Engine Strange Timing **** Happening

Are you sure that you didn't drop the dizzy in at 180* off?

When you drop the distributor in with #1 at TDC on exhaust stroke instead of compression. Did it once on an old chevy truck, started up and ran horrible, but it did run.

Putting the distributor back in and setting the timing.


You can forget about anything beyond this point if you don't have access to a timing light. You will never get the timing set right without one.


Putting the distributor back in is fairly simple. Pull #1 sparkplug, put your finger in the sparkplug hole, crank the engine until you feel compression. Then line up the TDC mark on the balancer with the pointer on the engine block.

The distributor starts out with the #1 plug wire lined up at about 12:00 with you facing it. Align the rotor to about 11:00, since it will turn clockwise as it slides into place.

Align the distributor rotor up with the #1 position marked on the cap, slide the distributor down into the block, (you may have to wiggle the rotor slightly to get the gear to engage) and then note where the rotor is pointing.
If it still lines up with #1 position on the cap, install the clamp and bolt. If not, pull it out and turn 1 tooth forwards or backwards and try again. Put the #1 spark plug back in and tighten it down, put the clamp on the distributor, but don't tighten it too much, as you will have to move the distributor to set the timing. Note that there is no such thing as one tooth off on a 5.0 Mustang. If it doesn't align perfectly with #1 position, you can turn the distributor until it does. The only problem is that if you are too far one way or the other, you can't turn the distributor enough to get the 10-14 degree optimum timing range.


Setting the timing:
Paint the mark on the harmonic balancer with paint -choose 10 degrees BTC or 14 degrees BTC or something else if you have NO2 or other power adder. I try to paint TDC red, 10 degrees BTC white and 14 degrees BTC blue.

10 degrees BTC is towards the drivers side marks.

Note: setting the timing beyond the 10 degree mark will give you a little more low speed acceleration. BUT you will need to run 93 octane to avoid pinging and engine damage. Pinging is very hard to hear at full throttle, so it could be present and you would not hear it.

Simplified diagram of what it looks like. Not all the marks are shown for ease of viewing.

ATC ' ' ' ' ' ' ' ' ' '!' ' ' ' ' ' ' ' ' ' BTC
---------------- > Direction of Rotation as viewed standing in front of the engine.

The ' is 2 degrees.
The ! is TDC
The ' is 10 degrees BTC
Set the timing 5 marks BTC. Or if you prefer, 5 marks towards the driver's side to get 10 degrees.

To get 14 degrees, set it 7 marks BTC. Or if you prefer, 7 marks towards the driver's side to get 14 degrees.

The paint marks you make are your friends if you do it correctly. They are much easier to see that the marks machined into the harmonic balancer hub.

At this point hook up all the wires, get out the timing light. Connect timing light up to battery & #1 spark plug. Then start the engine.

Remove the SPOUT connector (do a search if you want a picture of the SPOUT connector) It is the 2 pin rectangular plug on the distributor wiring harness. Only the EFI Mustang engines have a SPOUT. If yours is not EFI, check for a SPOUT: if you don’t find one, skip any instructions regarding the SPOUT
Warning: there are only two places the SPOUT should be when you time the engine. The first place is in your pocket while you are setting the timing and the second is back in the harness when you finish. The little bugger is too easy to lose and too hard to find a replacement.

Start engine, loosen distributor hold down with a 1/2" universal socket. Shine the timing light on the marks and turn the distributor until the mark lines up with the edge of the timing pointer. Tighten down the distributor hold down bolt, Replace the SPOUT connector and you are done.

The HO firing order is 1-3-7-2-6-5-4-8.
Non HO firing order is 1-5-4-2-6-3-7-8

The crank rotates twice for everytime the cam rotates once. #1 compression stroke (upward travel), #2 power stroke (downward travel), #3 exhaust stroke (upward travel), and #4 intake stroke (downward travel). Per every cycle, the #1 cylinder is at TDC twice. So, if your #1 is at TDC at the end of the exhaust stroke, before the intake stroke, and you drop the dizzy in, it would be at 180* off. I know it doesn't make sense that an engine could even run like that, but I have witnessed it first hand. Sorry for the confusion, and I hope that you get it straightened out.

You did remove the SPOUT plug when you checked your base timing, right? To me, it sounds like you're getting the reading with the advance, or the inductive pickup on the timing light is on the wrong plug wire.

tca7291 said:

The crank rotates twice for everytime the cam rotates once. #1 compression stroke (upward travel), #2 power stroke (downward travel), #3 exhaust stroke (upward travel), and #4 intake stroke (downward travel). Per every cycle, the #1 cylinder is at TDC twice. So, if your #1 is at TDC at the end of the exhaust stroke, before the intake stroke, and you drop the dizzy in, it would be at 180* off. I know it doesn't make sense that an engine could even run like that, but I have witnessed it first hand. Sorry for the confusion, and I hope that you get it straightened out.

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Lol not sure I would have apologized to anyone that called me "no help" due to their own ignorance but .... Not sure why the wiring swap makes it start better, engine can idle fine with the timing all screwed up, seen it a ton but things sure go south once a load gets put on it. I do know that a harmonic balancer can slip and give erroneous timing readings, possibly that is whats happening there.

Also had a problem one time putting my engine together with the timing 180* off but mine was making a popping sound through the intake. Took it out, turned it 180* and had no problem. Just because your piston is at the top doesn't mean it's top dead center.

TDC and BDC refer to piston orientation, not to timing or cam orientation. On a four-stroke engine, the piston is at TDC and BDC twice between firing. Good luck.

Not twice between firing, it fires every other time.

If you follow jrichker's procedure, and it does not work after checking the ignition timing marks, how about a cam timing issuse? It used to be a loose timing chain could skip a tooth or few with a backfire when trying to reset the distributor. I have not heard of it happening for a while, but it sounds like a possibility. It could be worth pulling a valve cover to see if things are going at the right time, but the real tell will be the dots on the gears.

89nor-calgorilla said:

that makes absolutely no sense what you said. I am dropping the dist in with cyl#1 piston at its peak upward travel. TOP DEAD CENTER.
This is not my first rodeo and this place is no help. Taking the car to a real mechanic. Thanks anyway.

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89nor-calgorilla said:

I am getting check engine light while running but sometimes shuts off. Totally confused. Maybe bad computer?

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Computers seldom fail, usually it's a bad sensor or wiring. Here's how to find out...


Dumping the computer diagnostic codes on 86-95 Mustangs

Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

Here's the way 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. You watch the flashing test lamp or Check Engine Light and count the flashes.

Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.





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.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

Some 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.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, and clutch (if present) is pressed to the floor, and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Your 87 won't have a working Check Engine Light, so you'll need a test light.
See AutoZone Part Number: 25886 , $10



Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see Equus - Digital Ford Code Reader (3145) – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30

Symptoms sound similar to timing set at 10 after instead of before. I did that recently myself.

Hmm.. was it a bad pump or FPR or did you just not set the pressure correctly? LOL happens

89nor-calgorilla said:

that makes absolutely no sense what you said. I am dropping the dist in with cyl#1 piston at its peak upward travel. TOP DEAD CENTER.
This is not my first rodeo and this place is no help. Taking the car to a real mechanic. Thanks anyway.

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Wow... You shouldn't be doing any engine work if you can't understand this concept... It makes perfect sense...go ask a "real mechanic"... He will tell you the same thing..

http://en.m.wikipedia.org/wiki/Four-stroke_engine
Go to this link. I think this will help you understand what he was saying.