HYUNDAI ECM

JOHNDADDY

JOHNDADDY

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Good evening, all, I was given a 02 Elantra from a friend (brother) of mine after catastrophic engine failure with my truck. Bummer.
He replaced every sensor he could think of and looking at it I believe.
The ECM is the likely culprit, usually seems to be fighting with its, self. but at times runs like new.
I am constantly clearing the codes. The longer I run it the worse it gets.
lean, misfire #3, crank pos sensor, etc. etc. new exhaust cats front to rear. all sensors new.
Can I get an ECM same Calif code install and run? or do I need it to be flashed?
Sorry it's not an XS thing, that's why I put it in the lounge. Hope I'm not breaking the rules.
Internet is useless and I'm stuck two-foot driving cause now it won't hold an idle.
I soo much miss carbs and points. Fn modern junk. Ant help please.
Thanks!
 
Thanks Wingedwheel, my eyes can't handle that site, makes me blurry.
Had to leave. I did try though nothing I could find.
And I love your banner by the way, no police records either, unless they want to dig through paper. :laugh:
 
You mention that various sensors have been replaced...was this done because they were faulty?

You say you are constantly clearing codes - what are the codes indicating the fault(s) are?

Until you have drilled down and established what is causing the problem then replacing the ECM may still not fix the fault and waste more money.

First rule of diagnosis: Base any action on factual evidence not guesswork.
 
I once took away a sensor i believe it was the camshaft position sensor from my Honda fireblade
to get to the cam chain tensioner
Put it back and tried to start ..no luck . ..error codes
That sensor was factory set and not allowed to come off Not much service instructions available but at last I found some and with 2 Voltmeters I was able to readjust it .Point is it can happen that settings is needed after a replacement

The Brand dealer Sometimes have better diagnosis tools .and are Expensive. But I know of cases they immediately can find it ( Mitsubishi Space Star )
Sometimes one fault can throw many different error codes.
 
From the Sprinter van forum; a bizarre set of ECM problems was commonly caused by diesel fuel getting into a wiring harness. I suspect water or god forbid gasoline in a harness could also create crosstalk leading to errors such as your sad little Hyundai is exhibiting.

From that forum
I haven't yet seen a schematic for a Hyundai, but my Chryco minivans
have several common ground points where several circuits come to a
common ground. If one of these connections gets corroded between the
wire terminals and the chassis or comes loose from the chassis, one
circuit will be trying to use the other circuit as the ground path.
This can cause seemingly unrelated circuits to "crosstalk" and have
weird things happen. Maybe Hyunday doesn't use such a wiring
architecture, but it almost sounds like this.

IE anytime you are having oddball electrical issue go to ground(s) first.
Dissassemble scrub, lube, reattach any and all ground connections, ground straps, wires etc.
Installing a new engine block to chassis ground cable has fixed many an electrical problem. Even way back in analog (my) day.

Crosstalk​


In electronics, crosstalk is any phenomenon by which a signal transmitted on one circuit or channel of a transmission system creates an undesired effect in another circuit or channel. Crosstalk is usually caused by undesired capacitive, inductive, or conductive coupling from one circuit or channel to another. Wikipedia
 
Sensors were changed individually by the PO, he was chasing down codes trying to get the eng light out.
Finally gave up on it. Full new exhaust too, including cats. When he heard about my truck he sent it my way.
I did clean the two ground straps from the engine to frame, those were all I've found as yet.
It did seem to run better for a day or to but still bucking stalling shifting weird just not as much.
I'm clearing codes just to get it to run somewhat normal while I chase my tail.
crank sensor lean bank 1 fuel trim lean misfire #3 etc etc. definitely running wayyyy rich,
the smell is near unbearable and she's a gas hog.
I have some indoor work first then I'm going to pull the ecm.
check and clean connections probably find another ground there.
Thank you all for the imput. Right now I'm running barefoot with a ten-day temp from December. :sneaky:
 
riffing;
IIRC fuel rail pressure is usually controlled by a pressure relief spring/seat, to a return to the fuel tank line. Some part of that not open controlling excess fuel pressure?
pressure test the injectors? spray etc.
 
rich bank 1
so not pump pressure
cyl 3 is on other bank lean mis-fire

injectors are swapped bank to bank or O2's are

V6? and where are the cyls. on each bank?

in any case, new cats may be toast by now
 
Very rich exhaust, smoky dark but not when she's running right. Doesn't use oil.
I've been going to and from work only because of the sticker.
Only put about 800mi since I got it, PO put just under 400mi. When he gave up on it.
It's a 4 cyl 2.0L only has 1 bank. If I clear the codes sometimes she behaves just fine other times not so much.
The more I drive the worse it gets as it sets more codes.
Sometimes likes the cold other times not. engine does the same erratic behavior engine hot or cold.
Reading through the manual, I'm going to take a real close look at the vac lines.
 
Has a dealer hooked it up to their scan tool? I’ve found sometiimes a DYI scan tool (assuming that’s what you’re using) doesn’t have the ability to provide an in depth diagnosis. It will cost a few $ to have it done but may point you in the right direction quicker.
 
crank sensor lean bank 1 fuel trim lean misfire #3 etc etc

Ok same words as chrysler uses. Motorola ecu.

repeat exact diagnosis
example only
0339-crank/cam rationale
0341-cam sensor rationale
 
Good day all. First a clarification, apparently it's a PCM not an ECM mach nicths.
And it's an 05 not an 02, musta been thinking of my truck.
The closest dealer to me is a good hour away, that trip and expense will be the very last resort.
My hand held gives me the code # and a brief description.
Checked vac line, all good there basically just one line to the charcoal canister.
Went after the pcm and could not readily find it, got interrupted and had to put things back together.
I did manage to squeeze at some connectors, but alot more needs to be taken off to get to the pcm.
I don't/can't know for sure, but my ride in today was fairly uneventful, a couple of stumbles but real close to a normal car.
my wiggling and jiggling at the multiple connectors my have made some better connections :shrug: sill want to get in there
and make sure all connections are tight and clean. If it's something as simple as that my bros gonna want to shoot himself.
 
Yup! EVERY connector you can find; SWEAR at the SOB that designed that overly complicated POS, open, hit with spray corrosion blocker, reassemble, repeat a few times.
Hope that's it!
More than one bad running issue has been a PO that would NOT stop at the pump shut off, keeps jiggling in gas til the charcoal canister is fuel soaked................
 
AUTOMAN said:
ecu pcm whatever
codes?
Click to expand...
Ok, so for a trip back and forth to work, about 20mi
P0102 MASS AIR SENSOR
P00170 FUEL TRIM
P0016 CRANK SENSOR CORRELATION
I'll check it again at first break and see if anymore set
since my ride to work this morning.
I didn't clear codes last night.
 

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