothing has changed since the other day, when it was almost dialed in, except for trying to squeeze gas mileage out.

What circuit are the trims on in the ECM? Any way to test if I dorked this unit too, since I dorked my last one with a similar short on the fuel circuit?

Almost ready to part out and just say **** it.

EDIT: Check out post 23. EGR Vacuum hose issue.

EDIT: Fixed post 23. Still no fuel under boost. Interesting enough, Mid Trims showed up for a few, but are now gone again. Still get STFT though constant until boost.

EDIT: Post 22: Ok, so been through the whole system again, looking for leaks. It looks as though my exhaust manifold gasket is leaking on the bottom side of the manifold/block connection. See some oil and carbon deposit on the block. Would this cause a Lean condition?

Well, I finally had time to check this out. Turns out, all the lower exhaust manifold nuts were only finger tight. I think they never got retorqued at the beginning of the summer, which would have been roughly the time to retorque them due to mileage after rebuild. Another **** up from the guy in SLC who supposedly did the works on my car...
yah, he worked me over. Either way, Manifold gasket(copper) actually looked good. I loosened all bolts, and pulled manifold away and gave an inspection. I then torqued all bolts to spec, and we will see what this brings. Also cleaned up the block so if it is leaking, I will see now.

EDIT: Things looked a little better, but not out of the woods yet. Still going lean. But, I found a boost leak, I did not see the other day. Post MAF pre Turbo, there is a nipple on the FP Intake tube, the rubber cap that was on it was missing, sucking massive amounts of air in boost. You can see it in logs. AirFLow HZ on the MAF is low in boost and not hitting the numbers in previous logs prior to issue. Capped it off again, and zip tied it down. We will check again tomorrow when I have time to go play. Lets hope this was it. Cause I am out of thoughts.

EDIT: Well, results not good. I fixed the leak. I checked all hoses and tubes, the old fashioned way. I sprayed Carb Cleaner on all seams and connections. No raise in idle, no suction, no leaks. I did get the very minutest rise in idle when I sprayed the shaft seals on the Throttle Body. Either way, logs don't show a boost leak. Lean conditions are not a result of boost leaks. Usually they go rich. Boost is fine in logs, it spools fine, and hits the limits I have set, and drops to 12 AFR flat at 4K RPM'S, then jumps to 12.5 closely there after, so I let off. Airflow and Load 1 Byte, look great. JUST NO FUEL. I threw ****loads of fuel via Injector Scaling, MAF ADDER, MAF SCaling, all yielding the same results. It Stays lean at 12 AFR. Like it hits a wall at 4K. I am either guessing my MAF is taking a ****, or the fuel pump is doing something stupid. All tests suggest that the fuel pump is fine. I even pulled it over the last weekend to finally do the return mod where you drill out the Plastic Y pipe on the pump housing. Pump kicks in to high mode with the actuator and I can here it. I am at a complete loss here, and really use some suggestions. I know its not tune, I have run several of my known previous good roms, and all yield the same results. Good AirFlow, Good Load, and Good MAPPED AFR Values of what it should hit, only stays lean and rises at 4K RPM's above 12 AFR.

Thanks in advance,

Raceghost

iTrader: (4)

Bump for updates, ROM definitions, etc.

Raceghost

iTrader: (4)

Can you elaborate more please?

Fuel Pressure on the guage under hood measures @ about 40 psi at idle. Pull vacuum hose and it reads @ about 44.

Raceghost

iTrader: (4)

Umm, double check that. It's been posted and validated on this forum several times, that it is 43.5 psi @ idle with no vacuum. Under vacuum pressure it should read about 40. I also have an upgraded regulator. Running an AEM Fuel Pressure regulator with Gauge on top.

Here are my links for suggested pressure.
https://www.evolutionm.net/forums/ev...-pressure.html
https://www.evolutionm.net/forums/ev...low-rates.html
https://www.evolutionm.net/forums/ec...sure-idle.html
https://www.evolutionm.net/forums/ev...4-evo-8-a.html
https://www.evolutionm.net/forums/ev...-pressure.html

Interesting enough, this post supports your claim. I trust Dynotech tuning, and am now curious.
https://www.evolutionm.net/forums/ev...abilities.html
In reading most everything though, it seems that 43.5psi. was the suggested fuel pressure.

I need you to verify, and show me in the manual.

Please post a screen shot of the manual or book your using.

Thanks

RazorLab

iTrader: (8)

Broken ring lands? hahaha man, when does this guy get banned?

All he does is post BS for post count.

Raceghost

iTrader: (4)

Can you verify the stock Fuel Pressure for me? Dynotech Tuning and this guy suggest 33 psi at idle, vacuum line connected...

https://www.evolutionm.net/forums/ev...abilities.html

I thought sure it was ~40 psi vacuum line connected?

RazorLab

iTrader: (8)

Service Manual:



Keep in mind, this does not validate his claim of pump over running the FPR... that comes from return line restriction, not FPR.

And as an FYI, Evo 10 is ~38psi with hose on, ~45-50psi with hose off.

Raceghost

iTrader: (4)

Thanks Razor. Why does this forum in most posts I listed in previous comment/post suggest stock is 43.5psi for the 8?

RazorLab

iTrader: (8)

43.6 or so is base fuel pump pressure spec in the manual.

Most people quote fuel pressure at the rail by the base way of testing it, with the FPR hose off.

It gets confusing on the forums sometimes because most don't have that qualifying bit in their post.

Klaiceps

iTrader: (18)

Seriously. He's on some sort of crusade telling everyone their problems are caused by high fuel pressure.

Raceghost

iTrader: (4)

Ok, couple of questions for clarity.

I am at 12.5 Atmospheric pressure. If the manual says 33 psi, checked with multiple sources, including here. Where is the 33 psi measured at? Fuel Pump, Fuel Rail..?

I have always Idled at 12~14 vacuum. I have Kelford 272's. Old motor, fresh motor, no change.

What effect does this have on where I should set my AEM FPR/Gauge to? It is at the Rail.

I noticed right after installation, and setting it to 43.5, my trims were way off, +20 idle.
I lowered it some and my trims got richer. I have had several people post that higher fuel pressure means richer. Why am I seeing the opposite?

I am confused by this statement. If I have the vacuum line disconnected, I see roughly 43.5 psi at idle. I connect vacuum line and I dip to 39~40 psi 2 idle.

Where and how do I want set this for a stockish fuel pressure based on the RTFM statement, being that it calls for 33 psi?

This is your statement earlier, seem s to contradict your most recent statements, care to elaborate or clarify?

Spark plugs are good, where were you going with this? They were not fouled, and they were not baked or glazed, they are good. Still have white centers, and good tips...

I idle at 14.1~14.3V. Upgraded alternator, tuning in rom for alternator charge times, etc.

This I understand and know, how is it relative to the argument though?

Also, heres my build sheet, just incase: https://www.evolutionm.net/forums/ev...o-8-build.html. I'm not sure, but it sounds like you are talking a completely stock EVO, not a full build. Can you clarify some of the contradictions for me, knowing what's on my car?

Thanks in advance for any clarity.


Wow, can't believe I missed this. I was right. By this schematic, step 9 gives the same answer as I thought, and validated by everyone:

Step nine says, disconnect vacuum hose at idle, car warm, plug vacuum hose. Fuel pressure at FPR on the end of the rail should be 42~45 psi. The famed 43.5 PSI is correct. So where are they measuring 33psi at? My FPR says 43.5 with the procedure I just listed, when I connect vacuum, it drops to 39~40 PSI on the gauge, at the rail. Does someone care to comment?

RazorLab

iTrader: (8)

Have you tried adjusting your AFPR to ~33psi with vacuum? Will it let you? If not, then I would look towards a restriction in the return (usually at the fuel pump assembly).

Raceghost

iTrader: (4)

If I interpret right, your saying drop the AEMFPR down at idle to 33 psi, then pull the vacuum line and see how high it jumps?

RazorLab

iTrader: (8)

Yes, see if you can adjust the fuel pressure down to 33psi, and what it is after you pull the vac line.

Raceghost

iTrader: (4)

Cool. Will do that here in a couple hours, when I can be back in the garage for some test. Thank you.