88 olds pinging

[angel84elco]

whats up guys I have a question so my car is all stock runs very good passes smog and all but I noticed that if I drove for a long time non stop it will start pinging a little and go away after a while? Any ideas on how to fix this? Thanks in advance

 

[Texas82GP]

I had trouble with a pinging 307 back in the late 90's early 2000's. Here are some thoughts....

1. Is the catalytic converter original? If so, I would start by replacing it with a more modern, less restrictive direct fit unit from Walker.

2. Check the EGR diaphragm with a hand held vacuum pump to make sure it is still intact.

The converter on the car I was working on was partially plugged. The stock converters are fairly restrictive when new. The EGR diaphragm on the car I was working on was bad. When I replaced these two components I couldn't believe how well the car ran, and it ran fine before but pinged at part throttle cruise and was fairly gutless, even for a 307.

Hope this helps.

 

[pontiacgp]

Sounds like a carbon buildup on the pistons. With the engine at running temperature try pouring a little water slowly down the carburetor which will steam clean the combustion chamber.

 

[olds307 and 403]

All good advice above, remember the 307 swirl port runs a retarded amount of timing advance, anything off and it will ping. Are you running ethanol fuel?

 

[foxtrot]

Sounds like a carbon buildup on the pistons. With the engine at running temperature try pouring a little water slowly down the carburetor which will steam clean the combustion chamber.

If performing the above, mist the water from a spray bottle and do not pour the water.. Also, do this with the original cat converter and not with the new one.

 

[angel84elco]

Thanks guys I know the converter was replaced! I run 91 since that’s the highest grade out here in California. I’m thinking about going ahead and changing out the EGR valve. It’s weird that it only happens after a long drive never happens when I drive to work and back or go for a small cruise and she starts and runs really good. And I know the timing is good adjusted that to the original specs

 

[Texas82GP]

Isn't EGR normally active during highway cruise?

 

[angel84elco]

Isn't EGR normally active during highway cruise?

I think so? I had seen in the manual about a light pinging noise is normal sort of like a gas saving thing I have to go back to look at it, but I do notice if I get on it the pinging will go away as well. But I’m not one to really get on it I mainly cruise it

 

[Texas82GP]

I don't think pinging is normal, especially running 91 octane. That's a low compression mill.

 

[Canon_Mutant]

Nope, not normal, but there is what is called lean burn mode that it will go into when light throttle, OD, and lockup to maximize fuel economy. Believe it or not, your 91 octane can even cause this. These were the last tables we dicked around with getting my big block to run on the triple C. Of course, it needs premium but we got it to work. It seems counter intuitive but try 87 gas and, as someone else mentioned, if your egr or even your gas fume canister valve are sticking, can also cause it. Just a few ideas for you.