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Bad ECU? Lean WB zero power

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snakeyes711

10+ Year Contributor
647
0
Feb 5, 2009
W-S, North_Carolina
I'm guessing this is where I need to post. My DD 1GB has a bad problem I have zero power, almost no boost charge, and it goes lean around 5K...like massive lean falls on its face and I seen 18 on the WB... didn't do that anymore. The ECU pulls back timing to nothing. knocks like crazy. No power, turbo won't spool past 4PSI. (gauge should be turning around backwards, there isn't even a line running to the Actuator)

Thing is it runs decent in Closed loop, as soon, and I mean as soon as the gauge goes into boost theres nothing it sounds like a honda.:hellyeah: The logger is working fine, and picks up data no problem, so I'm wondering if the ECU could be fine.

It doesn't overheat though things feel hotter under the hood.

Here are things I have done, and checked and replaced.

Replaced

fuel filter, FPR, wires, plugs, fuel pump, turbo, MAS

Checked

Coils, BLT, blew compressed air through the fuel lines, checked the fuel lines for flat spots, and crimps, to no avail.

Tomorrow, I'm going to pull the ECU,a nd look at the caps, here are things I've had done to the car.

GenII MAFT, LM-1 WB, 560cc Evo's(pink) 2G mas, pod filter. 16G turbo. Walbro 190, s,2G Exhaust MAn., Evo o2 2 1/2" stainless Exhaust...Can't think of anything else right now.

I am thinking about taking it back to stock parts until I can resolve this issue, as this is my DD.
 
I swear it looks as if I'm missing something that goes right here...WTF

Can anyoe confirm this? Do these spots look like a problem. Maybe the popped off?...Or bunt off?

Does this White stuff look ad or is is it thermal paste?
 

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The caps leaked and somebody did a cheap repair job on the ECU.

The white coating is what happens when they use the wrong solvent to remove the waxy conformal coating on the board. The two big green capacitors on the bottom are to replace some of the missing little SMD capacitors on the top and the disk capacitor on the cop to replace another of the missing SMD caps.
 
Ahh, I see, what are those little pieces that blew off?
 
Surface Mount Device capacitors in the two lower boxed you drew. The upper box seems to be around the corrosion to a SMD diode. You didn't mark the damage to the SMD cap by the processor where you can see the wire come through the board and connect with the pin on the CPU.
 
Oh I gotcha now, the only reason I circled the upper ones its because I felt that those two spots had once had something there, about that size. I was sure of it.So your saying the orange disc cap, and the two green ones are to replace the ones missing... Can this one be repaired. I read an article about the ISC going bad that can ruin your ECU, I'm wondering if the drivers they were talking about are shot...Or the whole unit is shot? I found a good eprom on ebay for 260. thinking maybe I could get this one fixed as Spare.


Not sure what other damage you see by the processor?
 
....whatt now?...New ECU didn't solve the problem.............................................................

I would just get a new ecu and be done with it. $260!?! You really should keep an eye out on the classified section here on tuners. Just taking a look right now, I saw a 1g eprom going for $80...

1g Eprom ECU *reduced* - DSM Classifieds

I'm going to cry........
 
Did you get one locally, or have someone overnight ship it?? How'd you get another one so fast?

Check the fuel pressure? Fuel pump voltage? MAFT compensation?
 
Did you get one locally, or have someone overnight ship it?? How'd you get another one so fast?

Check the fuel pressure? Fuel pump voltage? MAFT compensation?

Yeah over nighted....And that was not the problem.....:(:beatentodeath:

Checked fuel pressure, changed the pump, got 12V at the pump Changed the Injectors out a wile ago. Same difference............Did I mention I got a 280 dollar ECU for nothing?

I don't get it, It starts, and idles fine. Cruise is ok, As SOON as you put load on it boost gauge rips out 4PSI, then about 4-5K BOOM totally lean if I back off the WB stays lean for 10 seconds before it goes back to normal.
 
I can post a log but I cant post the WB as its not tapped to MMCD.
 
I still have never solved this problem I've changed a lot of parts, and checked a lot of things. Nothings works. I seen iun the MMCd logger I'm getting 9.9MS on injector pulses when I get on it.....I'm at a loss.
 
It has a brand new OEM Wastegate actuator, and it is connected. Plus it shouldn't peg out lean if the wastegate isn't connected.
 
I just got time to test all the engine sensors,and were all good. I am thinking I'm barking up the wrong tree? Maybe its Mechanical?
 
Ok, Wisemen. I need to know everything that could affect the injector pulse, or its timing or both and everything that tells the ecu when to add fuel, how much, and what affects timing. I still haven't solved this problem, and I'm aggravated beyond belief.

The things I know to be good are, TPS,pump,regulator,mas,turbo,ecu. I checked ALL pins off the ecu, and there are no breaks or shorts. Unless, this ECU has the exact same problem the other had. Also the idle valve works all the coils are in specs. the car runs and drives normal.

Its almost like the injectors are limited to the fuel they deliver. The plugs are bright white. And I'm outta options. I want to get this EVO8 but I've got to fix this car first.
 
Its your wideband sensor going out, try puttting stock o2 sensor. Or you o2 sensor going out one of those 2
 
had both, WB showed full lean on any throttle. open loop, its all lean. every things stock now, and its still the same. logger shows stock o2 working...

also in open loop does the o2 determine fuel?
 
O2 isn't used during open loop, IPW is pretty much determined by the amount of airflow and what RPM. Since a new ECU didn't fix the issue, its got to be between the in-engine harness and ECU. Check the new ECU now to see if anything got fried again, just fixed a car with a bad wiring harness and it killed 3 ecus till we re-did the WHOLE wiring harness. How much boost are you building before 4500-5000 RPMs? What spark plugs are you using and what are they gapped at? With autolites in one of my DSMs, I wasn't able to get the car above that same RPM range with the same results. Changed to BPR6ES and fixed. Since you're apparently running lean ALL the time, something might be wrong with your O2 sensor as well. O2 sensor kicks on at idle and cruise using fuel trims to keep the car from running too rich or lean. My car ran lean at idle and cruise, but it was only slightly lean, and I am fairly certain that it was from my exhaust leaks/boost leaks. You should find out what sends engine speed to the ECU.
 
not running lean at cruise, only any more throttle then that. someone go check the yellow with green stripe wire coming from the coolant temp sensor resistance to ground. Just on ground I'm reading 550 ohms. And the other wire is 5 ohms at the battery.

I'm thinking this may be the problem. The green wire black stripe is the sensor ground. Though that yellow with green stripe wire runs to the ECU. And I'm reading pretty high resistance, and this might just be the problem if the ECU thinks the car is 400 degrees hotter...

or not, I got positive connections between both the CTS, and the sensor ground wire...but I get infinity between both the wires now why is that.

O2 isn't used during open loop, IPW is pretty much determined by the amount of airflow and what RPM. Since a new ECU didn't fix the issue, its got to be between the in-engine harness and ECU. Check the new ECU now to see if anything got fried again, just fixed a car with a bad wiring harness and it killed 3 ecus till we re-did the WHOLE wiring harness. How much boost are you building before 4500-5000 RPMs? What spark plugs are you using and what are they gapped at? With autolites in one of my DSMs, I wasn't able to get the car above that same RPM range with the same results. Changed to BPR6ES and fixed. Since you're apparently running lean ALL the time, something might be wrong with your O2 sensor as well. O2 sensor kicks on at idle and cruise using fuel trims to keep the car from running too rich or lean. My car ran lean at idle and cruise, but it was only slightly lean, and I am fairly certain that it was from my exhaust leaks/boost leaks. You should find out what sends engine speed to the ECU.

4-5 psi. NJK BPR6's plugs gapped at .026 or so, just gapped stock maybe a tad lower. as far as engine speed you talking about the the tach wire?...

And heres the thing, when I swapped in a 1G automatic fuel pressure regulator it will build a few more PSI....WHATS THAT ABOUT! I'm at a loss.

Also, I KNOW... I checked every. single. pin on the ecu, and got good connection.

Oh, one more thing on the ECU pin out, it shows a black wire as, crank angle sensor(RPM).
 
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