help rough idle, missing

[speed demon]

I have a 1988 mustang with a AOD tranny (A4LD). Recently it has been missing, had a really rough idle, had absolutly no power (won't go faster that 20, but changes gear)and has hard starting, especially when warm. I check the timing, the spark plug wires, the coil, for vacuum leaks and replaced the spark plugs. When i replaced the plugs (with platimun), the idle got smoother, and you didn't notice the missing as much. Also when i try to see if there any codes in the computer I don't get anything at all, not even code 11. Any suggestions would be appreciated.

[J.M]

I'm not a pro, but it sounds like you could have a fuel distribution problem. Try checking your fuel line. You could have crud buildup.

***2000 3.8L***no mods at this time.

[StellarSaleen]

Did you ever figure out the problem? I have a 1993 4 cyl. with the exact same symptoms. Put the accelerator on the floor and its like pushing a ton of bricks. Seems kinda smooth when in park but you put the engine under a load and it starts to shake like crazy. I changed the plug wires, plugs, coil packs (distributorless in 93), and found the timing to be set at 12 degrees. Im baffled! I took the cylinder head off and it looks like the number one cylinder hasnt been hitting. Im replacing the head but I still dont think this is going to be the end of my problems.

[PNYXPS66]

Has anyone thought about correctly checking the timing on these cars? You must check the timing WITHOUT the emissions control computer hooked up (this is BASE TIMING and the specs are located on the VECI label located inside the engine bay). If Stellar Saleen's base timing is at 12 degrees, then when the computer adjusts the timing, the cylinder isn't firing until almost 24 degrees after top dead center! That means there's no compression to make power. This will also cause missing and other problems. I'm sorry if you bought another head Stellar, but it wasn't worth it unless you were overheating and/or losing coolant through the tailpipe; having the old head magnafluxed and checked for cracks (about a $10 job at most machine shops!).

Good luck guys.

[StellarSaleen]

What is the 4 banger timing set at from the factory? I've looked everywhere and cant find it. The label under my hood is apparently gone or invisible one. Ive yet to buy the new head so Im going to take mine to the machine shop for an inspection. The only cylinder thats not firing is number one. When I remove any other plug wires the engine bogs out. But when I remove the number one plug wire it doesnt miss a beat. Please help me!

[PNYXPS66]

Usually the label was located on the fan shroud right in front of you on the top, or on the underside of the hood, usually to one side near the front. It provides all the setting inforamtion for your vehicle. If this label is in fact gone, you can do two things: 1) call you local ford parts department or service center and see if they can get the settings from ford. Have your full VIN number with you when you call. They will need this to Id your specific car. 2) Obtain a Haynes (Clymers or Chilton's are other manual makers) manual that includes your particular year of pony. It will instruct you on how to disable the emmissions system to set the base timing. The $12-$20 you spend on the manual will save you the first time you use it in frustration and paying someone else to fix your car.

(I am assuming you know the basics on setting timing here.) If the information is not available, then you must start blind. When you set your timing, start at 4 degrees after top dead center(ATDC). Reconnect the emmissions system and test the car. If it runs ok, or better, take the car to a service center to get the timing set correctly.

Although you have replaced the ignition system, have you tested to see if you are getting spark to the #1 plug? If not, the problem may be in the coil or the wire even if they are new! Swap plug wires and see if the problem follows the wire. If so, there's you culprit. Same for the coil packs; reverse them (I believe there are only two) if the problem follows the coil pack, replace it.
Let me know how it goes.

[PNYXPS66]

I have an 88 also. First, IMHO (In My Humble Opinion) you are checking the codes wrong. Get a Haynes manual that will show you how to ground the system properly; you dont want to fry your computer. Check your ignition cap for cracks and carbon trails. The note that platinum plugs made the firing smoother suggests there may be a resistance problem in the ignition system.

A fuel distribution problem cannot be ruled out, change your fuel filter and run some hi-test fuel with some fuel system cleaner. I recommend OUTLAW fuel system cleaner. To me, it's worked the best. Also, with the engine running, pull the vacuum line off of the fuel pressure regulator. This will flood the engine with fuel and cause it to run much worse, or shut off if it is working. If it's not, there will be little or no change in the engine performance.

Another idea for fuel is to stand at the back of the car while it's running, and smell for raw fuel. You will know it because it will smell like a fuel station, and your eyes will burn. Don't do it too long, you could asphyxiate yourself.

Give it a shot.