1999 Ranger 2.5 4cyl pings???

Get the error codes read. A failed knock sensor will cause this and will not turn on the CEL.

Hi Jim V! Thanks for the response. I was told by dealer and Autozone that if the "check engine light" doesn't come on, it won't record any codes?? I also forgot to mention that the truck has a new "mass air flow" sensor about 6 months ago. I already tried cleaning the maf filament wires with contact cleaner.

They are wrong. Some codes are just recorded including the knock sensor.

Many times the code gets logged in, but because it doesn't meet x-criteria, no CEL (Check Engine Light) Some codes require 2 or 3 times of certain conditions to set the light, until then they can be listed under "pending codes" in many scan tools

Thanks Stephen! Typically will dealerships scan the codes for free or do they charge? Will they even do it without the CEL on? Autozone won't scan codes unless CEL is on!

Dealers don't to anything for free. Tell autozone it's been coming on intermittantly. They'll read it.

I read something about cleaning the wire in the mass airflow sensor that was supposed to stop the pinging. However, if you drive it long enough while pinging, engine damage will occur. It happened to me with my Ranger with a

3.0 V-6. I put larger tires on the truck and it started pinging. I presume it was the extra load on the engine due to the taller tires effecting the overall gear ratio. I noticed the coolant had turned brown. I drained it, flushed the radiator, then about 4 months later it was brown again. Combustion gases were getting in the coolant. The pinging (preignition) probably cracked the head or took the head gasket out. Ron

Thanks for the replies! I have cleaned the MAF sensor, in fact the sensor itself is only a few months old. I took the truck to a local auto parts store to scan the trouble codes. There were none! Am I to assume that all the sensors are working properly? Is it possible that it just simply needs a tune up. It isn't scheduled to have one till

100k and it only has 55k.

Pinging is pre ignition. Something is starting the combustion burn before is suppose to. Sometimes it is caused by carbon build-up in the combustion chamber, a run-rite fuel tune is suppose to burn out the carbon.

We sell it at our store, and I do believe it helps. I would start with a good tune up, and go from there..

Thanks for all the replies!! I have since switched to premium gas and will add a fuel cleaner additive for a couple tankfulls. The pingng does now seem to have stopped and the truck seems to run pretty well when up to normal operating temp. BUT the engine hesitates when cold!! The check engine light has never come on, so the emission system/sensors are probably ok. Does this sound like carbon build-up in the combustion chamber? I have read about a "water trick" where you take a warm engine and rev it while you take a vacuum line and feed water into the intake which supposedly helps break down the carbon build-up??? Is this safe??? I have called my local dealer and he wants $107 to clean the fuel injectors and from what he says, it sound very familiar to the water method... Fuel filter was changed maybe 7500 miles ago. Still has original plugs and wires but isn't scheduled to get new plugs and wires until 100k. It only has 55k... Any ideas??

Thanks! -mike

Take it to a shop and have them do the "fuel tune" That's what it's called at Firestone. The question is of liability. If you try this water trick and it tears up your engine, who pays? The "Fuel tune" by "run rite" has had extensive research done by Texaco.. Anyway, it they screw up you car you have a good chance of some reimbursement.

"Steve" snipped-for-privacy@hotmail.com wrote in news:uNice.665960$ snipped-for-privacy@bgtnsc05-news.ops.worldnet.att.net:

at 55,000 you should not need a injector clean at all. the water trick is for cleaning the cly it self. do not do the water if you do not know exactly what you are doing as major damage is possable. also at that milage there will be no build up in the cyl. you don`t need either one. KB

Thanks everybody!

OK, the saga continues... I have run 2 cans of B12, no help. I have replaced both O2 sensors, seems to run smoother, a little more power but pinging persists. It won't ping on premium gas as much, but I read where that is not good for an engine designed to run on 87 octane. I have run 89 (mid grade) for over 20k miles with no pinging, then all of the sudden, it pings. Others have mentioned the egr valve....I removed the hose from the top of the egr valve with engine running and engine continued to run with no change in rpm. Wasn't it supposed to stall? Help? Help?

Potentialy stupid question here, but have you checked the ignition timing? *CAN* you check it at all?? (Not sure if your igntion has a dist or not...)

No distributor... All electronic ignition.

OK, last 2 days it hasn't pinged, I can't explain why, but I haven't driven much though... Could it be that it took a couple days of driving for the computer to re-learn, since I disconnected the battery for 20 minutes? Here is what I find interesting though.... When I started the cold engine, after resetting the computer for the O2 sensor replacement, it ran perfect cold without any hesitation. The next morning I started it cold again, and it hesitated until up to normal operating temp. (which is what it did prior to O2 sensor replacement) I know that the O2 sensors aren't a part of the equation because it is still in open loop until normal operating temp anyway and the computer was probably running some basic pre-programmed calculations until it had a chance to re-learn......BUT does the fact that it ran perfect after a reset mean that there probably isn't a carbon build up problem but rather some sensor misreporting info to the computer? Also, how long does it typically take for the computer to re-learn after a rest?

OK, last 2 days it hasn't pinged, I can't explain why, but I haven't driven much though... Could it be that it took a couple days of driving for the computer to re-learn, since I disconnected the battery for 20 minutes? Here is what I find interesting though.... When I started the cold engine, after resetting the computer for the O2 sensor replacement, it ran perfect cold without any hesitation. The next morning I started it cold again, and it hesitated until up to normal operating temp. (which is what it did prior to O2 sensor replacement) I know that the O2 sensors aren't a part of the equation because it is still in open loop until normal operating temp anyway and the computer was probably running some basic pre-programmed calculations until it had a chance to re-learn......BUT does the fact that it ran perfect after a reset mean that there probably isn't a carbon build up problem but rather some sensor misreporting info to the computer? Also, how long does it typically take for the computer to re-learn after a rest?