How To Stop Pre-Detination Rattle?

[Azca]

So if the timing is advanced it knocks, what if you retard it back one or two degrees? I am at 3 now am wondering if I should try going further back. What is the hazard in doing this?

 

[LFD2037]

Your "estimate"? Did you actually check the engine timing per the FSM?

I used a timing light. I used the jumper in the diagnostic box. Timing measured, with the light, was 3*. I advanced it to 7* (there's only a mark for 3,10 and 15 and I put it between 3 and 10) .
Your saying my timing could actually be off even though the timing light showed between 6 and 7*?

 

[94SRUNNER]

I interpreted you post incorrectly. It's sounds like your timing is set correctly from that stand point.

Have you considered pulling the distributor to see if it is a tooth off?

 

[LFD2037]

I interpreted you post incorrectly. It's sounds like your timing is set correctly from that stand point.

Have you considered pulling the distributor to see if it is a tooth off?

If it was a tooth off wouldn't I have more trouble than just pinging on take-off? This is my daily driver and I've put about 5K miles on it with it like this. It's runs 100% normal otherwise. I've read where people had their timing off 1 tooth in each direction and it wouldn't hardly even run.

 

[Reelitchy]

Sorry -You used a jumper and set you timing - yes even a tooth off you can still get the timing in the right place. I'm thinking the whole tooth off is no big deal

 

[Azca]

Just got back from running around with the new colder plugs... still pinging . So based upon my photos before, as the old plugs appear to be oil/carbon fouled, it must be the carbon build up right?

 

[LFD2037]

Azca,
I'd bet yours is from carbon buildup. Google, about and how to use, MCCC or Mopar Combustion Chamber Cleaner. It's $9 at my local Dodge house.

 

[Funner]

Have you reset your timing back to 3 since the start of this thread and/or after you replaced the O2 sensors?

 

[Azca]

Timing is at 3, I have not rechecked it after the O2 sensors however. I have reset the ECU but will go back and check timing with the light.

 

[LFD2037]

Have you reset your timing back to 3 since the start of this thread and/or after you replaced the O2 sensors?

No. It did it with good O2's at 3* before so I'm sure it'd still do it. If I owned a timing light I would just change it back but I don't own one and they don't rent them anywhere around me.

 

[NLXTACY]

No. It did it with good O2's at 3* before so I'm sure it'd still do it. If I owned a timing light I would just change it back but I don't own one and they don't rent them anywhere around me.

$40 at PepBoys

 

[LFD2037]

Meh. I've changed the timing once in my life, a couple months ago, and don't really have any intentions to ever change it again except for this instance. I'll just borrow one from a guy at work next week. It's free, I'm in no hurry (I know it won't change this situation) and he has several and doesn't mind letting me borrow one for 5 minutes.

 

[NLXTACY]

Meh. I've changed the timing once in my life, a couple months ago, and don't really have any intentions to ever change it again except for this instance. I'll just borrow one from a guy at work next week. It's free, I'm in no hurry (I know it won't change this situation) and he has several and doesn't mind letting me borrow one for 5 minutes.

Its not about changing it. Its about checking it anytime you need to without posting on a forum that you don't have one. But

 

[LFD2037]

Its not about changing it. Its about checking it anytime you need to without posting on a forum that you don't have one. But

I borrowed my neighbors timing light. Timing was @ +6 to 7*. Changed it to +3*. Same situation & pinging. So to reiterate:
pings @ low RPM (<1,900) under light load or high RPM (> 3,500) @ WOT
only when ambient temp is >85* & engine is >180*
not a timing issue
no vacuum leaks
new cap, rotors, air filter, plugs, oil, O2's
no codes (no check engine light)
doesn't ping w/premium fuel (92-93 octane)
'cleaned' intake, injectors & cylinders w/MCCC

Since it's not timing, carbon or vacuum you'd assume it'd be a lean condition. From what I've read on what my short trim, long trim, & both O2's are displaying on my Ultragauge it's not running lean, it's running properly. After reading many FZJ80 threads on low RPM pinging, I'm really starting to think I'm pissing in the wind trying to find a conclusion to this.

 

[LFD2037]

I borrowed my neighbors timing light. Timing was @ +6 to 7*. Changed it to +3*. Same situation & pinging. So to reiterate:
pings @ low RPM (<1,900) under light load or high RPM (> 3,500) @ WOT
only when ambient temp is >85* & engine is >180*
not a timing issue
no vacuum leaks
new cap, rotors, air filter, plugs, oil, O2's
no codes (no check engine light)
doesn't ping w/premium fuel (92-93 octane)
'cleaned' intake, injectors & cylinders w/MCCC

Since it's not timing, carbon or vacuum you'd assume it'd be a lean condition. From what I've read on what my short trim, long trim, & both O2's are displaying on my Ultragauge it's not running lean, it's running properly. After reading many FZJ80 threads on low RPM pinging, I'm really starting to think I'm pissing in the wind trying to find a conclusion to this.

Just replaced fuel filter & fuel pump filter(sock) & no difference. I've now done every single thing possible to eliminate the pinging & nothing has changed it EXCEPT higher fuel octane. I'm not going to pay $.40+ per gallon to keep it from pinging. That's over $400/yr. Not worth it to me. I'm sure it's causing damage but people have said they've dealt w/it over 5 years. That's $2,000 for a new motor!
I'll deal w/the pinging & drive it till it blows up I guess.

 

[Funner]

Just replaced fuel filter & fuel pump filter(sock) & no difference. I've now done every single thing possible to eliminate the pinging & nothing has changed it EXCEPT higher fuel octane. I'm not going to pay $.40+ per gallon to keep it from pinging. That's over $400/yr. Not worth it to me. I'm sure it's causing damage but people have said they've dealt w/it over 5 years. That's $2,000 for a new motor!
I'll deal w/the pinging & drive it till it blows up I guess.

Quiter

 

[elhombre]

Carbon around the fire ring/ top of psitons. The carbon remover stuff they sell ain't going to take off the carbon put on over the span of 10s of thousands of miles of driving. Buy the head gasket and assorted gaskets, and fix it on your own time.

It does sound funny when a Cruiser owner complains about the cost of putting fuel in our trucks.........

 

[LFD2037]

Carbon around the fire ring/ top of psitons. The carbon remover stuff they sell ain't going to take off the carbon put on over the span of 10s of thousands of miles of driving. Buy the head gasket and assorted gaskets, and fix it on your own time.

It does sound funny when a Cruiser owner complains about the cost of putting fuel in our trucks.........

I've never complained of putting gas in it or how poor the fuel mileage is. I complained that it'd be even more than it already is!

 

[Reelitchy]

Hey, was wondering if you got a chance to blow through the FP regulator return line to see if it is clogged or pinched. Easy quick
Check

 

[LFD2037]

Hey, was wondering if you got a chance to blow through the FP regulator return line to see if it is clogged or pinched. Easy quick
Check

I have not. Do I just disconnect @ FPRegulator & blow in it w/the vehicle not running?