Severe Pinging

[Professor`]

For the last few months my check engine light has been on, its throwing the lean codes, Ive tried several things and i cant resolve this problem, i replaced the intank filter, MAF and i replaced all the upper intake gaskets, iam still getting severe and i mean really bad pinging, almost undriveable, it starts around 1800rpm and up to 3500 , i dont know what else to do.Also when i add gas its like 50 times worse for abit till i drive it around.i own a 2000 Maxima, just a intake, exhaust, nothing major.Please help me figure out what is causing this.

[Eikon]

Fuel injectors might be going on you.

Try running some injector cleaner through.. perhaps even a seafoam treatment. You might get some improvement by doing this. It's a cheap thing to try at least.

Consider replacing the fuel injectors. If you are running lean, it could be from bad or stuck injectors that are just not getting you enough fuel.

[NutriaforBreakfast]

Test the knock sensor and check the timing

[Professor`]

Test the knock sensor and check the timing

wouldent a bad knock sensor throw a code ?iam only getting P0171 & P0174

[NutriaforBreakfast]

Maybe, but it sounds like you have predetonation in your engine,very serious. Would do anything to resolve this

[Professor`]

Maybe, but it sounds like you have predetonation in your engine,very serious. Would do anything to resolve this

i know its predetonation, its severe if i try to go up a hill, i can hear the pistons rattling like crazy, i have to go really slow up a hill so it dont ping.iam at wits end trying to solve this.

[MinisterofDOOM]

Well, the problem has to be that either the engine isn't corrently adapting to prevent knock, or it isn't ABLE to because the knock is outside it's adjustment parameters. So either you have bad knock sensors, or you have something like a leaky injector as eikon suggested that's causing detonation the engine can't compensate for. Could also be a sensor issue (like MAF) or a seriously, horrendously dirty air filter or another air restriction that's causing the car to run very very rich.

[Professor`]

Well, the problem has to be that either the engine isn't corrently adapting to prevent knock, or it isn't ABLE to because the knock is outside it's adjustment parameters. So either you have bad knock sensors, or you have something like a leaky injector as eikon suggested that's causing detonation the engine can't compensate for. Could also be a sensor issue (like MAF) or a seriously, horrendously dirty air filter or another air restriction that's causing the car to run very very rich.

Iam going to test the knock sensor tommorow, The maf and air filter i are new so thats not the issue, also its not running rich, its running very lean. Ill post my findings about the knock sensor and go from there. someone told me it could be the O2 sensor back by the firewall, what are your thoughts on that ?

[NutriaforBreakfast]

Sounds like the engine timing is too far advanced. Have you checked this?

[Professor`]

Sounds like the engine timing is too far advanced. Have you checked this?

Timing is good, i added 2 bottles of fuel injector cleaner to see if anything happens,so far so bad.....

[Professor`]

I just tested the knock sensor, i found a open circut, So i need to replace the sensor............................ pain in arse because i have to remove upper and lower intake manifolds..........

[asand1]

Does the 2000 have EGR, or did you delete your EGR? Having a plugged up EGR or deleted EGR will cause higher combustion chamber temps. Do you burn ANY oil? Carbon deposits are the result of burnt oil and will plug up EGR or deposit directly on piston heads or Combustion Chambers and act like a glow plug. How hot are your plugs, you could try a colder range. Don't know the part #s off the top of my head, but I know where I might get them. A bad knock sensor will cause the ECU to fully retard timing, so Bad KS wont be likely. Use a can of carb/brake cleaner and check for vacuum leaks around your manifold and intake plumbing. that would cause a lean condition and detonation.

[Professor`]

Does the 2000 have EGR, or did you delete your EGR? Having a plugged up EGR or deleted EGR will cause higher combustion chamber temps. Do you burn ANY oil? Carbon deposits are the result of burnt oil and will plug up EGR or deposit directly on piston heads or Combustion Chambers and act like a glow plug. How hot are your plugs, you could try a colder range. Don't know the part #s off the top of my head, but I know where I might get them. A bad knock sensor will cause the ECU to fully retard timing, so Bad KS wont be likely. Use a can of carb/brake cleaner and check for vacuum leaks around your manifold and intake plumbing. that would cause a lean condition and detonation.

When i had the intake off and replaced all the gaskets as i stated in first post,i cleaned the egr tube, it was blocked, I dont burn oil, i use the NGK 7090 plugs.I did the spray around the intake and i had no issues there.

[Professor`]

So i was reading threads and found that a 550k resistor is a temporary fix for the knock sensor, is this advisable? I got the resistor, i only want to do this because of the high cost of the sensor and its location, i just need time yet before i can do this.

[asand1]

So i was reading threads and found that a 550k resistor is a temporary fix for the knock sensor, is this advisable? I got the resistor, i only want to do this because of the high cost of the sensor and its location, i just need time yet before i can do this.

WRONG, its 470K, color code yellow, violet, yellow, gold. Radio Shack # is 271-1133. package of 5 is only $0.99. Disconnect the KS sub-harness near the LIM/UIM joint, and insert in female terminals. Then clear Codes.

I am currently running this "mod" cause I'm cheap. It does detonate with Regular, but I haven't heard anything running Premium.

HOWEVER, you need to find out why you are pinging. A bad KS will retard your timing, and in that case you would then have NO pinging. Your pinging is caused by a problem with the engine NOT the KS.

[Professor`]

WRONG, its 470K, color code yellow, violet, yellow, gold. Radio Shack # is 271-1133. package of 5 is only $0.99. Disconnect the KS sub-harness near the LIM/UIM joint, and insert in female terminals. Then clear Codes.

I am currently running this "mod" cause I'm cheap. It does detonate with Regular, but I haven't heard anything running Premium.

HOWEVER, you need to find out why you are pinging. A bad KS will retard your timing, and in that case you would then have NO pinging. Your pinging is caused by a problem with the engine NOT the KS.

Thanks for the info, i tried this setup and i still got pinging so iam going to rule out the KS as the main issue, i really dont know what else to do. iam just going to install a new fuel pump, fuel damper and fuel pressure regulator, if it still does it ill move on to the injectors, and if it still does it ill set it on fire.

[Professor`]

I applied connector protector dielectric grease to the MAF harness, Fuel Pump Harness, and KS Harness, there is a mild improvemnt but its still there, Last night i stared the car, waited about 1 min, put her in drive and went to pull out and she fell on her face, backfired out of the intake 2 times and shut off, she started back up fine and been driving fine since, what gives ?????????????Any other idea's ? 14 sep Nissan techs said MAF and low fuel pressure, and where i work i asked one of the mechanics who is very good, first words out of his mouth where MAF

[asand1]

You could try cleaning your MAF.

[Professor`]

Instead of cleaning the MAF for the 50th time i just got a new one and it fixed everything, feels like a new motor. the one i had was defective.

[Nissan3m]

I just tested the knock sensor, i found a open circut, So i need to replace the sensor............................ pain in arse because i have to remove upper and lower intake manifolds..........

I am having a similar issue with my 2000 I30, did you replace the KS in addition to the MAF? I have cleaned my MAF several times as well as replaced the plugs.