2G Stock GSX missfire

[605jdm]

I just bought my gsx and drove it home for about 5 hours then a few days later the check engine light came on and came up as a missfire on cylinder one and I could hear it too. I got new heat 7 spark plugs and ngk wires and checked the spark that was all good but it's still miss firing. Please help I can't figure it out. Also my mpg dropped to 17mpg.

 

[chrysler kid]

Never heard of heat 7 spark plugs

 

[C'LO]

I think he meant BPR7ES

 

[605jdm]

I think he meant BPR7ES

yea have those! couldn't remember the name

 

[DeadlyAKrunna47]

This guy is cluttering the forums with his problems.

btw everything has already been asked before. If these cars dont make you a mechanic then there is no faith in keeping it, if you want the honest truth.

 

[oneslowwdsm]

Did ya check the CEL?

 

[605jdm]

Did ya check the CEL?

Yep, said it was a misfire in cylinder one.

Could their be a fuel problem?

 

[oneslowwdsm]

Well start by checking spark on cylinder 1. Pull fuel injector clip while the car is idling, if nothing changes then you found your problem.

Source:
http://www.dsmtuners.com/threads/cylinder-1-misfire.382166/

http://www.dsmtuners.com/threads/cylinder-1-misfire-4g63.461084/

http://www.dsmtalk.com/forums/showthread.php?t=58768

 

[605jdm]

its getting spark i checked all the plugs by holding them on a ground.

 

[GSXvsTSI]

Unplug one injector at a time to see how that affects it at idle(sometimes you can tell which injectors are working by touching/listening to them). That will tell you what cylinder it is. Could be a bad ECU driver or bad injector.

 

[605jdm]

Alright i will try the injectors today hope thats all it is because im upgrading anyway.

 

[605jdm]

I pulled out all the injector clips one at a time and it didn't stay the same for the first one. The engine just shook and ran really bad.

 

[GSXvsTSI]

They should all do that to the engine except for the one that is jacked. When you pull that one it won't make a difference.

 

[Jacolu3]

I had a similar problem a few months ago and it turned out to be a bad coil pack. Wouldn't hurt to look into that.

 

[PrimerPLus]

Possible bad Coil Pack, Bad Power Transistor, Bad Cam Position Sensor, plugs, plug wires, clogged injector, dying injector

 

[Lou98GSX]

if you have spark and you already tried plugs then you should swap # 1 injector with # 4 to see if the misfire changes . also did you check compression cause maybe it could be a mechanical problem .

 

[605jdm]

if you have spark and you already tried plugs then you should swap # 1 injector with # 4 to see if the misfire changes . also did you check compression cause maybe it could be a mechanical problem .

I already tried swapping them I will get a compresion check I guess. It that comes up good what else could it be?

 

[jimsgsx]

Sounds like injector 1 is stuck open.

 

[Slowdoorwedge]

Just a side not, my buddy picked up those same plugs for his car. Drove it for about an hour and misfire. We swaped the plug to a different cylinder and that cinder then miss fired. Turns out one plug was bad from the factory. Replaced bad plug and no more misfire. Just a though guy at napa said it is fairly common to receive a bad plug.

 

[C'LO]

Have you checked the gaps in the plugs themselves?

 

[BlackWaspBG]

Check injector resistance, clean all of them, change spark plugs( just because they are cheap), BLT

 

[605jdm]

All the spark plugs are gapped right to 28 i believe. I will try swapping the injectors around and see if it switches.

 

[97gsxIA]

As what others are mentioning, swap the injector/plug/plugwire with another cylinder's and in different intervals and see if it jumps to a different cylinder. That will rule out bad injector, bad plug, bad plug wire. Test your coil pack and CAS with a ohmometer. then check your fuel pressure.

These are your only options.

 

[JS4G63]

Does your problem come and go, or is it always misfiring? I had an intermittent misfire issue once... it would run fine when the engine was cold, and start misfiring after fully warmed up. Bad power transistor - I could put it in the freezer and then the car would run a little longer since the transistor took longer to heat soak. Whenever it got hot enough, it stopped energizing one of the coils and caused the misfire.

 

[605jdm]

Does your problem come and go, or is it always misfiring? I had an intermittent misfire issue once... it would run fine when the engine was cold, and start misfiring after fully warmed up. Bad power transistor - I could put it in the freezer and then the car would run a little longer since the transistor took longer to heat soak. Whenever it got hot enough, it stopped energizing one of the coils and caused the misfire.

its always going and started getting really bad because my alternator is going out. I ordered a new one and will see what that does to fix it. After that im getting 850cc injectors.