Ive had the dreaded P1320(ignition signal) code appearing 1-2 times a week.
Its been occuring since early November. The only other code ive had is a P0320 (cylinder 4 misfire)...but that only happened once. I checked my coils/connectors and noticed no obvious defects. The car occasionally starts up poorly and only runs on 5 of 6 cylinders for no more than 25 seconds before returning to normal and running fine.

Could this be due to the cold weather?

Its been below 20 for a couple days and it seems that the colder it is the more likely the P1320 code is to occur.

I read a few places that its just the cold temps that make it have issues.. but if its something more than that id want to fix it asap.

Thanks in advance to anyone who helps out!

 

SOS
The codes actually P0304 for the 4th cylinder misfire..
1/5 times I start the car it misfires while in Park and in reverse. As soon as its in drive it goes away after a few seconds. I checked the ignition coil again and its not damaged(P1320 is really confusing me ) what are the other causes of an intermittent misfire.. im desperate. I dont wanna blow my cat converter

 

Just cause the coil "looks" good doesn't mean is working properly. Check the spark plug, and even the coil boot. Those are the "usual" misfire suspects. If you replace the coil, PLEASE buy OEM or you are not going to know for sure if you fixed the problem.

 

Same thing for P1320 - looks like again ignition coil, spark plugs, and even MAF

 

Alrighty, thank you! Will be checking plugs momentarily

 

I was having the same issue. Random Misfire code p1320. It turned out to be that the wires to one of my fuel injectors (bank 2) was torn a lil bit. I retapped it with some Electrical tape and Issue is gone. So try messing with the wires to your injectors...you never know.

 

Start car and remove one coil then replace. If the idle is rough while coil is removed, then the coil is good. Repeat exercise for each coil to identify the bad coil.

 

Ill check the wires soon!
Ive been trying to pull a coil! But it hasnt have misfire issues since this post. Only when it gets super colldd

It will all be thoroughly inspected this weekend !

 

The problem went away for a while but decided to come back today :'(

I was able to open the hood and pull the plug on the cylinder 4 ignition coil and it didnt get any worse. So I guess my coil os just bad!

 

Well I finally had time to mess with it. Thought I better buy a spark plug and try it first before dropping $60ish dollars for a coil. Ran rough for a few minutes then smoothed out. Drove like a maniac all of today trying to make it misfire and couldnt manage to do so. Fingers crossed I dont have any more issues. Also I noticed my idling rpms are about 150-200 lower than before. Could this mean the spark plug was bad and compensated by idling higher? Thus the loss of about 3 mpg? It was about 900 before and now is around 700-750

 

Im having both exact same codes. plan on replacing number 4 coil pack tomorrow.

 

Good luck with that! Be sure to let me know if it fixes your problem

 

So Far a New coil pack fixed mine.

 

Well unfortunately mine started misfiring again.. gonna switch two of the coils around and see if it gives me an error code in a different cylinder

 

From what i read i dont know why but they say supposed to change all 6 same time.

 

Well I put the suspected bad coil in the 2nd cylinder and sure enough the code said the misfire was now in the 2nd cylinder. So im going to autozone to pick up a new coil tomorrow and hopefully thay will be the last of it.

Yes ive heard that too. But the only reasoning behind it is that if theyre in the rear its a P.I.T.A. to have to take the intake manifold off and etc. Just easiwr easier to do all while youve got it open.

May not be entirely accurate^^
Im merely speculating. I have friends who replace them as they go with no issues. Technically itd be a good Idea to replace spark plugs while changing coils just because they're there. But it all depends on what type of person you are. "It aint broke so dont fix it" or "By the book"

 

^
OEM coils!!!!!

 

I really dont care if its oem or not at this point. I just need something to keep my car running. Theres not a single place around that has it in stock, and I fear that if I wait any longer ill be SOL. If in fact I have issues (CEL or w/e) ill take it back.

 

Those symptoms do sound like your coil is going bad. Get OEM coil or the P1320 will not go away. I might even have some DE-K coils still laying around.

 

I replaced it with duralast from auto zone.
No lights. No issues. No problems.

Actually one of the coils thats been in the car is also a duralast and its at least 2 years old.

 

I have the P1320 code (and P0505 for IAC) but do not have obvious misfires. Just changed the plugs a few minutes ago. Since my car idles smooth, just starts like hell, is there a chance that the IAC is causing the misfires and not the coils?

 

P0505 IACV and smooth idle ~ does not compute!

No, IAC will not cause misfires it just controls RPM's at idle. Replace coil.

 

Original equipment coils were bad. New coils from the dealer are revised (usually have a gray dot on them) and are fine. Any aftermarket coil is probably fine as well.

Difficult to find out which coil is bad, since malfunction is usually intermittent. Surefire way to rid 1320 code is to buy two new coils - one front and one rear. Swap out one front and one rear, clear code, drive for a few days. If code returns, swap next two, etc.

 

Ya, no joke, that is why I am hesitant to change anything quite yet. The car will not start when cold, I hold the accelerator for about 15 seconds and it will idle. Once it warms up, no starting issues at all. If I clear the codes while the engine is warm, the SES light stays off. Upon the next cold start, the engine will stall, and the light will come back on with both codes 505 and 1520.

 

Do you think the idle stumble due to bad IAC could be causing the 1320 code?

 

P.S. $92.50 for OEM Coil packs, special order.

 

I don't think it would be related. P1320 is illuminated only under the condition that the ignition signal in the primary circuit is not sent to the ECM during cranking or operation. Irregardless of what the IACV valve is doing, the coil would still be receiving power and sending a return ignition signal to ECM for verification no matter what the RPM controlled by the IACV is doing. Sounds to me like u got 2 problems not 1....

 

I thought so too, then the dealership made me doubt it. I have an appointment tomorrow, maybe we can figure something out.

 

That is pretty strange but a faulty or gunked up crank position sensor can cause hard starting conditions while still allowing it to run once it's actually started. But that doesn't explain the P0505 code. Lol.

 

Thank you for verifying my thoughts, I am going to run the FSM instructions on crank position sensor testing. Going to do it both warm and cold to see if I get different results.