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Hello.
I learned soo much from your YouTube vids man I think your doing the world a favor.
I have a 2003 Mitsubishi lancer evolution.
In winter I give the car a rest.
I went to go start it one day and no start and no fuel.
Crank sensor ofcourse.
Replaced and it started but only on 2 cylinders.
1 and 4 no spark.
2 and 3 spark.
Jumped signal wire from 2 and 3 to 1 and 4 (with coilpacks out ofcourse) and it sparked.
fuel is good (plugs are wet)
tested 1 and 4 coilpack connectors and the reading are.
12 B+
.30 signal
12 ground.
tested ecu ignition signal wire for 1 and 4.
.30
ecu is sending out very low voltage hence no spark.
replaced.
redid the timing belt
ECU
crank sensor
cam sensor
ignition switch
coil packs
spark plugs
ecu is sending out very low voltage hence no spark!
What exactly does this mean? How did you measure the trigger signals from the ECU to the coil? These are usually low voltage signals hovering around 5 volts (+/- 1V).
Do you have a scope at hand?
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
hello.
I checked with a volt meter, im not sure if that would read it correct?
I tested the signal with at
coil packs
and ecu.
the wiring between the ecu straight to the coil pack is fine.
i hot wired the signal wire from ecu to coil pack to see if it would change anything but nothing.
i moved this issue to diagnostics, sorry for posting in wrong location.
Thank you !
Ecu pin 10 is for coil pack 1 and 4.
to see if there was a wiring issue in the signal wire from ecu to coil pack.
I cut the wire from ecu (3 inch from ecu) attached a wire from there straight to the coil packs.
No change.
Same voltage.
Today i tested the cam and crank sensor signals to ecu.
cam sensor reads
12v power
5v signal
12v ground
Crank sensor
12V power
2.1V signal
12v ground
Crank sensor signal should be 5V. Any reason why it would read lower?
Sounds like your powers are normal-(this usually depends on make/model). As far as your Crank signal being 5V, to properly test, you need to remove the fuel pump relay, connect DMM (-) lead to Battery (-) and touch DMM (+) lead to signal wire while having someone crank the engine. You should measure 300mV. The grounds should not have Battery or 12V. You might have a short-to-ground on them. Do both Cam and Crank sensors share the same ground? I would attack the ground wires and then pull both sensors out and do a resistance test and compare to specs. Did you check all the grounds-(engine, chassis and others). Good luck and let us know what you find.
"The object of war is not to die for your country but to make the other bastard die for his"
Hello.
Yes I tested the signal wire the way you explained it above. it reads 2.1-2.6V around that area.
I'm not sure if I can provide pictures of the reading here?
Cam and crank do not share the same ground.
i tested cam sensor reading and that has no issues.
5V reference, good power and ground.
Also tested resistance and manually turned the motor to see if it would read zero when the reluctor wheel passes it. Cam sensor passed.
I tested the cam sensor signal same was i tested crank signal wire.
Cam sensor had 5V
crank had 2.1-2.6
Spec for crank is 5V.
I will retest my ground wire at crank sensor connector.
I may have been doing it incorrectly.
All ground wires have been removed, cleaned and reinstalled.
Ok- sounds like your on the right track. While your at it, you might want to look over any fuses that may relate to the areas of concern. Good deal- you'll get it. Remember- Rome was not built in a day
"The object of war is not to die for your country but to make the other bastard die for his"
I cant thank you enough for your time and help.
I hope i figure it out.
I put in months building it from ground up, only drove it for a month and parked it.
Really want to get back in it.
I checked fuses and there is a MFI relay, replaced and tested, it clicks.
Today i tested the cam and crank sensor signals to ecu.
cam sensor reads
12v power
5v signal
12v ground
Crank sensor
12V power
2.1V signal
12v ground
Crank sensor signal should be 5V. Any reason why it would read lower?
Couple of things come to mind. When you tested those grounds did you have your DVOM neg lead connected to the sensor ground and the DVOM pos lead to battery + or to the sensor 12v feed?
When you test those 5v signal wires you should disconnect both coils at their electrical connector before testing.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
Hello.
I have a basic harbor freight multimeter for these test.
I connected the Red probe to the signal wire and the Black to chassis.
Car in on position will read 0 (Meter on DCV) when started on 2 cylinders it reads 2.1V
i will be redoing the ground test to get a accurate reading. I am off only one day and come back late from work so don't get to test often, sorry.
You're voltmeter is showing you an average reading, this means it will sample 3 or even 4 times per second and display the calculated average of these samples...
The signal itself switches from high (12v or 5v, depending on sensor design) to low (0v) and the meter does its thing now coming up with an average value. Depending on the reluctor design these average values of crank and cam sensors may we'll be different from each other and yet be ok.
You may want to measure the ckp and cmp signal with the switch in the on position, engine off and turning over the engine slowly by hand. Make sure it want start by disconnecting the coils, for example. While spinning the crankshaft you now should see two distinct voltage levels for each sensor - high and low - on your meter.
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
Good to hear. When at all possible, hook up your meter or test light to Battery ground. This way, you know without a doubt, that your on a good ground. Whats the MFI relay for? Im asking because Im not familiar, but gimme an M60MG or M240B and I can mow down some trees- Let us know what you find in any further testing- Good luck
"The object of war is not to die for your country but to make the other bastard die for his"
You have one working coil which suggests the crank sensor is sending a good signal however, it is not reaching coil pack 1-4. If the wiring diagram you posted is accurate, then the 2.1v you're seeing is a bias voltage. Notice the resistor attached to the transistor (within the ECM) to each coil. The 5v signal from the crank is not activating the 1-4 transistor in the ECM so no spark. The system is pull down design. That why 12v on ground connected with KOEO or KOER. Current is flowing to ground, the coils are building their magnetic fields waiting for their transistors to shut off to produce spark.
With all that said, I wonder if as a work around, you could use the 5v signal from the ECM driver for coil 2-3 to drive 1-4? Tap into that good 5v and tie it to that cut wire to 1-4. IMO you should now have spark at both coils.
This suggests to me the ECM has an internal problem with the 1-4 driver.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
Hello.
Yes i tried this,
I jumped the signal wire from 2 and 3 and connected it to signal wire 1 and 4.
she sparked. i had coil packs out of the cover because this would obviously case a serious misfire.
i replaced the ecu. i now have 2 ecu's, highly unlikely that both of them are bad.
I send both ecu to my tuner and he tested them with another EVO 8, it started.
Have to apologize, in all the posts, I lost that you only have 2.1--2.6v on the crank sig wire. I got my wires crossed. The crank sig is what controls the coils firing. You did not mention checking coil pack 2 -3 for voltages and I think that's where I mixed things up with the cam sig 5v. My bad :dry:
My suggestion won't work as you do not have the required 0-5v on crank sig. Which takes us back to the crank sensor and it's 12v on it's ground. With the CKP sensor unplugged KOEO do you have 12v still on the ground? On the harness side.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
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