Another Pinging problem!! 20 dollar Paypal reward if you can fix it!!! No Joke!!

[mustangman94]

Ok I have been on here before asking about pinging. I have a 94 Mustang GT Conv. I have replaced the IAT, cleaned/checked MAF, checked O2's, replace spark plugs, etc etc.. (The car is bone stock for proformance also) We stepped the timing down to about 0 (spout out). It is really slow and bogs down and it still pings on mid grade 89 oct. gas!!! But I noticed that the exhaust smells almost like diesel gas, coming from the tail pipes. Also around the outside of the pipe it gets really black, like a carbon build up. I wash the car about once a week and it comes back every time. In the picture the car was washed yesterday. It works its way towards the front of the car along the tail pipe about a 1/2 inch. Also the inside of the tail pipe is really really carboned up. I cleaned a little spot as you can see with my finger to show the build up. I'm guessing all this is caused by being super lean. It pings when you are about 3000 and up and more than 1/2 throttle. Which makes me beleive the fuel pump is not getting the pressure there. We also replaced the fuel filter. Should I check the pressure at a dealership or is it something else.

Thanks for any help you guys can give.

 

[slidewayz94]

run some sea foam if you haven't already.

 

[mustangman94]

O yeah I have done sea foam about 3 times and twice was through the brake booster.

 

[194stang]

If it really sooty looking, I would say its rich. Whats the plugs look like? How hot is the motor running? I would run the codes on it and go from there. There has to be something in the ignition or puter.

 

[mustangman94]

If it really sooty looking, I would say its rich. Whats the plugs look like? How hot is the motor running? I would run the codes on it and go from there. There has to be something in the ignition or puter.

The motor runs a little hot. I used a code reader and nothing came out at all.

 

[194stang]

I dont know man. my pipes look darker than that. Do you still have the cats on it? It will smell weird without the cats.Try checking the timing advace. By that I mean check it with the spout in, and just rev the motor up some say 2500 or so and see what the timing looks like.I dont know what the stock curve looks like, but with my chip it goes to like 34 degrees total. Other than that only thing I can think of is its running to hot, that will make one ping. You running the stock gage? Good luck , I feel your pain!

 

[mustangman94]

I dont know man. my pipes look darker than that. Do you still have the cats on it? It will smell weird without the cats.Try checking the timing advace. By that I mean check it with the spout in, and just rev the motor up some say 2500 or so and see what the timing looks like.I dont know what the stock curve looks like, but with my chip it goes to like 34 degrees total. Other than that only thing I can think of is its running to hot, that will make one ping. You running the stock gage? Good luck , I feel your pain!

With the spout in and reving it, the timing is right around 30. The cats are still on. I also have a 180 thermostat, so it isn't the engine running hot.

 

[194stang]

Yea I got a 180 stat too. but it still runs about 210 with the air on right now. Of course its been in the mid 90's here with pretty high humidity. Sorry man, I am out of ideas, wish I could help you.

 

[CManT1914]

Check your plugs, if they're black and sooty, there's too much fuel in there. Check your fuel pressure, it should be 30psi or so at idle, and 38-40 under load. You said you already pulled the codes and came up clean, so it probably isn't a sensor, unless one is on it's way out but still within specs. Have you checked the ECT (engine coolant temperature) sensor? Might check that one out. Good luck, let us know what else you find.

EDIT: Oh yea, and FWIW, a t-stat doesn't do a whole lot for lowering temperature, you need a manual fan switch to turn on the fan earlier to accomplish that.

 

[mustangman94]

Check your plugs, if they're black and sooty, there's too much fuel in there. Check your fuel pressure, it should be 30psi or so at idle, and 38-40 under load. You said you already pulled the codes and came up clean, so it probably isn't a sensor, unless one is on it's way out but still within specs. Have you checked the ECT (engine coolant temperature) sensor? Might check that one out. Good luck, let us know what else you find.

EDIT: Oh yea, and FWIW, a t-stat doesn't do a whole lot for lowering temperature, you need a manual fan switch to turn on the fan earlier to accomplish that.

I replaced the ECT sensor about 4 months ago. I don't think it is because the engine runs hot, becuase it will ping in 50 degree weather just as bad as it pings in 90 degree weather.

 

[mustangman94]

I've heard that a fuel mixture could be so lean that it acts rich and so rich it acts lean. But could a engine ping if it was way to rich. Because the only thing that I think could be wrong is low fuel pressure which causes an extreme lean A/F mixture.

 

[CManT1914]

I've heard that a fuel mixture could be so lean that it acts rich and so rich it acts lean. But could a engine ping if it was way to rich. Because the only thing that I think could be wrong is low fuel pressure which causes an extreme lean A/F mixture.

Just check your fuel pressure, the gauges aren't expensive at all, and then you'll know for sure if your pressure is to low or high.

 

[HISSIN50]

I like Chris's advice (and others) about checking fuel pressure or volume at higher revs (demand). It sounds like your pump is on the outs. check pressure and go from there.

Good luck.

 

[95snoozer]

on stock heads mine would ping if i got on it 195+

i ran stock timing

do the free high speed fan switch mod and or a radiator and then

get heads

 

[mytight95]

unplug the IAT sensor on the intact ducting, and drive... see if it goes away..... Then do an ohm test on your ECT sensor...if you replaced your ford one iwth a cheap aftermarket on i bet that is what it is....


just some thoghts...

jason

 

[mootang]

0* is pretty low for the timing.

10* is stock.

 

[bimmertech]

first thing i would do is do a top engine soak. that seafoam **** is for the autozone crowd. go to any chevy dealer and ask for a can of top engine cleaner, remove your spark plugs and fill each cylinder up with said cleaner. wait 3 hours then go out and rotate engine over then refill and let sit overnight. in the morning go out and motor over the engine for a good little while(until the cleaner is all out) then blow out the cylinders with shop air. reinstall the plugs and start it up. it will take a while to get it started and will smoke a little, but once it does start let it idle for a minute then change your oil. then go run the piss out of it. nevermind, i just read your original post and didn't notice you checking for vacuum leaks. check vac leaks first then do top engine soak.

 

[HISSIN50]

Bimmertech, I take it you have had good luck with Top end cleaner? I considered it awhile back and chose not to after reading some info elsewhere about folks having had some issues afterwards. Have you ever seen issues after its use (seems to me you are a tech, so perhaps cars dont hang around long enough to find out?).

With the vac test mentioned, I would also hold the throttle and note if the reading drops (suggesting an exhaust restriction, like cats).

FWIW, a stockish motor should pull close to 20" hg at warm idle.

Good luck.

 

[bimmertech]

Bimmertech, I take it you have had good luck with Top end cleaner? I considered it awhile back and chose not to after reading some info elsewhere about folks having had some issues afterwards. Have you ever seen issues after its use (seems to me you are a tech, so perhaps cars dont hang around long enough to find out?).

when i worked at a chevy dealer a while back it was a tech serv bulletin. ford has the same bulletin and procedure for 4.0 sohc and prolly some others as well. i have done it to a ton of vehicles at work and all of my own and with no adverse affects. the problem is people would put the plugs back in and hdro lock the damn motor giving the procedure a bad rap. there is a couple other procedures, but require expensive tools that can not be aquired easily. for example there is the sprayer that shoots walnut shells into the engine, it's what bmw and mercedes use and really works as it cleans the valves too. you would be amazed at what a real carbon cleaning does for your engine.

 

[final5-0]

A couple of things I see in this thread are:

1) If you are too rich, the extra fuel should only help the ping thing.

2) Is it possible that your hb has spun (is that a word? ... lol) and your spark is too far advanced?

Later
Grady