Pinging getting worse

[sjjones]

Folks,

I've got a 94 Explr 4 L. I've got a pinging that I've not been able to get rid of for over a year. Some days, I don't hear it at all. Other days, I get it pretty bad. It doesn't ping at all until the engine gets hot. I primarily notice it at higher speed when I punch it.

I've cleaned the MAF, changed plugs, changed the air filter. Tried higher octane gas (no help), run Chevron Techron through it, etc. I have had to add a "little" coolant on occasion over the years and am now wondering if I maybe had a head gasket leak letting in some coolant. No smoke at any speed. Any suggestions on what to do next would be greatly appreciated.

BTW, is replacing the head gasket something a person can do themselves? I've got the tools, but not the experience. Many thanks.

 

[dmasini]

You've got a 94 so I'm assuming you have the 4.0 OHV right? In my old 97 I ran a higher octane through it to get rid of the pinging (I had the SOHC) and it made things worse. I ran Sea Foam (have you tried this yet?) through it and that worked for awhile but the ping came back and I wasn't able to do anything to stop it after that.

Now I have a 2001 X and it'll ping/rattle some but only when I get on it and it's near the 3000 mile mark to change oil. I tried using synthetic oil for awhile but that actually made it worse too. The more I read on the matter the more I realise it's just a product of Ford's engines.

As far as the head gasket leak wouldn't you be able to see that in an oil change? Never replaced one before...

 

[MrShorty]

Along with decarboning the cylinders, I don't see any mention of doing anything with the lower intake manifold. It's very common for that gasket to leak a little which causes the engine to ping (and use coolant and/or oil). Most of the time, just tightening the bolts is enough to fix the problem.

 

[Positive Vibes]

Changing the tranny modulator helped my pinging.

http://www.explorerforum.com/forums/showthread.php?p=1251474#post1251474

 

[thammel]

I have a 2002 xls with 4.0liter v6 and had bad pinging and here's what I did to solve it:
1) replaced front O2 sensors (had a code saying one was bad)
2) replaced egr valve
3) cleaned MAF sensor (removed and used q-tips with proper solvent)
4) IMPORTANT: disconnected battery for an hour

This last step was crucial to getting the cpu to relearn the proper setup. The pinging did NOT go away until I disconnected the battery.

FYI, I also degreased the engine with Gunk, but don't think this had anything to do with it.

Tom

 

[sjjones]

Pinging continued

Folks,

Thank you for the replies and idea. Yes, I have the 4 L OHC. I did a lot of achive searching and asked a few questions last year on the same subject. I should mention that I have collected a lot of post over the last year on the subject. In addition to what I mentioned doing in my original post, I have also tried tightening the lower bolts. Perhaps I'm doing something wrong but I could get them to budge any tighter. I changed out my egr valve, but not for pinging - just maintenance.

I went to the ford dealer and purchased several cans of what they sell instead of seafoam. I've not used the product yet for fear of locking up the engine. The idea just seems a little risky because there is always the risk of dislodging some carbon and doing damage to the system. I still my try it though.

What I was thinking was because I'm losing some coolant (slowly) and can not find the leak, that I may have a head gasket leak - which has been mentioned before. I also found one spark plug with a light colored crusty substance on it.

I'm just trying to do the simpliest things first and looking for ideas. Many thanks.

 

[MrShorty]

What I was thinking was because I'm losing some coolant (slowly) and can not find the leak, that I may have a head gasket leak - which has been mentioned before. I also found one spark plug with a light colored crusty substance on it.

Any chance it was the #5 plug (middle plug driver's side)? If so, that is a classic symptom of a lower intake manifold gasket issue.

 

[Maniak]

I haven't seen a seafoam equivielent at ford. What I have seen is Motorcraft injector cleaner that you do NOT run through the tank or vacuum lines..
Just a heads up, make sure you don't have the stuff that I used as it will mess up the fuel system if you put it in the tank.

The motorcraft stuff I've seen/used is run through the fuel system a different way (its an injector cleaner, and is very expensive.. I think $30+ per bottle).. Here is how we did it (shop did, I watched/learned)..

You put put the motorcraft cleaner in this can looking thing with a little fuel (I think it was a 50% mixture).. The can has 2 hoses on it.. one with a regulator to an air compressor.. The other goes to the fuel rail (pressure test port)... You need to trip the inertia (sp?) switch so the truck won't turn on the fuel pump.. Now bring the pressure up on the can to 45psi or so.. and start the truck.. It will run poorly, and all kinds of crap comes out of the exhaust. We did that for 2 bottles of this stuff..

It worked well, it really cleaned out my injectors...


~Mark

 

[Longjohn119]

If you just tightened your manifold bolts willy nilly (Without a good torque wrench and in proper order) you may have done more harm than good ... you are working with aluminum, not cast iron like in the old days and proper torquing is a NECESSITY or you warp the hell out of them real easily ... When I retorque something I back off the bolts half a turn **in reverse order of torquing sequence** and then torque them in proper order

Also if the torque was off or there is even slight warpage you may have blown out a part of the gasket (although that's rarer on an intake gasket) and no amount of retorquing will fix that ....

It sounds to me like you are getting air in the intake where it shouldn't be coming from (ie. - after the MAF sensors) and the two most common places on these motors seems to be the intake gaskets but I'd also pull the hose to the transmission's modulator valve and check it for tranny fluid, if it's being sucked into the intake after the sensors it will also screw up the air fuel mixture

I've never heard of anyone harming their engine from the decarboning it **properly** but I would change the oil after putting a few miles on it (makes sure you've burned out all the loose carbon) ... in fact after decarboning the motor is a good time to run some engine flush through it too before you change the oil ....

 

[sjjones]

More UPDATE

Mr. Shorty,

Yes, it was plug No. 5. I had read before that this is a sign of lower manifold gasket issue. My lower manifold gasket has been retorqued with no help. I suspect this issue has been with me for a very long time as I have lost "little bits" of coolant since I got the vehicle in 1996. I've actually retorqued the lower manifold bolts two different times - none were loose to start with. In prior posts, I've read that those folks who corrected a lower manifold problem that was causing a ping, found that several of the bolts were loose. None of mine were loose.

I've read that the 94 were notorious for having a problem with bad manifold gaskets and that Ford came out with a replacement that is much better. If I was confident that it was a manifold gasket issue, I would replace it in a minute. I'd do it myself if I had more confidence, but I'd pay a good shop to do this for me.

Longjohn119: Right you are about properly torquing the bolts in order. Learned that early on with my motorcycle repairs - seems everything on the motorcyle is aluminun

You mention intake gaskets, could you please let me know exactly which gaskets you are referring to?

Transmission modulator value - sounds like something I can do myself. I have a manual and of course should look up the location of valve myself; however, if you were so kind as to kind of work me through the process, I would be most appreciative. Nevertheless - you have given me a new idea that can be done without great expense and I thank you kind sir. I'm a firm believe in doing as much preliminary testing/checking as I can prior to digging into things and sometimes making the situations worse.

I'm pretty dumb when it comes to modern day engines - but I'm quite handy when it comes to working on Goldwings