in my 87 trans am i have no spark, ive read few threads on this and ive replaced just about everything, distributor, rotor, cap, coil, control module, the distributor i got two used ones from the salvage yard for a total of three different ones ive used, thinking it was the pick up coil. I stillget no spark out of the ignition coil even tho there is power comming to it from the ignition. What else am I over looking here?

 

Does the rotor turn when you crank it, the timing chain could be broken.

 

Ill definantly look into that this morning, thanks. anything else you could think off the top of your head?

 

Not at the moment sounds like you've done everything but cpr.

 

lol, im about to try that too, maybe if i take jumper cables to the engine and yell clear i'll get lucky =P . As long as im not mistaken, the spark is a completely independant system and doesnt rely on the cpu to produce a spark, meaning there's no sensor or relay etc that can stop the spark other than the things ive already replaced. I swear this car is about to make me drink at 9:30 in the morning

 

In order for the distributor to be completely isolated from the ECM, the 4-wire connector needs to be open. If fuel injected, the injectors won't fire with the connector open, but for troubleshooting a no-spark condition that is OK. Prevents flooding the engine too.

Instead of cranking the engine for troubleshooting, can wire the distributor up while out of the engine. Then ground the distributor body to the engine block. Can use a clip lead, or a length of wire and some hose clamps.

Then key-on and spin the distributor by the gear.

RBob.

 

ok, we have spark, but now something else is happening, the engine wont start onits own, however if i spray starter fluid into it it fires up instantly and stays on, ive even driven it up and down the street and it stays on and revs fine, but when i turn it off it doesnt want to start again unless i spray the fluid into it. then if fires up again and stays on again. is there something about the distributor that tells the injectors to start firing? if sohow come the injectors start working after the engine is already started? TPI btw

 

Make sure that the fuel pump is coming on at key-on, engine-off for two seconds. If not then oil pressure needs to build before the pump will turn on and provide fuel.

A brief crank of the key should also restart the fuel pump for a 2-second run. The ECM does this when it sees reference pulses from the distributor. The ECM also does the 2-second pump run at key-on.

Failure of this pump run can be a bad ECM or a bad fuel pump relay or bad wiring.

An '87 TPI also has a cold start injector. But this isn't needed/used on an engine that is warmed up.

RBob.

 

I ruled out the fuel pump problem by running a constant 12v feed to the pump months ago, so if ignition is on then the pump is on constantly. I can still hear the pump running constantly when i turn the key on so i know its working. i thought about the cold start injector but like you said that injector isnt sed when the engine is warmed up, after driving it temp was at 190, when i turned it off it wont turn back on unless with the spray. i was wondering, could i have hooked up the control module wrong? im sure i put the pins right but if i mixed the two connectors that connect the pick up coil to the control module could that stop the car from firing up? Just thought id ask before going back in . but yet if the car stays on after i spray the fluid in doesnt that mean that its all hooked up ok?

 

If the wires between the pickup coil and module are reversed, the timing will retard once the ECM takes over. It will still crank at the base setting. Can check this with a timing light.

RBob.

 

Messed with the car again today, she still wont start on her own. But when i sprayed the starter fluid in she started and i drove her for a good 20 miles flawlessly. I even floored it on the highway and she performed fine. But when i turn her off she will not start. Imma open another tread with this problem, but is there anything else you can think of?

 

At this point I would check the fuel pressure. Make sure that it is at 42 - 47 psi at key-on, engine-off. Note that the pressure should hold for a while.

RBob.

 

i know its not that cause there are two pumps in the car, right after the inline filter under the car i have installed a MSD High Pressure Electric Fuel Pump. 43 gph at 40 psi or 282 lbs/hr. Only draws 5.4amps. Both pumps are on at key-on. When you put your hand around the rubber part of the fuel line under the hood you can definantly feel the strong flow of fuel.