01 pathfinder 3.5 se code 1320 engine random misfire

[jclaxcoach]

poped a code a few weeks back and took it to autozone to read the code.... 1320I was told it just could be bad gas or a fouled injector. I followed the advice to try fuel injection cleaner. two cans and 20 gal. of gas later the light is back and the same code (1320). New advice from a different person (mechanic)...... A can of Seafoam through a vacuum line to really clean things up and change the plugs. Here is the problem:1. I am worried about doing damage by unloading a whole can of seafoam through the vacuum line.2. Without a manual I can't see the plugs and therefore can't get to them.I have done plugs and wires, cap and rotor stuff to older model cars but this is a bit puzzling. Can anyone help with advice or a bookmark to a diagram?I ordered a Haynes book that will be on its way next week and will be helpful with testing the coils which I think may be the next step.

Any help will be appreciated.

[5upra]

just change the plugs first to see where you are at...do a search for plug change on the web.

[driftingmy240sx]

p1320 is a ignition primary signal fault code. the only way to properly correct it is to replace all 6 coils. sorry for the expensive news, and make sure you get NISSAN coils not aftermarket as they will go bad quickly.

[jclaxcoach]

Ouch. Are you sure? I will be trying to seafoam and change plugs then see what happens.

[driftingmy240sx]

yes i am sure you need to replace the coils. i am a nissan master tech adn this is a normal problem with the pathfinder adn maxima's

[jclaxcoach]

Seafoamed a half a can into the vacuum lines, ran it hard then changed the plugs. the plugs that came out were at about .80 gap on all 6, so i guess it needed plugs anyways. still reading a p1320 misfire after clearing the code. Help

80,000 miles

Is there any way to check the coils before changing all 6? Could there be any other solutions? This is very frustrating after changing 3 of 4 O2 sensors, maf sensor and i think camshaft position senssor in the past. I never had so many sensor problems on a car before. Any help is appreciated.Thanks.

[driftingmy240sx]

sorry man but the code p1320 is "igntion primary signal fault" the only component on the engine that is a primary ignition item is the coils. the coils are a common failure (at least at my sealership), mafs commonly fail on nissans also. the cam or variable timing control sensors go bad normally then oil varnish or sludge starts to build up in the timin case.

[boriquaS13]

I am also a master technichian and as driftingmy240sx said for that particular code replacing all the coils is the only repair. Sorry for the bad news.

[NissanManager]

p1320 is a ignition primary signal fault code. the only way to properly correct it is to replace all 6 coils. sorry for the expensive news, and make sure you get NISSAN coils not aftermarket as they will go bad quickly.

I will second this, I have many people trying to replace just one coil, which is the wrong thing to do even after time because they will just be back to do others soon after. Sad thing is too if all 6 are not replaced you could have the original one that was bad go out again. This can be particularly annoying when people are having their after market warranty repair their vehicle because they will only do one at a time. There is a TSB on the matter but I believe it is only on the Maxima. goodluck!

[jclaxcoach]

This may be a stupid question but what is a TSB?

[NISTECH]

Also a nissan master tech. Sorry to say if the only code you got is the 1320 your pretty much stuck with replacing all 6 coils. However if you have a single misfire code, you may have nailed which cyl is causing the problem. I have had a great deal of success when replacing the cyl that threw the misfire code. But this is not a 100% of the time fix. Some times there will be more then one coil causing the 1320 code but only one of the coils fails for the required 20secs to throw the misfire code. The 1320 code sets the second it does not see the ignition fire signal as it is a comprehensive code[open or short]. Misfire codes are moniter codes which means it waits and sees to make sure before it throws a code. As Nissan Manager said sometimes it ends up needing all 6 even with the single codes.

[Q45tech]

When Nissan went to integrating the swtching transistor into each coil instead of the earlier method of a separate ignitor module feeding 3-4 coils the cramped space caused many heat related problems.

Pretty common across all Brands and models ...............coil failure just after warranty. Ford, GM, Audi/Volks, BMW

Amazingly the 90-95 Q45 had separate ignitors on each bank and coil on plug failure is almost nonexistent even at 300-400,000 miles. Big hunky coils and a big expensive ignitor holding 4 well heat sunk switching transistors ............... no buget constants here and zero failures.

You might find this amusing: http://forums.audiworld.com/a4...phtmlh ... blems.html

When you study GM/Delco spec sheets on their coils they show a graph vs temp vs life and they only warranty the coils for 70k mile equivalents hours at 40 mph. {{ 2000 hours of use}} Perfectly designed to fail.

[jclaxcoach]

After some discussion with my local dealer, the most honest answer I can live with is to keep driving the car to hope for a cyl misfire and change that coil. I also was told that in their experience the maxima generally needs all 6 coils when this problem occurs BUT, the pathys have had good results when you can determine a single cyl misfire. I have about 6 months to drive before inspection will dictate I need to take action. My next question is if I can get to the cyl misfire to occur, will this render my vehicle disabled or do damage when it happens? Will a conservative approach cost me more than the 6 coils?

[boriquaS13]

TSB= Technical Service Bulliten.

[dr]

I pulled my coils and tested them with an ohm meter and got a consistent reading on all coils of 1.5 k ohms which 'seems' to be within spec. I assume from your comments earlier that the resistance test is not definitive for determining whether the coil is bad or not. Is there a test that can be run on the coils to find out if they have failed?

[jclaxcoach]

I may be wrong about this but my feeling is that when the coils are tested cold they my not indicate a problem........ Again this is just a guess but the coils that become marginal start to have problems when they are in the engine compartment and getting some heat. Unfortunately I can't really test this theory and will have to wait till there is some real coil failure and I get a cyl misfire code. In my case the ses light has come on then turned itself off...... now it is back on but has yet to cive me a cylinder misfire. I contine to drive with the light on and am still waiting for a coil failure to present itself.

[Q45tech]

That's the problem the coils don't fully fail they usually just don't create enough voltage to fire most or all the fuel under certain conditions thus random misfire.

They make fairly exotic equipment which can monitor the exhaust sound/pressure to narrow down WHICH pulse of exhaust is weak.

They make coil extension to add a short piece of spark plug wire that can be monitored for voltage and waveform.

Finding educated automotive lab engineers who can use and evaluate these signals is beyond most dealers so they don't buy the equipment.

You can acquire the equipment and learn how your self, but buying the coils would be cheaper.

http://www.picotech.com/auto/a....htmlh ... /w....html