94 stang headaches

[ribsey80]

Hi guys. I am new to this site but have been a mustang freak forever. I have a 92 5.0 convertible that ive supercharged and the whole bit. I just recently purchased a 94 hardtop 5.0, 5spd that is stock except rearend gears, full exhaust with headers and flows and a Superchip. I am having a couple problems that I cant figure out. First, my tach has a mind of its own. It works one minute and then not the next. It even goes backwards sometimes. Second, it seems to be eating fuel. ( Not just because of my heavy foot ) I can only get about 300 klms to a tank and she pushes a little bit of black every now and then like its overfueling. Third, she will "ping" ( very rarely ) if I step into it even with 94 octane. All these may be related. Could the computer be trying to compensate for the tach not working? Any help or advice would be greatly appreciated. Thank you

[XR1stang]

I can't speak immediately to the problems with the tach or the rich condition that you are speaking of, but the pinging is something almost all 94/95 owners are familiar with.

Our model cars are notorious for pinging (mine got the name pingmobile a while back) and about the only thing I have found that can "fix" that is to drop your timing down low. When I had stock heads I had mine down to around 10 because of the pinging. I tried high octane (which sort of helps), octane adders, new radiator, fan, etc and none of them worked. Lowering the timing helps a lot.

Once I went to aluminum heads though all the pinging went away. Good luck, and I'll think on the other issues you have listed.

[Hethj7]

Have you pulled any codes yet? I would say that would be a good place to start. Mabye it rich condition is being caused be a bad o2 sensor ?

[ribsey80]

Thanks for the input guys!! I did pull some codes. It came up with 212 - no tach input to processor spout. I check all the connections I could think of but it didnt help. The other codes were 314 & 311 which said thermo air system not working Bank # 1 & 2 . We found that the air box was disconnected and that seemed to solve that.

[Hethj7]

Well, I wish I knew how to tell you to fix your code related to the tach, but I don't. Hopefully someone will come along that can help you out, but I would get all the codes cleared before I started messing with stuff that may not be broke in trying to fix your rich running condition.

[blackEagle]

I don't have any suggestions for the tach but, here are some things to try for your pinging issue:

1. Clean the MAF (dirty elements cause false signals to the EEC)

2. Clean the air temp sensor(the sensor that's on the air tube
behind the MAF).

3. Change the cooolant temp sensor (it's on the lower intake)

4. Change the O2's.

5. Check the balancer. On 94/95's it's notorious for failing which
causes false timing readings. If you see rubber sticking out or
it's wobbling when the engine is running, REPLACE IT!!!!

6. If the initial timing is too high, your chip may me adding more
timing itself causing the motor to ping.

7. Check the EGR and make sure it's working correctly.

These should narrow down the cause of the ping. Good luck.

[glenn95gt]

my suggestion, pull the chip off, and ditch it. Try a colder sparkplug. What are you running now? What is your timing set at? I stepped up to a colder plug and pinging went away.

[ribsey80]

Thanks for the help guys. I lowered my timing to 10' and the pinging seems to have gone away. The tach is still acting up on its own but it must be a connection somewhere. Because the car is brand new to me, I am realizing now that im having to put 1 liter of oil in every 1200-1500 klms. It doesnt drip anywhere and it doesnt seem to be coming out the exhaust. Could this be the valve seals? Any thoughts would be great!

[canukracer]

there is a recall on the speedo head 95v138000 this is not safety related so people don't get a letter in the mail from ford/ check the connections at the coil make sure they are clean and dry! there is more trouble shooting for the tach but try that first.