Contour Enthusiasts Group Archives Forums General Troubleshooting Part throttle engine ping

99 SE 2.5 57,000 miles, driven hard but personally well cared for. No other problems at all.

Ever since I purchased the car new, there has been a part throttle ping while under load. always in the summer months. Obviously, I cannot adjust the timing. I have had the computer "purged" 2 times by the dealer. Clean air filer, new plugs (old ones were clean) Could it be some sort of timing issue? maybe running too hot? (how would you tell?) I am about to go to water wetter and no coolant to see if that helps. suggestions?

The injector rebuild that is part of the intake manifold overhaul has cleared up pinging for others. A couple of doses of injector cleaner may help also. I noticed pinging when I installed an extra resistor in my IAT circuit, so the intake air temp measurement does seem to affect timing & pinging. I think clean EGR passages will help reduce pinging, but I'm not sure why??? Is your temp guage on the lower half of N O R M A L ?

The temp guage has never deviated much from 1/4 off the peg even on the hottest, air-conditioned days.

I should clean the injectors anyway with the mileage I got. You mentioned EGR... is that controlled from the computer or mechanical? This is after all just a part throttle problem that goes away when you mash it. I believe EGR is supposed to only be "on" during part throttle. You might be on to something there, I will check. Would reducing the coolant temp via a thermostat change or new coolant mix be a good idea? I have my doubts it would have much effect on this car.

Check the operation of EGR,on of its functions is helping to reduce ping...

Nice description of the problem.

FWIW, I and others here have had this problem and with the recent weather, it's back......

Some FI cleaner makes it go away (I think) for a week or two and then its back. 92 octane lessens it but not all the way.

If someone has actually cured this problem (short of Lance's intake teardown) please post!

Thanks,

Dave
'98.5 SE V6 MTX