1997 pinging on 93 octane

[Andrewsreef]

THank you for the response and you just may be correct. My CEL came back on today and I bet it is the lovely P0401 (will check it when I get to my scanner).

I still have not replaced the VSV but will do so on Sunday time permitting (I am a little concerned this is over my head so may bring it to my mechanic on Monday). I have already replaced the EGR and the Modulator.

Thanks

Andrew

 

[mabrodis]

Your temp gauge reads in the lower 1/3 all the time? That doesn't seem quite right to me. Obviously the gauge has no numbers so it doesn't mean alot anyway, but mine ('97 LX450) has never been that low. Mine reads either dead level, or a frog-hair below that, but well above a 1/3 line in the gauge. Maybe your gauge is getting a lower voltage (bad wire somewhere)...hmmm...infact (light going on), if the temp sending unit is bad, telling the computer the engine is colder than it is, could that not create this exact problem? (engine warms up computer adjusts mixtures between a cold engine and hot engine? Guessing here..) Best way to tell is with a OBD2 device to measure coolant temp, see if it's in the 200-215 range which is around what they should run I think, if the computer claims it's lower than that, that would be very suspect IMO.

As for the OBD-II diag stuff, do you have a laptop? My stepdad bought a connector off http://www.obd-2.com, it was in the $140 range I think, not dirt cheap but far cheaper than most other systems out there. Obviously easiest to use if you have a laptop, but you could (don't laugh I've thought of this) setup a desktop computer inside the vehicle, extention cord to power (sitting in the garage/driveway), or use a invertor to power it all, odd, yes, but heck if it find the problem...can't knock it (heheh).

Certainly not normal, I have never heard mine ping/knock, I run 85 octane gas at up to 13K feet on trails and have never heard anything out of the ordinary.

Good Luck..
Mark Brodis

 

[Andrewsreef]

My bad, I would agree with you it is a little higer than 1/3 but a little less than half way.

Thanks

Andrew

 

[lurker]

Sounds a little like your plug wires could be in the wrong order.

 

[cruiserman]

Mark, Your gauge is reading high .

 

[mabrodis]

Mark, Your gauge is reading high .

Probably ...oh well, has never changed in the 75K miles I've put on it...I have another thermostat to put in, just haven't done that yet.

My high gauge is just compensating for the gas gauge which always reads empty...argh..

-Mark Brodis

 

[Andrewsreef]

Ok, I replace the VSV this am and the CEL is now out. THe Pinging is about 90% better but not totally gone. I will drive it a while and see if the CEL stays out. After doing this work I now have 2 more concerns.

I replaced the PCV valve and noticed some sludge around the valve and in the area around where it goes into the valve cover. Is this normal to have some sludge around this area or is my truck engine full of this crap??? My oil stays very clean between changes every 3k. I use castrol 10W-30. I have only had the truck for about 8 months though and have no idea what service the prior owner did.

Also, I checked my head gasket using the method described in this forum of looking into the overfill resivore and looking for bubles. I reved the engine to about 2-3k and looked in and saw some bubbles at first (may have been due to the work I did on the VSV??). I watched it for about 5 minutes after this and saw no more bubbles. Does it sound like I am ok???

Thanks again. I am kind of freeked out about this sludge thing as I love this truck and have a small fortune in it now (purchase and all the repairs).

Thanks

Andrew

 

[Beowulf]

Andrew,

The P0401 is a 2 trip logic. According to Toytoa (and other sources) a malfunctioning EGR system can cause detonation (pinging.) I have not seen it myself but that's what the technical articles say.


>> Is this normal to have some sludge around this area or is my truck engine full of this crap??? <<

Probably somewhere in between these 2 extremes. It's not "normal" and your truck probably isn't full of sludge. Do some frequent LOF changes and monitor. Send off a sample for analysis if you're really concerned.

>> may have been due to the work I did on the VSV <<

Unrelated systems.

>> Does it sound like I am ok??? <<

Yes.

-B-

 

[dnp]

OK, I'm sure I'm gonna kick myself for asking this, but what does VSV stand for? What about LOF?

 

[ian]

Vacuum Switching Valve
Lube Oil Filter (ala Jiffy Lube)

 

[dnp]

Thanks, Ian........nope, though I've had extensive automotive experience, would've missed both of those!............*^&%, I hate it when I have to admit ignorance!

By the way, just today I noticed mine is pinging just off idle....no pinging when accelerating at any point after that, just when accelrating from idle.........I have been running 87 octane without noticing any problems, but this just showed up today........

dnp

 

[Andrewsreef]

Ok, I have been driving this truck for a while now since changing the VSV and things are shaping up. My oil consumption is not an issue with the Delo 15W-40 as I used no noticable amount in 1000k. I think I am going to try Mobil 1 SUV next and see if it works good. I have done the head gasket test with the overflow several times and I have no bubles so I think I am ok on that for now.

The only thing puzzeling me now is the very, very mild pinging I still think I am hearing some time. This is only in the 2500-3000 RPM range and not all the time but more when the truck is fully warmed up after being stuck in traffic. It may not really be what I am hearing but it does sound like it. If it was knocking wouldn't the knock detector retard the timing and stop it? I am going to try some lower octane fuel and see if it changes at all. I still need to get a temp reading on the radiator fluid and see how hot it is running. The radiator is new so that is good.

The truck is running great and the problems seem to be stabilizing. I am going tonight to pick up some Redline Gear oil to do them again after 10k since my change. I am going to also drop the pan again and change the filter and start slowling converting it to the Redline ATF. Also plan to do the Birfield service soon with my Cousin's help (I hope).

I watch my overlow weekly to make sure I am not consuming any fluid. Hopefully I am going to start being able to enjoy this thing.

Thanks for all the help.

Andrew

 

[Scamper]

Andrew - you may have answered your own question a while back. I read some articles on another website about using high octane fuel in a vehicle that does not specify it. According to them, using too high an octane may result in carbon buildup which in turn might be causing your mild pinging. I'm not sure about this info, but regardless, it would be inexpensive to use a decarbonizing treatment and see if things improve. I periodically run a can of the 3M stuff (08957 intake system cleaner) through just as a PM item and have never had a pinging problem even with the S/C.