With summer the "ping" returns...

[dd74]

My engine reached 220 to 230 degrees today in bad traffic, and after punching it on an uphill on-ramp, the 3.0 pinged from about 4K to 6K, before I let off. This happened in third and fourth gear under an uphill load. Later, when the motor cooled off to about 210 degrees, and while on flat ground, the same 4 to 6,000 RPM punching yielded no pinging.

I figure it's the heat, though I may be wrong. I have - at least - a trombone cooler on my engine, but plan to install a Carrera cooler later this month. However, are there other recommendations anyone can come up with to lower my engine temperatures? My own short list to cool things down and erradicate the pinging is:

1. Change from 30 wt oil to synthetic.
2. Add a can of octane with each new tank of 91-octane gas.
3. If accessible to me, add a couple gallons of race gas, which can be found around L.A. if one doesn't mind a drive.

My timing is set at OEM, but I will double-check that. BTW: this is an '83 3.0 with 9.3:1 compression - all stock except for '74 exhaust.

I'd like to rectify this problem before I fatally damage my pistons and any other related part. So, if anyone has additional suggestions, please pass them on.

Thanks.

[air-cool-me]

Add a can of octane with each new tank of 91-octane gas.

are you talking about the little bottles of "octane booster"?
those are misleading as to how much they really do.

you might have a bunch of carbon deposits on top of the pistons making it more likely to ping..... a little water can cure that...

but im pretty sure an SC motor with stock timing ,at 230*, with 91gas should NOT ping... I'm sure the rest of the guys will figure it out..


best of luck but it might be "sunco super 100" time till you figure it out..

[jmohn]

While your noticing it probably is heat related your '83 should not ping on 91 octane (I've been driving (stop and go) in 90+ heat the past few days with 87 octane with no indication of any pinging). Do re-check the timing, you can even back it off a little to stop the pinging, the only thing that will suffer is a little performance. Check that the heat range on your spark plugs is correct also, if they're too hot the hot plug tip can cause pre-ignition. Someone already mentioned carbon deposits. Changing to different weight oil would have no effect on whether the engine pings or not. However, 30 weight, in my opinion, is way too light for your climate. Check the manual, I think 15-40 is the lightest recommended in your temperature, personally I use 20-50 (synthetic does give you a larger margin, but I still wouldn't go as light as 30).

Jerry M
'78 SC

[DavidI]

This might sound crazy, but don't gasoline companies change the formula during the summer months? If so, maybe that could be it....

I dunno. I just worked a double shift and am delirious....David

[JeremyD]

Yeah, octane booster is a bunch of bunk! I would go and buy a 10 gallon portable gas can - during the summer months when they change the formula I would add a couple of gallons to my tank. Should be fine from then on...

[Gunter]

30-weight in CA? Man, that's too light. Use 20W50 Dino, not synthetic, many people report more leaks with synthetic.
As for octane, 89 to 91 is good enough; some people even use 87, and yes, fuel formula changes a little with the seasons. Regarding pinging, check your timing; maybe it's too advanced?

[oneblueyedog]

Make sure all of the vacuum lines are tight. Make sure the intake runner boots are not leaking. Vacuum lines include the big ones connected to the deccel valve and warm up systems. 2 or three tiny leaks add up to a lot of extra air to go lean and ping.

My pinging went away after a tightening of hoses (gently snug) +91 octane fill.

O-rings in the injector tubes can also cause trouble. Outer and inner. Lots of threads on this.

[juanbenae]

Originally posted by DavidI
gasoline companies change the formula during the summer months? If so, maybe that could be it.

thats a likely cause. calif does change it gas formula during the summer months. fuel economy goes down in my commuter car about the time they are required to switch over to the "summer formula"

maybe a plug change?

[JeremyD]

My Taurus used to ping in california during the summer. I took it in cause I thought something was wrong - service told me they all do it due to the CA summertime gas - apparently the alcohol or ethanol % goes way up...

[MotoSook]

David...you should try the water or Seafoam carbon cleaning. I'm very syrprised that a 3.0 would ping at factory settings...are you rich enough?

[Paulporsche]

Along w/ mixture, check your warm control pressure.

[anthony]

Maybe he needs a new O2 sensor? The experts can correct me if I'm wrong but shouldn't it retard the timing if it detects pinging?

FWIW, my 81SC has never pinged and I've been running regular 87 octane as prescribed by the manual.

[dd74]

Originally posted by Souk
David...you should try the water or Seafoam carbon cleaning. I'm very syrprised that a 3.0 would ping at factory settings...are you rich enough?

Souk - yes, I'm running rich enough - I think. I'll look into this and the Seafoam as well. Thanks.

Anthony - I don't have an O2 sensor - there's no Lamba brain with my car.

Oneblueyedog - I will check the vaccuum-oriented parts of the CIS.

Gunter - I'll run some heavier oil when it gets changed as I put on the Carrera cooler. Before that, I think I'll run a couple cans of techron as well.

Thanks all.

[RoninLB]

I wouldn't drive it in pinging conditions.

[dd74]

I'll tell you guys this: after having this problem last summer and now again this summer, if the pining persists much longer, I might seriously consider ditching the CIS entirely and going with Tbitz's EFI. I can stand the thought that I might be wrecking my engine's internals.

As an aside, isn't all the CIS except for the intakes eliminated with Tbitz's EFI?

[dd74]

Originally posted by RoninLB
I wouldn't drive it in pinging conditions.

As in hot weather? That's when owning the car, in my opinion, becomes unfeasible.

[anthony]

Originally posted by dd74

Anthony - I don't have an O2 sensor - there's no Lamba brain with my car.

I guess I was thinking that all the later SCs had an O2 sensor. Maybe it's just a California thing? I would look at the tuning, maybe backoff the timing a bit, and check for air leaks as was previously suggested. Maybe also check the oil cooler and make sure it's not jammed up with debris.

[RoninLB]

Originally posted by dd74

As in hot weather? That's when owning the car, in my opinion, becomes unfeasible.

you gotta fix the prob somehow.

If I got caught in a situation where combustion was so off kilter that I'd be risking eng destriction I'd limp home under as much under throttle as possible. This will keep exhaust gas as cool as possible. Hard throttle will also lengthen the time the exhaust stays abnormally high.

You're dealing with air, fuel, and ignition being managed inside an envelope called a combustion chamber. The combustion event must happen when the piston is the best position to absorb the energy. Doing otherwise is like asking a pissed off bull dyke to dance.

[Carrera3.5L]

Originally posted by dd74
I can stand the thought that I might be wrecking my engine's internals.

Maybe this is the ticket that gets you your 3.2L or 3.6L DME motor that your wife wouldn't let you get a few weeks back?

Ralph

[dd74]

Originally posted by RoninLB
Doing otherwise is like asking a pissed off bull dyke to dance.

I always knew the 3.0 had a little b!tch in it.