It is very unlikely that the engine's timing chain has "jumped a tooth".
Do the simple stuff first...
Dump the codes and see what the computer says is wrong…
Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.
See
http://www.troublecodes.net/Ford/
OR
See
http://www.mustangworks.com/articles/electronics/eec-iv_codes.html
IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.
Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.
Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.
For those who are intimidated by all the wires & connections, see
http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.
Or for a nicer scanner see
http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $35.
Post the codes & we will help you fix them.
Don't put away your paper clip just yet...you'll need it to do a cylinder balance test...
Cylinder balance test:
Warm the car's engine up to normal operating temperature. Use a jumper wire or paper clip to put the computer into test mode. Start the engine and let it go through the normal diagnostic tests, then quickly press the throttle to the floor. The engine RPM should exceed 2500 RPM's for a brief second. The engine RPM's will increase to about 1450-1600 RPM and hold steady. The engine will shut off power to each injector, one at a time. When it has sequenced through all 8 injectors, it will flash 99 for everything OK, or the number of the failing cylinder such as 22 for cylinder #2. Quickly pressing the throttle again up to 2500 RPM’s will cause the test to re-run with smaller qualifying figures. Do it a third time, and if the same cylinder shows up, the cylinder is weak and isn’t putting out power like it should. See the Chilton’s Shop manual for the complete test procedure
Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.
See
http://www.troublecodes.net/Ford/
OR
See
http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See
http://www.mustangworks.com/articles/electronics/eec-iv_codes.html
Use an automotive stethoscope to help isolate the noise. Don't have one and the auto parts stores don't have one for less than $8-$10 or so? Use a long screwdriver against the bottom of a empty tin can. Put the blade end where you want to check and the handle against the bottom of the tin can. Put you ear over the opening and you'll be amazed at what you can hear. Move around in the engine compartment, putting the blade anywhere there is a bearing area or a cover over a moving part. When the noise gets loud, you have found the area where the problem is.
Once the codes have been dumped and fixed, it's time to do some simple preventive maintance. Replace the fuel and air filters.
If you have a
K&N, and Mass Air, clean the MAF element. The MAF element is secured by 2 screws & has 1 wiring connector. To clean the element, remove it from the MAF housing and spray it down with electronic parts cleaner or non-inflammable brake parts cleaner (same stuff in a bigger can and cheaper too).
If the spark plug mileage is over 50 K or is unknown, replace them. I like Autolite 24's for stock heads. Look closely at the spark plug wires for damage, loose connections or burnt spots. Run the car in the dark with the hood open. Look for sparks or glow around the spark plug wires. Replace any wires that show these symptoms.
Do all this first, and then think about a compression test, vacuum test & fuel pressure test. All of these tests require some tools that you may not have or be able to rent from your favorite auto parts store.