Engine misfire ?

Good evening,

The first thing that comes to mind is a crank sensor. It can cause momentary cutout and still not code.

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor

This guide can help as well

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

It is located by the oil filter and a simple repair. It had nothing to do with your tire replacement. Check out the diagrams (Below). Please let us know what happens.

Thanks for the answer Roy. I appreciate the quick response and I will give it a shot.

Sounds good.

Keep us updated.

Always glad to help.

Roy

So I replaced the crank sensor and still the same issue. I am at a loss. Someone mentioned that maybe the MAF sensor or a vacuum leak is causing this. But I am baffled as to why I am not getting any codes.

The next step I would do is a compression test to be sure all the cylinders are good.

https://www.2carpros.com/articles/how-to-test-engine-compression

Roy

The vehicle took too long to start and finally did start. The engine trouble light came on and also the VGA light. On restarting the engine the engine light stayed on and the VGA light went out. after going about 5 miles and restarting the engine again the vehicle idles okay, but when you accelerate it starts misfiring and loses power. a month ago Honda service had relearned the CKP sensor, but it seem not to help. I took it to a mechanic and he relearned it again, but I don't think it will last.

Hello,

It sounds like the car is going into limp mode due to a dirty throttle bore. this guide can help us fix it.:

https://www.2carpros.com/articles/reduced-power-limp-mode

We should run the codes as well.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please run down these guides and report back.

posted ;that post, unfortunatly, misfiring and random misfiring was back with car cabin smelling of fumes.
after 4 mechanic .,whom, took the easy way out, got car back with same problem. mind u readers i was burning oil with misfiring,car idleing funny,exhuast sputtering at the end pipe.all mechanic suggested it was normal.1 daring mechanic open the head; replace vavles ,put head back.misfiring went away,,but got code072and075 bank 1 and 2 running rich.took head out to redo.clean fuel and intake. i was overjoy to say.got car back with no check engine lite ,no funny idle.no fuuny exhuast or gasolin fumes or exhuast sputter sound .spend a bit of money,had already spend much trying to fix it from advise on most car furom.car has 50,000.wanted to save it at all cost.if a mechnic had suggested . bad valves and seals,i wouldn't have spend money on plugs ,injector etc. any i hope this help some one.mine car had 2 bad valves all mechanic said my compression was up to par, accept 1, who perform a dry and a wet run, suggested it was mechanical problem in 2 cylindas that were below par. good luck

Thank you for the input. It definitely is going to be helpful for others.

Have a nice day.

rx7 06 honda 6seed manual car still running great .code corection ,1072and 1075.instead of 072/075 in my previouse forum.a point to mechanic regular compression check do not tell the full detail in engine. until booktext is aplied with the additions and substractions.
also while my car idled rough when test driving ,it sprinted with no problem.given the mechanics to think the was nothing wrong in the engine.all reading to computer checked out find.accept the misfire and random misfire/,all was having a hard tme diagnosting.also when client
complian about fumes in cabin most mechanic think its imposible,i experience.it went away when repairs was finally made to the engine.hint machanic or a friend test driving the a day wuold come to conclusion thers no fumes or smell.have to drive car for few daysto note that problem.car owner has inhailed so much fumes ,sticking thier head inside the car alone, would notice the smell of fumes.cobination of exhuast and gasoline smell. thanks to all mechanic on site goodluck.

correction,/friend test riding the car for a day, have to dive the car for a few days

engine seems to run fine at start-up but within 5 min jerks over 2500 rpm and if more throttle is applied engine goes to idle. put a new throttle positioner on the car and disconnected the battery while doing so. still does the same thing. engine light comes on right before this starts. have also had one other problem recently, shifter safety lock comes on sometimes and locks the shifter either on start up or even when the shifter is put into park with the motor runing.

Hi wringo,

You need to scan to find out what is wrong as the Check Engine Light was showing.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Check the Brake lights, if they are not working the gear shift would be stuck in Park unless you manually release it with the key slot.

So a few days ago my car whenever the RPM's go above 2,500 it starts jerking like there is a governor on the car. If I am driving and the RPM's are below 2,500, I do not notice any problem shift gears or anything. I also put the car in park and revved the engine and soon as it goes above 2,500, the RPM's start going up and down. When shifting gears, the transmission is not slipping.

Thanks for your help in advance!

Hi muhaha,

This sounds like a typical ignition system breakdown due to worn out spark plugs. Here are two guides to help us get the problem fixed:

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

and

https://www.2carpros.com/articles/how-to-tune-up-a-car-engine

Please run down these guides and report back.

Cheers

Yes, I had this problem after the tune up it run perfect! I love this site.

04'honda accord engine light is on, My engine will miss/hesitate when trying to accelerate at any speed above 40 mph. When going at speeds below that the car accelerates fine. PLEASE HELP!!!

Have codes read at most autoparts stores for free, post codes in this thread.

I agree with mmprince 4000, The thing to remember is if they clear the code it will reappear after forty miles of driving. That is when the computer resets and the engine light will come back on if the problem is not corrected.

Random misfire in several cylinders 2,4,6,5 have did coil pack plugs and erg now what to try

DTC P0300: Random Misfire and Any Combination of the Following:

DTC P0301: No. 1 Cylinder Misfire

DTC P0302: No. 2 Cylinder Misfire

DTC P0303: No. 3 Cylinder Misfire

DTC P0304: No. 4 Cylinder Misfire

DTC P0305: No. 5 Cylinder Misfire

DTC P0306: No. 6 Cylinder Misfire

Special Tools Required

Pressure gauge adapter 07NAJ-P07010A
A/T low pressure gauge w/panel 07406-0070300
A/T pressure hose 07406-0020201
A/T pressure hose, 2,210 mm 07MAJ-PY4011A
A/T pressure adapter 07MAJ-PY40120
Oil pressure hose 07ZAJ-S5A0200

NOTE:

If the misfire is frequent enough to trigger detection of increased emissions during two consecutive driving cycles, the MIL will come on, and DTC P0300 (and some combination of P0301 through P0306) will be stored.
If the misfire is frequent enough to damage the catalyst, the MIL will blink whenever the misfire occurs, and DTC P0300 (and some combination of P0301 through P0306) will be stored. When the misfire stops, the MIL will remain on.
Troubleshoot the following DTCs first, if any of them were stored along with the random misfire DTC(s):

P0107, P0108, P1128, P1129: Manifold absolute pressure (MAP) sensor
P0171, P0172: Fuel system
P0335, P0339, P0385, P0389: Crankshaft position (CKP) sensor A/B
P0506, P0507: Idle control system
P0340, P0344: Camshaft position (CMP) sensor
P0401, P0404, P0406, P2413: Exhaust Gas Recirculation (EGR) system

Note this freeze data:

Engine speed
Vehicle speed
Throttle position
CLV

Clear the DTC with the HDS.
Start the engine with no load (in neutral), then let it idle.
Monitor the OBD STATUS for DTC P0301, P0302, P0303, P0304, P0305, or P0306 in the DTCs MENU with the HDS.

Does the screen indicate FAILED?

YES - Go to step 9.

NO - If the screen indicates PASSED, go to step 5. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, wait for several minutes, then recheck.

Check the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, CYL4 MISFIRE, CYL5 MISFIRE, and/or CYL6 MISFIRE in the DATA LIST for 10 minutes with the HDS.

Does CYL1 MISFIRE. CYL2 MISFIRE, CYL3 MISFIRE, CYL4 MISFIRE, CYL5 MISFIRE, and/or CYL6 MISFIRE show misfire counts?

YES - Go to step 9.

NO - Go to step 6.

Test-drive the vehicle for several minutes in the range of the recorded freeze data.
Monitor the OBD STATUS for DTC P0301, P0302, P0303,P0304,P0305, or P0306 in the DTCs MENU with the HDS.

Does the screen indicate FAILED?

YES - Go to step 9.

NO - If the screen indicates PASSED, go to step 8. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, go to step 6 and recheck.

Check the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, CYL4 MISFIRE, CYL5 MISFIRE, and/or CYL6 MISFIRE in the DATA LIST for 10 minutes with the HDS.

Does CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, CYL4 MISFIRE, CYL5 MISFIRE. and/or CYL6 MISFIRE show misfire counts?

YES - Go to step 9.

NO - Intermittent failure, system is OK at this time.

Turn the ignition switch OFF.
Check the fuel quality.

Is the quality good?

YES - Go to step 11.

NO - Drain the tank, and fill it with a known-good fuel, then go to step 20.

Inspect the spark plugs. If the spark plugs are fouled or worn, replace them.
Test-drive the vehicle for several minutes in the range of the recorded freeze data.
Check the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, CYL4 MISFIRE, CYL5 MISFIRE, and/or CYL6 MISFIRE in the DATA LIST for 10 minutes with the HDS.

Does CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, CYL4 MISFIRE, CYL5 MISFIRE, and/or CYL6 MISFIRE show misfire counts?

YES - Go to step 14.

NO - Go to step 20.

Check the fuel pressure.

Is the fuel pressure OK?

YES - Go to step 15.

N0 -

If the pressure is too high, replace the fuel pressure regulator, then go to step 20.
If the pressure is too low, check the fuel pump, the fuel feed pipe, and the fuel filter. If they are OK, replace the fuel pressure regulator, then go to step 20.

Turn the ignition switch OFF.



Remove the VTEC oil pressure switch (A), and install the special tools as shown, then install the VTEC oil pressure switch (A) in the pressure gauge adapter (B).

NOTE: Install the switch in the reverse order of removal with a new O-ring.

Reconnect the VTEC oil pressure switch 2P connector.
Start the engine. Hold the engine at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on.
Check the oil pressure at engine speeds of 1,000 and 2,000 rpm . Keep the measuring time as short as possible (less than 1 minute ) because the engine is running with no load.

Is the oil pressure below 49 kPa (0.5 kgf/sq.cm, 7 psi) ?

YES - Check for air in the fuel line, then go to step 20.

NO - Inspect the VTEC system, then go to step 20.

Turn the ignition switch ON (II).
Reset the ECM/PCM with the HDS.
Clear the CKP pattern with the HDS.See: Powertrain Management\Computers and Control Systems\Engine Control Module\Testing and Inspection\Programming and Relearning
Do the ECM/PCM idle learn procedure.See: Powertrain Management\Computers and Control Systems\Engine Control Module\Testing and Inspection\Programming and Relearning
Do the CKP pattern learn procedure.See: Powertrain Management\Computers and Control Systems\Engine Control Module\Testing and Inspection\Programming and Relearning
Test-drive the vehicle for several minutes in the range of the recorded freeze data.
Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P0301, P0302, P0303, P0304, P0305, or P0306 are indicated, check for poor connections or loose terminals at the ignition coil, the injector, and the PCM, then go to troubleshooting DTC P0301, P0302, P0303, P0304, P0305 or P0306. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - Go to step 27.

Monitor the OBD STATUS for DTC P0301, P0302, P0303, P0304, P0305, or P0306 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete.

NO - If the screen indicates FAILED, go to step 1 and recheck. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, go to step 25 and recheck.

Car has new plugs, cool packs, timing belt, but it will get a misfire at idle sometimes. It does this mostly between fifty and sixty mph. it shows to be misfiring on all six, but there is no way the car runs to strong. what should I check next? Thanks

Check fuel trims. If running on the rich side then do a valve adjustment when the engine is cold. You will find most of the exhaust valves are going to be tight. Good luck and let us know how it goes.

my malfunction indicator lamp came on a couple of days ago. I took it to the dealership so they could tell me what was wrong with it, they said it was a misfire. Is it safe to drive still? they can't fix it until Monday, and today is just Saturday. And how much would the average cost be??

Misfiring could be due to various factors and the cost would depend on the amount of parts to be replaced. The most common parts that require attention would be the spark plugs.

You can continue to drive the vehicle but if it is misfiring badly, the catalytic converter might glow red hot while driving. If that occurs, it is not advisable to continue driving as it could damage the catalytic converter over extended periods.

car was running fine. turned it on and within 30 seconds the TCS light and check engine light came on and car started shaking, idling funny. put on code sensor and came back with faulty P301, P304, P306, and P300 multiple cylinder misfires. no other faulty codes, nothing for the TCS , drove car home and two day later made sure gas cap was on tight and restarted and did another check and same codes came up. I read it is okay to drive with TCS light on, but can I continue to drive it with the cylinder misfires?

Welcome to 2CarPros. It's not really good to drive with the misfires, especially if the CEL is flashing. The reason for this is that the misfires will cause unburned fuel to enter the catalytic converters and this can easily damage them to the point they have to be replaced.
Because this was a sudden thing I doubt it is spark plug failure as they seldom fail as a group. However if they have not been changed in a while it would be a good first thing to check. Next would be to check the power feed to the coils, look at the wiring harness that the coil wires go into and look for damage or rubbing. All of the coils are fed from one fuse but because the engine still runs the fuse is good. Another thing to try, if the CEL isn't flashing would be to clear the codes and see if they suddenly come back. It is very possible that they were caused by a cascade effect where one cylinder dropped out but it causes a "false code" on the cylinders around it in the firing order. If you get back the same cylinder codes ((the P0300 is because you have three cylinders (1, 4 and 6) reporting a misfire)) Then I would likely change the plugs and see if the codes are still present. If the scan tool you used can view live data it might also give a clue as to the problem, but only if it shows the misfire counts.

Thank you.

STEVE W. is one of our best! Please let us know what you find. We are interested to see what it is.

Hello. I have the codes p0304, p0303, p0300, and p1399. I've replaced the vtec sensor, spark plug wires, cap, and rotors, just had an oil change. I once had codes for vtec system malfunction which led me to replace these parts. The codes listed above are new, as the light just came on immediately after replacing these parts. What could this be? Bad spark plugs? I had a smoke test ran and they said the evap canister may be the issue but I tested it and it still works. Idk what to do here, with only a day or two to pass inspection I'm pretty desperate to find the issue thank you!!

When you did the tune up did you use OEM parts? cheap tune up parts can cause these issues. Here is a guid to help you do the job right.

https://www.2carpros.com/articles/how-to-tune-up-a-car-engine

Please let us know what you find.

The engine is running very poorly at idle but the problem is virtually gone once i get going. So I got new tune up parts from Honda and now the car runs great! good call.

Good to hear, please use 2CarPros anytime we are here to help.

Cheers

Hi. I have a 2002 honda accord. The otc scanner reads codes p1399 po300 po301 po302 po303 po304 po305 po306. The map sensor and others all seem to be within their parameters. The Honda dealer wants to throw parts at it because they cannot figure out the problem. Someone told me it could be the EGR valve even though I do not have a code.The engine hesitates when you first put your foot on the throttle and is worse when the engine is cold. Any ideas. Thanks

Is this the v-6 with v-tec? If so I had a very similar problem on a customers car. His car would drive ok until you would try to accelerate hard then at about 3500 rpms it was like you were hitting a rev limiter. You have a similar car and codes. Can you tell me more about how the car runs and drives under normal and hard driving. His car turned out to be the v-tec soenoid.

Hi David,

Well as you probably know the 300 -306 codes are all misfire codes. the 1399 code I am not to familar with but have found a few places that indicate EGR Valve.
So try removing the vacuum line from it and see what happens or if you can remove it and clean it out.

And when was your last Tune Up?

Also will need more info on your vehicle....

for the vehicle year I need the Month and Year,
The Sub Model - EX, DX, LX
The Engine Size In Liters
Is it a Hybrid or not.


.

Car will not start unless cranked until battery is about dead. after it starts it will not idle in gear at all, and when pulling even a slight hill it starts surging until you take it out of cruise or back way off the power. only codes are cylinder 1, 2, 3, 4, multiple and random misfire. put new fuel pump in tank, new injectors, and a new distributor. after I put the distributor in and new wires it took a week to get started again. a lot of times after it has started it goes down the road pretty good just have to put it in neutral or it will shut off and barely restart. put new crank sensor in it also.

Good morning

Did you check the compression in the engine?

https://www.2carpros.com/articles/how-to-test-engine-compression

Wondering if the timing belt may be worn out.

https://www.2carpros.com/articles/how-a-timing-belt-works

Are there any other codes besides the misfire codes?

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Roy

I had been driving the car for about 170 miles at 65-75 miles/hr. The engine light started blinking. The preformance was normal. The manual stated it might be the gas. I filled the tank. The light went out for about 20 miles. When the light came back on the car had no acceleration. I took it the Honda dealer. I thought the car was going to die at the light. When the dealer checked the car the light went out. At 1st they said there was no problem and we could proceed on our trip. We didn't feel safe. They found oil in the 4th cylinder. Honda tech service had the head removed. I was told the valve seal was defective and they repaired it. I'm told now the car is ready. I don't feel comfortable the car is repaired. The problem only seems to happen after driving highway speeds for hours.

Hi techwizard852,

Thank you for the donation.

For misfiring to be recorded, it might at times takes some driving before it is recorded and illuminates on the Check Engine Light.

The problem would not cause the vehicle to breakdown though it would affect the performance and fuel consumption.

As repair had been carried out, you would need to do some driving to confirm if it had been resolved. As vehicle is still under warranty, if the problem reoccurs, you can always get back to them.