Detonation problem fixed

[drchemistry]

I was having problems with my 95 Taurus 3.0L engine detonating (140k mi). It would knock whenever I tried to accelerate, especially with the AC on and in hot weather. Since this can do damage to the engine I wanted to get it fixed and expected to have to part with $$ in the process. 'Started by checking one of the plugs, and found that the electrode was shaped like a ballpoint pen. Platinum plugs are supposed to go up to 100k mi, but these only had 60k. I replaced them anyway and also put a can of Sea Foam injector cleaner in the gas tank. This nearly eliminated the engine knocking! I finally sucked 1/2 can of Sea Foam into the PCV vacuum hose with my wife on the gas keeping the car running. 'Shut it off for 5 min and restarted, letting it run until the smoke cleared. During a subsequent test drive I could detect no engine knock at all.

Now that the engine is quieted down, a clunking sound from my front suspension is annoying me. Onward into battle...

[shorod]

Many platinum-tipped spark plugs do have a stepped appearance to the electrode, so what you saw could have been normal. Thanks for sharing your experience in remedying the detonation.

As for the front suspension clunck, I'd suggest you check the condition of the anti-sway bar end links. If they are tight, then you may find your subframe bushings are the source.

-Rod

[Millermagic]

I've changed spark plugs and did the seafoam and that didn't help the knocking. My next thing will be a 180 degree thermostat.

However, when I tried the seafoam my intake manifold went boom and my PCV valve flew out of the engine bay.

[shorod]

Originally Posted by Millermagic

However, when I tried the seafoam my intake manifold went boom and my PCV valve flew out of the engine bay.

How were you adding the SeaFoam!?! Sounds like you may want to consider replacing the PCV valve. It appears to be allowing crankcase pressure to build, unless you're saying it flew out of the intake end, then it sounds like it did its job.

-Rod

[Millermagic]

My car likes to backfire out the intake - especially when revving it in neutral. I've had some pretty good backfires even while trying to start it in a parking lot or a driveway.

I was adding the seafoam through the brake booster slowly. The car started to cough, then it stalled for a second and tried to catch itself. Well all the seafoam in the intake manifold decided to blow up when the engine tried to keep running.

[shorod]

Seems like that aggressive backfire could be the cause of the knocking. You don't happen to have the SPOUT shorting plug removed or something goofy like that that may be messing up the timing, do you? Did the knocking/backfiring happen to start after replacing the camshaft position sensor or something else?

-Rod

[Millermagic]

The car has always knocked, even when it was new. It doesn't seem to do it so much in the winter when it's cold out - that's why I think a cooler thermostat would help.

However, the 2 seafoam attempts along with colder spark plugs did help a little. Some of it can be attributed to carbon - the car has a lot of short trips. For a while (before the seafoam) it had a nice case of valve tap from carbon.

But if I'm climbing a hill on a hot day it will ping. For fun (or I'm hoping to blow up the motor before it's out of extended warranty) I'll press the pedal farther down. It will ping worse and worse. Then it will reach a point where it will just lose power and knock really bad. If I let up, I'll get some more power. Seems to do it around 2-3 on the vaccum gauge, where it used to do it at about 5-6.

I really like the car, and would recommend one to anyone ... this is my only complaint about it.

[shorod]

Have you tried different fuel grades to see if that helps? Also, are the spark plugs an OEM style and heat range rather than a multiple electrode type?

-Rod

[TaurusKing]

I don't know, 180 thermo, shouldn't really need to do that.. Pinging from day one??? Maybe your intake valves dirty up relatively quickly after a cleaning, especially with the short driving trips, a cold thermo may exacerbate that problem.. I would just do more frequent cleanings, Seafoam, whatever, I think Ford makes a good cleaner.. in my case, 94 Taurus 3.0, i have to...

[Millermagic]

Right now I'm using Autolite A104 plugs, which are copper tipped cooler plugs. When the car was new, a short trip would be like 1 mile. Now a short trip for me is 20 miles and an average trip is about 45 miles ... granted I only drive like once a week now that I'm at college.

Still during the summer I didn't drive that much.

But if I give it time to cool down, it won't ping until the engine comes up to temperature. The general concensus on rangerpowersports was that the combustion chamber got too hot on the vulcans. But mine won't ping in the higher RPM, only when it's pulling hard at lower RPM

[drchemistry]

Here's an update on my 95 Taurus detonation issue: In the month since my original success with a Seafoam treatment, I've had several instances of recurring engine knocking. Thus the problem doesn't appear to be as "fixed" as I had thought.

[TaurusKing]

Magic, what are your compression numbers??? You have the 3.0 vulcan????