92 caprice classic how to stop pinging going up hills? has new egr valve raised rear wheels put in drive works new knock sensor tap on engine dosent seem to ****** like it should ? set timing to spec has 100,000 miles nice car dose this on light throttle heard about an updated prom

P0121 is a TPS circuit code. It won't cause a noise at all

pinking, aka, pinging, knock,and best of all detonation (truth it is)
pinging does not happen, deceleratiing ever, that is pure noise

pinging happens under load, (hills) and lean air fuel mixtures.
and a dead EGR valve.

so engine noise, buy a $5 stethoscope,
listen for exact source location
or get it serviced.

old post.,

Sound like you jumped a tooth on the timing belt. Change it immediately. If it jumps more or completely fails you will bend all the valves. Just make sure you time it correctly. However a bad Mass Airflow sensor would cause the RPMs to go crazy. But the pinging is most likely the valve tapping the piston and needs immediate attention as well.

The knock sensor is famous for causing all sorts of trouble If you have a code for it, it probably needs to be replaced.

It could be a faulty sensor, valve or blockage in the EGR (tube) from a carbon buildup.

in some cases it may be a problem with the ecu

Hello, Thomas. Check the knock sensor. This sensor is suppose to send signal to the computer if the engine start to knocking or pinging. The computer will change the setting on various other components to keep from doing this knocking or pinging. I remember in the older cars that weren't fuel injected but carbureted and had to burn high octane fuel. If one put low octane in the fuel tank the engine would knock/ping, and continue to run after the ignition was turned off. Try the knock sensor or do an diagnosis test on it. Look in your owner manual it tell how to self diagnosis test on you car. GB....stewbison

Try better gas for a tank and make sure it's the transmission is downshifting when you go up the hill. After that the valves may need adjusted or replaced.

P406 is a EGR code, EGR will also cause a knocking/ pinging sound when there bad. Very common problem. The position sensor inside the valve goes bad. Your going to have to replace the whole EGR valve and it can put out variety of codes from P0401 to P0406. The new valve will solve the problem and easy to replace, you can pick one up at Auto Zone and they can give you the step by step instructions to replacing the EGR with common tools. Good luck and hope this helps.

Check your tail pipe for color. If insides are black you are running rich and it all may boil down to an oxygen sensor or an EGR valve. EGR valves are the most common causes for the 'check engine' light to come on. Your trouble codes will tell you what it is. Some auto stores will check it for free or you can buy an inexpensive checker.

Remove the black octane shorting (one time timing ****** adjustment) bar located near the ignition module ( the connector the bar goes into looks like a fuel injector connector), this should stop the ping, make sure the right jumper is removed, if you pull the wrong one the truck will lack power, if you get the right one the ping will stop and you will feel no change, U may loose a little MPG. If you can't locate it the dealer will do it for little or no charge, just tell them you want the octane adjust short5ing bar removed, did many of them on trucks like yours, the 2300 has a pinging issue, they all do, Mazda and the Ford Ranger.

How many miles on your caprice.