P0325 and p0300 2 year battle

[Rustain]

I have a 99 Maxima with 78,000 miles about 2 years ago it started "pulsing" mainly when it was in drive at stop lights and such. When I put it in neutral it doesn't didn't do it. Took it in and no body could figure out was was wrong. Then it started pulsing/mis-firing when I accelerated typically around 40 mph. Finally a check engine light came on, so I took it in again. This time it came up as a 3rd cylinder misfire. However, the mechanic wasn't sure if it was the coil or the fuel injector, so he switched the 2nd and the 3rd coil. It continued to misfire when stopped, while in drive. I did notice that if I watch the rpms, they seem to drop to about 800 and then it misfires. I then took the car into a mechanic who couldn't figure it out and then to a dealership who charged me $70 to tell me the code that came up was a multi-cylinder misfire, but didn't know what was wrong. Now I just went to Autozone and had them pull codes and it came up as a P0325 and a P0300. I thought that knock sensors in Nissan's didn't control the engine, (which is unlike other cars) so anyone have thoughts or insight as to what could be wrong. I am tired of taking the car in to people and paying them to say, "We just couldn't pinpoint the issue, if it does it again bring it back in".

[99redmaxSE-L]

Originally Posted by Rustain

I have a 99 Maxima with 78,000 miles about 2 years ago it started "pulsing" mainly when it was in drive at stop lights and such. When I put it in neutral it doesn't didn't do it. Took it in and no body could figure out was was wrong. Then it started pulsing/mis-firing when I accelerated typically around 40 mph. Finally a check engine light came on, so I took it in again. This time it came up as a 3rd cylinder misfire. However, the mechanic wasn't sure if it was the coil or the fuel injector, so he switched the 2nd and the 3rd coil. It continued to misfire when stopped, while in drive. I did notice that if I watch the rpms, they seem to drop to about 800 and then it misfires. I then took the car into a mechanic who couldn't figure it out and then to a dealership who charged me $70 to tell me the code that came up was a multi-cylinder misfire, but didn't know what was wrong. Now I just went to Autozone and had them pull codes and it came up as a P0325 and a P0300. I thought that knock sensors in Nissan's didn't control the engine, (which is unlike other cars) so anyone have thoughts or insight as to what could be wrong. I am tired of taking the car in to people and paying them to say, "We just couldn't pinpoint the issue, if it does it again bring it back in".

what you explained was wrong with your car is EXACTALLY the type of shit my maxima used to do, mine also a 99. finally my car couldnt take any more and HAD to go to the shop ( my rents were resiliant to take it in ) and it was my ignition coils that had gone bad. after they were replaced, my maxima has run perfect.

[Nahkapohjola]

Originally Posted by Rustain

... I am tired of taking the car in ...

I bet the ppl lookin at these cars without problem are tired too. What can they do if the car is behavin perfect? Its a design flaw which serves well in the new cars selling buziness...

New filters, plugs & coilpacks are part of 'normal' ol car tuneup. Ol car? Yes, after 3yrs its old oxidized junk - maybe. Do not think stealer$hips or ANY shop have will or iq to do anythin about it; its owners responsibility.

Check out the revenge of CDC computer scientists:
clic on http://www.cardomain.com/ride/748507/14

[Rustain]

"What can they do if the car is behavin perfect? Its a design flaw which serves well in the new cars selling buziness..."

Let me tell you a little bit about my interaction with the dealership. I took the car in and told them that I had already pulled codes and knew that it was coming up as a multi-cylinder misfire and that if all they were going to do was pull codes then don't worry about it. They reassured me, "No we should be able to isolate what the issue is".
Now this is one of those nice dealerships with a glass wall that looks into the shop from the waiting area. I then watched them pull my car in, it set for 20 minutes, then someone walked up pulled codes and walked way. It set for another 20 minutes then it was pulled around and I was given a bill for $60 (a hour of labor). So as for what they could have done, hmmm, perhaps driving it more than a 100 ft? Perhaps hooking it up the a computer reader to check what all the sensors are reporting? I don't think pulling codes is all that they could have done.

[rather_b_boatin]

I've found the $tealer$hip$ here (S.E. Connecticut) generally full of $hit. Last time CEL illuminated I brought it down after reading code myself (O2 sens. high voltage) assuming they would replace it under cal. emissions warranty, they told me (for $90) that the 2 rear O2 sens. needed replacement and ECU needed re-programing. Total cost $611, tax, parts, labor, diagnostics. WTF?? I jumped on here and Nahk told me sounded fishy, replaced affected O2 sens. myself and all seems fine 1600 miles later. Total cost DIY $195 (90 to stealership) They have a special place in my heart!

[hueroloco]

rustain,
i have a 2000 maxima in the shop right now with the same symptoms. I felt the "pulsing", mostly when I hit the gas, not so much at a stop sign. I didn't have any way to check fuel pressure. I have a $400 set of frickin fuel pressure testing stuff, but apparantly I need more cuz I can't check it on this car. So anyway, I checked the fuel pump itself with a low amp probe.

every time I felt the "pulsing" the fuel pump waveform would get all jagged. So I'm replacing the pump.

I'll let you know what happens, but it might be awhile. I go on vacation tomorrow night.

Other possibilities:
MAF sensor can cause these symptoms
I looked up the symptoms and read that the o2 sensors can cause similar symptoms and even cause a no-start.

Anywayz, I'll keep you posted

[Nahkapohjola]

Originally Posted by rather_b_boatin

... Total cost $611, ... Total cost DIY $195 (90 to stealership) ...

Most shops are at total loss with two simultaneous electronic problems; even one. Some keep charging, others dont want to see ya... So what can a non DIY -person do?
- buy a new car, keep until warranty ends
- keep ol' - only if a small shop with one intelligent serviceman is found

Even the factory service manuals are at loss: for one idiot fuse problem these insist for one day troubleshooting chart crawl through. Impossible.

Arrogant stealerships have always been like this: best I know was one Volvo stealership charging 8 (eight) hours for a turn signal problem. Problem Solution: press a button! (=the cause was a halfway -pressed hazard light button). And this was on the ol good relay -age, 1985...