Valve Clatter / Pre Ignition?

[alwcurlz]

I am having a problem with valve clatter and I think I may be close to a solution. What happens is when I am travelling down the road and the truck needs more power to overcome a hill or increase in wind resistance there is that valve clatter like the fuel is poor octane or the advance/retard is off and there is pre ignition. Thing is, this is all electronic and there are no codes coming up. What I discovered was that this spring as it warmed up to above 40° the valve clatter came back. I thought it went away on it's own since it never did it all winter. Seems to be temperature related. I swapped out the MAF with my brother's truck and it still clatters. Anyone have experience and resolve for this issue?

[Jsdirt]

You need better fuel.

 

My '07 NBS has done this on several occasions, using the 87 octane crap with 10% ethanol & 10% water that they feed to the sheeple out here in MA, all to keep the purple unicorns singing gleefully.... (treehugger speak - sorry if you don't understand. It's the state language...)

 

My '72 El Camino knocks just as bad on the same crap .... So much for electronics.

 

.... but it's all about unicorns breathing clean air, you know. Save the whales! FREE TIBET!

[alwcurlz]

Thing is, it only happens with MY truck, and not my brother's truck. And it only happens when the outside temp is over 40° and higher.

[VonDutch]

Thing is, it only happens with MY truck, and not my brother's truck. And it only happens when the outside temp is over 40° and higher.

 

Make sure the motor is not running hot

you may need to flush it

 

 

The temp gages on some of these trucks are less than accurate

mine reads 210* all the time regardless of the weather

 

Also you may need to run a different spark plug

check your plugs wires etc: and replace as needed

[Jsdirt]

Yeah, excess carbon buildup will do it too - especially if it's got some miles on it.

[Nytemare]

Thing is, it only happens with MY truck, and not my brother's truck. And it only happens when the outside temp is over 40° and higher.

 

Make sure the motor is not running hot

you may need to flush it

 

 

The temp gages on some of these trucks are less than accurate

mine reads 210* all the time regardless of the weather

 

Also you may need to run a different spark plug

check your plugs wires etc: and replace as needed

 

Your temp gauge is supposed to read the same temp all the time no matter what the weather is....that's how the cooling system works. Its supposed to keep the engine at the operating temp, set by your thermostat. 170*/185*/198*etc. if it fluctuates it means your cooling system is not doing its job properly and its time to flush, change the thermostat or some much bigger issues. You will get some movement in hot weather when your pushing the engine, ie towing, hauling heavy loads or into the gas.

 

for clatter your hearing, Toss a quart of ATF in your engine at 300-500 miles before your next oil change...the heavy detergents will clean out any deposits in your engine, and go right now and get a can of lucas upper cylinder lube with injector cleaner.

This one:

 

 

Do the injector cleaner first as it could be bad gas, this will take care of it in this tank. Than switch to another station if possible.

[alwcurlz]

I had the coolant flushed last year when I was back in Texas, where it was over 100° and it never overheated and doesn't run hot at all. I installed a new water pump this spring. New spark plugs, gapped correctly. New Knock sensors. New Oxygen Sensors. New MAF sensor. New EGR. New fuel pressure regulator. New Fuel pump. New fuel filter. I've tried all 3 grades of fuel from Chevron, Shell, Sinclair, Texaco, 7-Eleven, Racetrac, Cenex, On the Run, Murphy USA, Conoco, Valero, BP, Holiday, Tesoro, plus a handful of mom/pop stations. I've put transmission fluid in before oil changes, and I run full synthetic. I've put upper cylinder lubricant and valve/injector cleaners in, at normal and double strength. Still clatters/pre-ignition. I'll try changing the MAP and TPS sensors next. If that doesn't do it, then I'll try my scanner software, HPTuners. I'll take it to the dealership if that doesn't fix it. In the end I'll end up with burned valves I suppose if nothing fixes the problem.

Thing is, it only happens with MY truck, and not my brother's truck. And it only happens when the outside temp is over 40° and higher.

 

Make sure the motor is not running hot

you may need to flush it

 

 

The temp gages on some of these trucks are less than accurate

mine reads 210* all the time regardless of the weather

 

Also you may need to run a different spark plug

check your plugs wires etc: and replace as needed

 

Your temp gauge is supposed to read the same temp all the time no matter what the weather is....that's how the cooling system works. Its supposed to keep the engine at the operating temp, set by your thermostat. 170*/185*/198*etc. if it fluctuates it means your cooling system is not doing its job properly and its time to flush, change the thermostat or some much bigger issues. You will get some movement in hot weather when your pushing the engine, ie towing, hauling heavy loads or into the gas.

 

for clatter your hearing, Toss a quart of ATF in your engine at 300-500 miles before your next oil change...the heavy detergents will clean out any deposits in your engine, and go right now and get a can of lucas upper cylinder lube with injector cleaner.

This one:

 

 

Do the injector cleaner first as it could be bad gas, this will take care of it in this tank. Than switch to another station if possible.