# 2014 Cruze is having issues with a stubborn misfire



## snowwy66 (Nov 5, 2017)

The coil springs and the boots that go with those coil packs are also notorious for going bad.


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## patomartinez10 (Nov 2, 2019)

yea I find that to be the case. I tested the resistances of the old coil pack and the prongs are giving me considerably high resistances compared to the new coil packs (primary coils). as for the springs inside (secondary coils) the boots, I'm also getting a tough time reading the resistances compared to the new coil pack. if I get it to pick up resistance, old coil pack tends to read above 14k ohms.

the spark plugs are new, but the only thing I'd say is that the threads closest to the electrodes are black from carbon or whatever. the ground and central electrode are fine.


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## rejesterd (Oct 31, 2019)

P0301 can be caused by bad timing. You had the timing belt replaced right? That would be my main suspect after testing the plugs and coils like you did. Sounds like the belt is off a tooth or 2.


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## patomartinez10 (Nov 2, 2019)

yes, i had the timing belt replaced. i suppose i should have replaced the coils first to make sure that the timing belt maintenance could be ruled out. however, i don't think it would be timing belt. my mechanic did the work. i was alongside him, and helped him install the timing belt. it fit in nice and snug. i also drove it for ~80 miles after that work, so i imagine if it was the timing belt, then critical issues would have already arose but who knows.

the fuel pump gauge that autozone rented to me was defective, so i could not test fuel pump pressure. i'll get another set to test out the fuel pump pressure, but i think i should rule it out after the fact.

idk if this is significant, but when using multimeter on 20 dc voltage and using the leads on both connector ends (not the prongs) of the fuel injector connectors, all of the non ground connectors showed 12 V, as suspected. 3 of the ground connectors showed 2 or 3V, but the one on 1st fuel injector connector showed .18 V. again, I don't know if this is significant, but the ground connectors weren't consistent.

i will try tomorrow to check fuel pump pressure to rule it out. otherwise, i'll look into a vacuum leak, low compression, and cam/crank sensors. i also forgot to mention that i changed the valve gasket cover, since some oil was leaking inside of cylinder 2 and some drops inside of cylinder 1.


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## ChevyGuy (Dec 13, 2014)

patomartinez10 said:


> idk if this is significant, but when using multimeter on 20 dc voltage and using the leads on both connector ends (not the prongs) of the fuel injector connectors, all of the non ground connectors showed 12 V, as suspected. 3 of the ground connectors showed 2 or 3V, but the one on 1st fuel injector connector showed .18 V. again, I don't know if this is significant, but the ground connectors weren't consistent.


I'd expect the ground side to be "open", so the voltage could be most anything. However, since you have the injectors unplugged, you might ohm the injectors as well.


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## snowwy66 (Nov 5, 2017)

If the timing belt were off one tooth. The entire engine wouldn't run. 

And since he ran 80 miles before issues arose. You can most definitely rule out the belt.


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## rejesterd (Oct 31, 2019)

snowwy66 said:


> If the timing belt were off one tooth. The entire engine wouldn't run.


What would shut off the engine?


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## patomartinez10 (Nov 2, 2019)

the readings on the 4 fuel injector prongs were 15.5 or 15.3 ohms. as far as I know, as long as they are within 0.5 ohm, then it's fine. this was yesterday's reading. idk if this is significant, but the day before, the readings were like 13.7 and 13.9 ohms. idk the exact number they should be, but my car has 86.5k miles. I've heard fuel injectors begin to give out after 80k miles?


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## snowwy66 (Nov 5, 2017)

rejesterd said:


> What would shut off the engine?


If the valves aren't timed with the pistons. The motor won't run.

If the belt is off one tooth. The valves aren't timed.

I would assume that same logic still applies to today's variable valve timing engines.

The engine was driven 80 miles and the misfire problem is #1 cylinder ONLY. That's NOT the timing belt.


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## patomartinez10 (Nov 2, 2019)

update:

i ran a test with the noid lights for fuel injectors. all fuel injectors were blinking with the noid light. this confirms that power is being sent to the fuel injectors.

i ran a fuel pressure test since i finally got a non defective gauge. when key is turned to on position, gauge read a max of 61 psi, and eventually dropped to 51 psi. when turned on, the gauge maintained 61 psi roughly. i would safely rule out fuel pump as cause.

i went ahead and ran a compression test, dry and "wet" (some oil in cylinder). i have the results in the picture attached. it seems to me that I can safely rule out low compression as cause for misfire.

i also checked the fuel injector resistances and connector voltages and results are also in the picture. main takeaway is that the resistances are not consistent from day to day. 1st day was around ~13.4 ohms, 2nd day around 15.5 ohms, and today dropped to around 12.7 ohms. this might be an issue? i would like to do a fuel injector test, but i can't get a hold of the specific tool yet, but I have a feeling it may be injectors that are dirty or clogged.

i got more error codes after finishing my 3 tests. they were P0055, P0202, P0203, C342D, and C3064, in addition to P0301, P0351, and P2301. however, after some time, I erased codes and was not able to get the 5 new codes to show up again. i assume this is because of the tests i did.

next steps I wanna do are to check any vacuum leaks, but I haven't really heard anything afaik. I also want to change positions of fuel injectors, similar to how you would change a spark plug from cylinder 1 to cylinder 2 spark plug. i don't know if i could apply the same logic for fuel injectors and thus would instead get a misfire on cylinder 2. if so, this would confirm bad fuel injectors. i am so over this already lol, but i don't really want to throw more money until I am sure what needs to be fixed.


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## patomartinez10 (Nov 2, 2019)

patomartinez10 said:


> update:
> 
> i ran a test with the noid lights for fuel injectors. all fuel injectors were blinking with the noid light. this confirms that power is being sent to the fuel injectors.
> 
> ...


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## frankh (Aug 25, 2014)

Hook up your fuel pressure guage. Disconnect power plug from all injectors. turn the key on to pressurise the fuel system.. The pressure should come up and stay at high pressure whn=en the key is turned off.

If it doesn't you have an injector that is not shutting off.

Now carefully use two probing leads to power each injector.. if you can get the fuel pump to run continuosly its better for this test.. when you add 12V and ground t each injector the injector will open and the fuel pressure will drop to the same value for each fuel injector.. If #1 only drops halfway or not at all you have a fuel injector problem.

You could also move the fuel injectors to see if the problem moves.

You could also have a cylinder head gasket leak into Cyl #1.. You want to pressurise the cooling system.. preferably when warm (be careful not to get scolded!) and stick a camera down the #1 spark plug hole.. South Main Auto did this the other day on a Cruze. Check out the video below.. Of course you'd have a loss of coolant as well.


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## patomartinez10 (Nov 2, 2019)

frankh said:


> Hook up your fuel pressure guage. Disconnect power plug from all injectors. turn the key on to pressurise the fuel system.. The pressure should come up and stay at high pressure whn=en the key is turned off.
> 
> If it doesn't you have an injector that is not shutting off.
> 
> ...


thank you for your insight! I do not suspect that it is a head gasket leak because I changed the valve gasket cover recently. either way, i took a look inside cylinder 1 and it looks fine, just like all the other cylinders. plus, the coolant leaks seem to be a thing of the past now. hope it stays like that lol.

i got some fuel injectors and the fuel line for $60, brand new, so I am going to install them when they arrive soon. If this does not fix anything, then I am certain it is a vacuum leak. I am hoping the vacuum leak is attributed to the fuel line/injectors, but I was not able to pinpoint the vacuum leak location.


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## frankh (Aug 25, 2014)

The best way to find a vacuum leak is to build a smoke machine and pressurise the intake with smoke.. then look for leaks.

Don't go above 0.5psi (use a propane regulator if you want to use compressed air). There are many how too videos to make a simple smoke machine on Youtube.


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## ChevyGuy (Dec 13, 2014)

patomartinez10 said:


> The following codes show up P0301, P0351, and P2301. These codes as a quick reference say about a cylinder 1 misfire, ignition coil A primary/secondary circuit, and ignition coil A primary control circuit high, respectively.


You're looking at an electrical issue in the ignition system. You've changed the coil pack, did this go away then? If not, then you may have a wiring issue or a bad ECM.


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## patomartinez10 (Nov 2, 2019)

i just changed the the fuel injectors along with the fuel injectors, all brand new. fuel does not seem to be a problem for the misfire code. spark does not seem to be an issue. 

i will do a smoke test to see where a possible vacuum leak is coming out of tomorrow. the purge valve is working as intended, so it is not an internal leak. i am hoping that if there is a vacuum leak, it is not the PCV valve inside the intake manifold. otherwise, it will be quite expensive for that part.

the error codes i got after i changed the fuel line are P0301, P2300, P2301, and P0599. P2300 and P2301 are conflicting, as one says the ignition coil a control circuit is high while the other code says it is low. 

a new coil pack did not do the trick. it is possible that it may be a wiring issue. i was also suggested an ecm issue, so it might be that.


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## rejesterd (Oct 31, 2019)

When codes come in bunches like that, it's probably more significant than an air leak. But if it does turn out to be a bad PCV, I think they sell a repair kit for it that is much cheaper than buying the entire manifold.


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## ChevyGuy (Dec 13, 2014)

From the codes, it sure looks like there's an internal problem with the ignition. Compression and fuel are not going to set a P2300 or P2301. You've either got a bad module or a problem in the wiring or connector.


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## patomartinez10 (Nov 2, 2019)

I also think it is an electrical issue now. I took out the ECM and saw that 5/6 pins were damaged on the middle thing. I tried opening the ECM but it has a black sealant and it is hard to open!

it could also be the connector, which seems lightly damaged. it could be one the other or even both, but I am not sure because I don't know how to test it, can't open ECM, nor do I have wiring diagram to confirm these damaged pins are causing misfire!


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## patomartinez10 (Nov 2, 2019)

the ECM does not look damaged in any way, as far as I can tell


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## patomartinez10 (Nov 2, 2019)




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## WillL84 (Aug 5, 2019)

You'd be hard pressed to tell if it was bad or not by looking at it. It almost looks like corrosion on those pins. Try to GENTLY get in and clean them with a small brass bristle brush and see if that fixes your problem


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## patomartinez10 (Nov 2, 2019)

WillL84 said:


> You'd be hard pressed to tell if it was bad or not by looking at it. It almost looks like corrosion on those pins. Try to GENTLY get in and clean them with a small brass bristle brush and see if that fixes your problem


yea, I cleaned up the pins with some alcohol and a q tip carefully. as much as I could anyways. it did not have a noticeable effect. 

I want to keep checking the wires, but I don't have a wiring diagram or info that tells me which pins are for what, specifically for the ECM and the ignition coil connector (7 pins)


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## Baez521 (Nov 30, 2019)

Ever figure out the issue? My 2013 Chevy Cruze had the coil pack burn out left me stranded. I got it towed to my house and I installed a new coil pack and fuse 9 in the engine compartment as it blew out as well. After doing so the car seemed to run fine no engine light. The next day... my car is throwing a p0351 Ignition coil A Primary/Secondary circuit malfunction. Not sure what the issue is now.

I also have to mention that my coolant spewed out from the shitty coolant air bleeder hose, that connects to the coolant reservoir, onto the connectors for the ecm. I notice my pins have the same corrosion as [email protected] patomartinez10


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## patomartinez10 (Nov 2, 2019)

**** hopefully it isn't the connectors ?? believe it or not I'm still trying to fix it! but now I have "confirmed issues" from the dealer. they said they didn't see a short wire, but they know it is related to the connectors and ecm. they would like to replace the ECM and wiring harness for $3G's!!! crazy.

I went to a junkyard and managed to get the connector. I'm going to cut out the damaged wires and use a crimp connector and reinstall the connector. should this fix my misfire, I will not get an ecm. if not, I'll buy the ECM get it programmed and then install.


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## ralue72 (Dec 27, 2019)

@patomartinez10 - what's the latest? My 2013 continues to throw P0301 and P0351 and occasionally some other codes, but they never stick. I've replaced the ignition coil, spark plugs, valve cover gasket, confirmed correct load and audible "click" on all injectors, confirmed the purge valve is good... guess I'll start looking at the ECM and cable connectors/pins.


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## patomartinez10 (Nov 2, 2019)

disconnect the ECM connectors and check if there is any corrosion, rust, damage on either the ECM pins or the harness connectors. mine had liquid damage on the connectors and pins unfortunately.

the dealer recommended me to install a brand new wiring harness and ecm for a whopping $3000. lol

so I just cut like 4 wires that were damaged and heat crimped them with new ones. I only have a p0301 misfire now.

my next step is now just finding someone or a shop that can flash an ecm for me. so a new/used flashed ecm should get rid of the misfire.


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## ralue72 (Dec 27, 2019)

@patomartinez10 What do you mean by a flashed ECM? 
I'm still receiving p0301, p0351, p0261.


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## patomartinez10 (Nov 2, 2019)

it just means to have your ecm reprogrammed to the Vin of your car. if you just put on any ecm, you risk damaging electrical things and car not being able to start/run


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## patomartinez10 (Nov 2, 2019)

my car no longer has the misfire. and it was not because of the ecm. i mean there was liquid damage to some wires and ecm pins, but with some wire changes and pin cleaning, the ecm was not the issue. 

the **** ignition coils were DEFECTIVE. this is so irritating. worse thing is that a mechanic that I thought was trustworthy is claiming he fixed the ecm, but I still have the same **** ecm. it is not switched or reflashed. what's more frustrating is that chevy did a diagnostic, but they claimed it was bad ecm and wires. idk if they tried to scam me, or it was negligence, but i'm hella mad, at chevy for negligence/scamming me, my mechanic for also scamming/being dishonest, and amazon giving me a defective ignition coil pack.

now i must deal with a P0420 code, but i think I'm just going to get both O2 sensors and replace em, for preventative maintenance anyways at least. if that doesn't get rid of the code, then it is the catalytic converter. if so, GG.


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## ralue72 (Dec 27, 2019)

I bought an ignition coil from rock auto that arrived defective and had a mechanic friend say that it’s not an unusual occurrence. Very frustrating. And the rampant dishonesty is the worst. Glad you’re slowing chipping away of the easy and still beneficial fixes...


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## WillL84 (Aug 5, 2019)

Bought a starter solenoid for a boat engine from a Mercury dealer. It arrived defective (coil would switch but wouldn't make contact internally). Brought it back the next day expecting for them to warranty it and all they said was "No returns on electrical parts". Like WTF MF I'm not returning it! It's defective from the factory! Warranty it and get me a new one! They refused and just kept saying no returns on electrical parts. finally just said **** it and left. Almost tossed it through their giant pane glass window when I left


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## Blasirl (Mar 31, 2015)

Tips to ensure no misfires occur:

Remove the coil pack. If the boots are stuck on, use a small screwdriver or pick with some dielectric grease on it to go around the outside of the boot and then possibly the inside of the boot to help aid in removal. 

Remember to (p)re-gap your plugs to .028, (0.24 if tuned)

*Set gap with the black portion of this tool.*








*Measure the gap with feeler gauges.*









* Throw this away.*










Torque to 18 ft-lbs with no anti-seize on the threads of a stock type plug. 

Ensure the boots have no rips/tears or holes in them, lightly coat them with dielectric/silicone grease and make sure the resister springs are clean and not caught up in the boots when you install them.

If the plugs look bad, consider these:

*-BKR8EIX-2668* (iridium plugs), ~$25, expect ~10-15k regaps on these, ~40-50k overall life.
*-BKR7E-4644* (nickel/copper plugs), ~$8, expect 15-25K out of these plugs, with a regap or two required at 5-8k intervals on stock tune.

Read _Hesitation Gone!_ for more info on the plugs.


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