Engine Ping on 91 Octane

Modshack · 11-11-2009, 02:28 PM

Quote:

Originally Posted by WhiskeyHotel

I'm really surprised the ECU lets any detonation occur - at least that's audible. I figured it would just back off the timing.

It should...Could be a malfunctioning Knock Sensor..

Rocketman · 11-11-2009, 06:19 PM

Thanks for all the input guys. I made an appointment for this Saturday to have the car checked out again. I figure I'll give the dealership that I bought the car from one more chance. I will insist on them running some diagnostics and see if they cant figure it out. If I'm not satisfied I'll go elsewhere. As for the noise, I have not ruled out the heat shield yet but I find it unlikely given that running an octane booster greatly diminished the metallic noise. This could always be the placebo effect but I pretty certain this is the case.

I'll try to keep you guys updated if I find out any new information. In the mean time feel free to chime in if you can think of any more causes or are experiencing the same issue. I would like to hear some input from some of our AZ members to see if they are experiencing the same thing. I know AZ is prone to running different blends of gasoline through out the year to cut down on emissions. I am curious if this could be the cause.

davidyan · 11-19-2009, 11:22 PM

Quote:

Originally Posted by Modshack

It should...Could be a malfunctioning Knock Sensor..

There could be some small delay before the knock sensor kicks in. It has to detect a ping before pulling back the timing.

kannibul · 11-11-2009, 10:08 AM

Quote:

Originally Posted by Rocketman

Hey guys, Ive been a long time lurker on this forum ever since I picked up my Z back in January. I decided I should probably go ahead and register as I have just started experiencing my first potential issue with the car. My apologies in advance for the long explanation below but I will try to explain the problem the best I can.

Recently I have noticed a slight engine ping while accelerating. The ping generally occurs under very light load (think typical city driving) between 1500-3000 rpm and tends to get more prevalent as the engine temperature rises. I have always run premium gas in the car (91 is the best you can get here in Phoenix) typically from Chevron or Shell so I'm not sure what to make of it. I took the car into the dealership last week hoping that the noise was just a loose heat shield. After inspecting the car the service manager took it for a drive and also diagnosed the noise as a slight engine ping. Confused, he instructed me to try running an octane booster as a troubleshooting step and report back to him. I have since tried this and noticed that the ping is nearly all but gone. Reverting back to regular 91 causes the ping to return.

My only thought is that this could be caused by either 1) crappy AZ gas or 2) a lean condition caused by bad O2 sensors. Before I take the car back to the dealer I was wondering if anyone else has experienced any sort of the same behavior? If not, any idea on what could be the cause? The car is completely stock.

Btw thanks for having me.

Find a gas station that doesn't put ethanol in their gas. See if that makes a difference.

CAN-ZED · 11-11-2009, 10:24 AM

Quote:

Originally Posted by Rocketman

Hey guys, Ive been a long time lurker on this forum ever since I picked up my Z back in January. I decided I should probably go ahead and register as I have just started experiencing my first potential issue with the car. My apologies in advance for the long explanation below but I will try to explain the problem the best I can.

Recently I have noticed a slight engine ping while accelerating. The ping generally occurs under very light load (think typical city driving) between 1500-3000 rpm and tends to get more prevalent as the engine temperature rises. I have always run premium gas in the car (91 is the best you can get here in Phoenix) typically from Chevron or Shell so I'm not sure what to make of it. I took the car into the dealership last week hoping that the noise was just a loose heat shield. After inspecting the car the service manager took it for a drive and also diagnosed the noise as a slight engine ping. Confused, he instructed me to try running an octane booster as a troubleshooting step and report back to him. I have since tried this and noticed that the ping is nearly all but gone. Reverting back to regular 91 causes the ping to return.

My only thought is that this could be caused by either 1) crappy AZ gas or 2) a lean condition caused by bad O2 sensors. Before I take the car back to the dealer I was wondering if anyone else has experienced any sort of the same behavior? If not, any idea on what could be the cause? The car is completely stock.

Btw thanks for having me.

I too have noticed this ping at low rpms, in 1st gear mostly, even more so in reverse, I always run 91 octane
I can get 94 octane here in Canada at 1 gas station(Sunoco), maybe ill try that to see if it makes a difference

j.arnaldo · 11-11-2009, 12:46 PM

I think you hit it right on the nose when you mentioned the O2 sensors. Are they ECU-controlled? Then have her hooked up to a Diagnostics Analysis computer; that should tell the tale of the ping. If the stealership can't diagnose it, they're the most deficient and inadequate stealership I've ever heard of! Good luck, dude. BTW, it's a crying shame that you don't have higher octane gas available in your area. Thank God, down here we have 93-octane Texaco with Techron, my only choice, 'xept in an emergency.

RCZ · 11-15-2009, 06:31 PM

2500-3000 rpm = heavy vibration from this engine. See if thats specifically when you are hearing it. I dont know if its a rattle thought because you say you are hearing single pings...no mods right?

This is going to be one of those things you need to datalog to see whats happening. If you dont see anything weird in the logs, then look for a mechanical issue. Does it do it when you rev at idle?

Rocketman · 11-15-2009, 10:40 PM

No mods, the car is completely stock.

The rattle occurs between 1500 and 3000 rpm. No rattle when reving in neutral or when accelerating hard. It only seems to happen under light throttle. I also payed attention to oil temperatures today as that's really the only thing we have to go by. It appears that it doesn't start to happen until the oil temperature reaches about 210-215F.

Modshack · 11-16-2009, 04:46 PM

Quote:

Originally Posted by Rocketman

No mods, the car is completely stock.

The rattle occurs between 1500 and 3000 rpm. No rattle when reving in neutral or when accelerating hard. It only seems to happen under light throttle. I also payed attention to oil temperatures today as that's really the only thing we have to go by. It appears that it doesn't start to happen until the oil temperature reaches about 210-215F.

A rattle and an engine Ping are two different things. Which is it? Or can't you tell?

Rocketman · 11-16-2009, 06:46 PM

Its a real thin metallic sound. The best way I could describe it is the sound that is made when you bog an engine just before stall. Is there a chance that this might be something other than pinging? So far nothing can be found that could be rattling underneath the car. My only thought would then be something internal. I know the transmission in these cars is generally pretty noisy but the sound usually doesn't appear until after the clutch is fully engaged.

370Zsteve · 11-16-2009, 07:27 PM

Quote:

Originally Posted by Modshack

A rattle and an engine Ping are two different things. Which is it? Or can't you tell?

Have to put an exclamation point on this...a ping is a very distinct sound, and to these ears anyway most vehicles I've heard pinging sound almost identical, from 4-cylinder to 8-cylinder cars. So, again, you do know a ping when you hear one, right?

And I have to ask, did the techs at the new dealer hear the noise?

Rocketman · 11-16-2009, 09:59 PM

I have to admit, I have never heard a pinging engine in person so i am a bit lacking in knowledge here. After driving the car today the noise definitely sounds more like a rattle. I listened to some youtube clips of pinging engines and it appears like pinging sounds more like someone shaking a spray can. The noise my car is making sounds more like a loose/vibrating heat shield. I crawled under the car again today and thumped around on a bunch of things. I could not find anything that could be rattling. Guess I'm at a bit of a loss here.

When I took the car into the dealership the tech could not hear the noise. I am assuming because the engine was cold by the time he took it for a drive (car sat for about an hour before he got to it). I ended up taking the service manager for a lengthy drive to get the car warm. He heard the noise and diagnosed it as an engine ping although I am not sure I trust his technical backround all that much.

FricFrac · 11-20-2009, 02:06 PM

I know on my car if I don't get into the throttle enough starting off from a light sounds like a diesel engine but it seems normal from the people I've talked to and I think its a function of the VVEL system. Sounds more like the valve train than pinging.....

ChrisSlicks · 11-20-2009, 02:16 PM

I wonder if the engine is actually tuned for 93 octane and it is having to retard the timing slightly for 91 octane? Would explain the noise, but I would expect to be hearing more complaints from the West Coast.

JSBZ · 05-14-2012, 12:38 PM

I will get pinging at moderate load if the engine oil is running high >210.
91 octane is the highest available here in CO without going to race gas.

11-11-2009, 06:19 PM	#2 (permalink)
Rocketman Base Member Join Date: Nov 2009 Location: Phoenix, AZ Posts: 12 Drives: 09 370Z Base 6sp Rep Power: 16	Thanks for all the input guys. I made an appointment for this Saturday to have the car checked out again. I figure I'll give the dealership that I bought the car from one more chance. I will insist on them running some diagnostics and see if they cant figure it out. If I'm not satisfied I'll go elsewhere. As for the noise, I have not ruled out the heat shield yet but I find it unlikely given that running an octane booster greatly diminished the metallic noise. This could always be the placebo effect but I pretty certain this is the case. I'll try to keep you guys updated if I find out any new information. In the mean time feel free to chime in if you can think of any more causes or are experiencing the same issue. I would like to hear some input from some of our AZ members to see if they are experiencing the same thing. I know AZ is prone to running different blends of gasoline through out the year to cut down on emissions. I am curious if this could be the cause. wideglideleon likes this.

11-11-2009, 12:46 PM	#6 (permalink)
j.arnaldo Banned Join Date: Oct 2009 Location: Puerto Rico Posts: 937 Drives: Nissan 350Z, 2004 Rep Power: 0	I think you hit it right on the nose when you mentioned the O2 sensors. Are they ECU-controlled? Then have her hooked up to a Diagnostics Analysis computer; that should tell the tale of the ping. If the stealership can't diagnose it, they're the most deficient and inadequate stealership I've ever heard of! Good luck, dude. BTW, it's a crying shame that you don't have higher octane gas available in your area. Thank God, down here we have 93-octane Texaco with Techron, my only choice, 'xept in an emergency. Last edited by j.arnaldo; 11-12-2009 at 12:28 PM.

11-20-2009, 02:06 PM	#13 (permalink)
FricFrac A True Z Fanatic Join Date: Dec 2008 Location: Victoria, BC Posts: 1,481 Drives: 370Z 300ZX 280ZX 240 Rep Power: 229	I know on my car if I don't get into the throttle enough starting off from a light sounds like a diesel engine but it seems normal from the people I've talked to and I think its a function of the VVEL system. Sounds more like the valve train than pinging..... __________________ '09 370Z - '93 300ZX Vert - '83 280ZX - '83 280ZXT -'81 280ZXT stroker - '72 240Z - Stillen CBE, HFC, G3, Grounding Kit, Sways // Swift Spring // H&R 15mm // 5% Tint // Clear Bra //

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11-15-2009, 06:31 PM	#7 (permalink)
RCZ A True Z Fanatic Join Date: Nov 2008 Location: Miami Posts: 6,403 Drives: '09 370Z Rep Power: 1119	2500-3000 rpm = heavy vibration from this engine. See if thats specifically when you are hearing it. I dont know if its a rattle thought because you say you are hearing single pings...no mods right? This is going to be one of those things you need to datalog to see whats happening. If you dont see anything weird in the logs, then look for a mechanical issue. Does it do it when you rev at idle?

11-15-2009, 10:40 PM	#8 (permalink)
Rocketman Base Member Join Date: Nov 2009 Location: Phoenix, AZ Posts: 12 Drives: 09 370Z Base 6sp Rep Power: 16	No mods, the car is completely stock. The rattle occurs between 1500 and 3000 rpm. No rattle when reving in neutral or when accelerating hard. It only seems to happen under light throttle. I also payed attention to oil temperatures today as that's really the only thing we have to go by. It appears that it doesn't start to happen until the oil temperature reaches about 210-215F.

11-16-2009, 06:46 PM	#10 (permalink)
Rocketman Base Member Join Date: Nov 2009 Location: Phoenix, AZ Posts: 12 Drives: 09 370Z Base 6sp Rep Power: 16	Its a real thin metallic sound. The best way I could describe it is the sound that is made when you bog an engine just before stall. Is there a chance that this might be something other than pinging? So far nothing can be found that could be rattling underneath the car. My only thought would then be something internal. I know the transmission in these cars is generally pretty noisy but the sound usually doesn't appear until after the clutch is fully engaged.

11-16-2009, 09:59 PM	#12 (permalink)
Rocketman Base Member Join Date: Nov 2009 Location: Phoenix, AZ Posts: 12 Drives: 09 370Z Base 6sp Rep Power: 16	I have to admit, I have never heard a pinging engine in person so i am a bit lacking in knowledge here. After driving the car today the noise definitely sounds more like a rattle. I listened to some youtube clips of pinging engines and it appears like pinging sounds more like someone shaking a spray can. The noise my car is making sounds more like a loose/vibrating heat shield. I crawled under the car again today and thumped around on a bunch of things. I could not find anything that could be rattling. Guess I'm at a bit of a loss here. When I took the car into the dealership the tech could not hear the noise. I am assuming because the engine was cold by the time he took it for a drive (car sat for about an hour before he got to it). I ended up taking the service manager for a lengthy drive to get the car warm. He heard the noise and diagnosed it as an engine ping although I am not sure I trust his technical backround all that much.

11-20-2009, 02:16 PM	#14 (permalink)
ChrisSlicks A True Z Fanatic Join Date: Mar 2009 Location: North East Posts: 6,203 Drives: 09 370Z Sport M6 Rep Power: 654	I wonder if the engine is actually tuned for 93 octane and it is having to retard the timing slightly for 91 octane? Would explain the noise, but I would expect to be hearing more complaints from the West Coast.

05-14-2012, 12:38 PM	#15 (permalink)
JSBZ Base Member Join Date: Jun 2009 Location: Colorado Posts: 56 Drives: 09 370Z T/S 6MT Rep Power: 16	I will get pinging at moderate load if the engine oil is running high >210. 91 octane is the highest available here in CO without going to race gas.