If the engine is pinging/detonating and the EGR valve is not doing its job it will cause a high combustion temperature and NOx will sky high and cause it to ping. Don't always rely on the computer to give you something when there's a problem within the engine management system it'll be nice though if it does

Answered by rasmataz
68 questions asked

thanks. I hope this turns out to be the problem. It's highly inconvenient buming a ride to work when you have a 45 mile commute.....

Response from hopk6344
1 question asked

Well, replacing the EGR solenoid and cleaning the injectors/combustion chamber seemed to fix the problem. I picked the van up yesterday, and stress-tested it by accelerating up a steep hill from a dead stop. No pinging or preignition noises. It still seems odd that the solenoid would not have tripped a error code on the computer. I'll monitor it closely over the next month to make sure it's not a temporary improvement. Thanks everyone for your suggestions. I'll be using this service again!

Response from hopk6344
1 question asked

Thank you for letting us know that your problem was resolved successfully with help from our expert contributors.

Answered by rivermikerat (expert)
5,495 answers provided