Need help w/ spark knock

[Pathy24]

2001 pathfinder 149,000 miles

Have bad spark knock! Hooked it up to my reader and both camshaft sensors were bad.p1140 and p1145first time anything has been replaced on the car besides brakes and oilJust replaced them and codes are gone but still have the spark knock.

Occurs while accelerating under load.

Stopped by a local shop today and they hooked up their pc to it.They said the front o2 sensors were acting sluggish while rev the engine.

I checked them with fluke meter and the one reads 7 ohms and the other 6 ohms, the spec for these are 2.3-4.3 ohms.

Could this be the issue..also check engine light is not on?

Timing angle was 16 degrees which is in spec.

Could it be an ignition coil or spark plugs.just chaged the plugs last year.what about knock sensor?

first time post.Thanks!

[Issac]

Hi I am don't have a lot of experience on codes so can't help there. But check air filter, and mass air sensor for being dirty. Clean throttle body also.

Run premium also in winter and maybe Heet-some more experienced have said.

Some Techron in a half tank, or even better Bk44, or is it BG44 fuel system cleaner. You can read about that in q45 forums by searching.

Good luck.

[Pathy24]

uPDATE!

new code showed up this morning p0171 --system too lean

[Issac]

all the more reason to do above.

[Pathy24]

i just pulled out the maf sensor and it looks dirty what should i clean it with?

[Pathy24]

i cleaned the sensor and for the first mile no spark knock. Then it came back any ideas?

[Issac]

well i can keep trying to help. It is quite possible that it is Heat that could be causing a problem. Lean mixture makes heat, clogged or dirty radiator can generate heat, shoot maybe even water pump effectiveness (this I don't know for sure).

You might rest your computer by disconnecting both positive and negative for a few minutes, and ginving it an hour to adjust afterward.

If you clean the dirt out of the front of your radiator, which mine had a lot when I got it (you remove top cover to gain access), be careful not to spray high pressure and smash down your radiator channels.

You might flush also.

But again I do not know ECU's so you need someone elses advice on that. This cleaning and maintainence is regular good things to do anyway, and easy.

Bleed off radiator air bubbles as showin in manual by pulling little rubber vent cap hose.

[Pathy24]

i'm now getting p0100 and unable to even drive 10 yards without it shutting off.

dealer wants 560 bucks for a new mass air sensor and 100 to reprogram.

wtf

i'm going to check out some salvage yards first.

[timmack]

shouldnt need to be reprogrammed as far as i know, id try to clean it first. CRC makes a good cleaner and there are several good posts here on how to do it right, plus i think theres one or 2 that tell you about a maxima MAF fitting right up and clearing up the problem, and the maxima MAf is a ton cheaper than the one for pathy/Q.

[timmack]

zerothread?id=311862

zerothread?id=326080

zerothread/270549

[Pathy24]

thanks for the awesome info guys!!!

i'm thinking about trying the maxima switch

[Pathy24]

i just downloaded the 01 maxima and 01 pathfiner factory service manualsi compaired the specs on the mfc , the pages are completely identical.i'm going to pick the part up tomorrow and i'll let everyone know how it goes.

and just to be safe i downloaded the 01 frontier spec for the mfc and completely different how it should be.

[timmack]

just because the MAF is still expensive, id pick up a can of cleaner and clean the heck outta the old one just to try before you go out and buy the new MAF. ya never know. a $5 can of cleaner might be all it needs.

[Pathy24]

picked up the maxima mfc from the dealer for 70 bucks they looked at me like i was crazy, the techs came out to listen to what i was going to try, they want me to call them tomorrow if it works...anyway , fit right in no problem

crossed my fingers and started it up, at first it was idling at 3 grand, then over about 10 minutes it gradually lower and stayed at 700rpm, took it for a ride....Its like it was new...even better. Spark Knock is GONEthe acceleration is unbelievable and the engine is really queit.

I don't remember it ever driving so nice, I actually have to re-adjust to shifting (mt).it must of been a problem for awhile and never noticed it going.

on another note. .... 8 months ago i put a K&N filter on it......did it cause the mfc to fail????

Kuddos to whoever found this fix.. unbelievable

[timmack]

good to hear it worked, and yea there have been numerous posts on here referring to the MAF not liking the oil that you have to use with the k&n.

[Chris92SE]

picked up the maxima mfc from the dealer for 70 bucks they looked at me like i was crazy, the techs came out to listen to what i was going to try, they want me to call them tomorrow if it works...anyway , fit right in no problem

crossed my fingers and started it up, at first it was idling at 3 grand, then over about 10 minutes it gradually lower and stayed at 700rpm, took it for a ride....Its like it was new...even better. Spark Knock is GONEthe acceleration is unbelievable and the engine is really queit.

I don't remember it ever driving so nice, I actually have to re-adjust to shifting (mt).it must of been a problem for awhile and never noticed it going.

on another note. .... 8 months ago i put a K&N filter on it......did it cause the mfc to fail????

Kuddos to whoever found this fix.. unbelievable

I saw your other post in the "knocking.." thread I posted in.

It's possible your Pathy might have some other issues. Mine had only the lean bank code all along and it has been running fine since then (that was in Sept or October).

There have been several people that I have read about using the Maxima MAF and I can't recall anyone having side effects of it.

As for the K&N, I removed mine and went back to stock paper filter. First, I noticed that the filter is REALLY close to the MAF sensor. Second, I talked with a mechanic that told me it's possible that the oil from the K&N harmed the sensor.