Mechanics

ASTRO 4.3L HAS NO SPARK AND WILL NOT CRANK

1989 All Other Makes All Other Models

I have a 1989 Astro 4.3L engine 80,000 miles. A month ago the van ran fine and turned over fine. All up until I decided to change the intake gaskets. I changed the gaskets put everything back together and then tried to start the van up. The van would turn over but then wouldn't start. As I would try to start it the engine would cough as though through the air filter it was spitting gas. Some one told me it was the timing. So I then reset the timing, while I was under the hood turning the engine by hand I noticed that two wires were exposed one was the ignition switch wire and the other was some sort of positive wire but I don't no what. Mistakenly I touched the two wires and the engauge the engine. But instead of a crank I got a ringing sound as though the batteries ground wire was not grounded to the frame. Thinking nothing of it I then finished setting the timing and tried to start the the van (I taped the loose wires by the way before I tried to start it) The van would not crank when I turned the switch nor would the starter ingauge at all. I tried to bypass the start, at first I got only clunks, but then after a few tries the starter wouldn't even clunk anymore. Now the starter dosent say anything either when I bypass it. I change the coil pack, the starter the ignition switch the and ECM and still I get nothing, I don't think its the belt because as I rotatethe engine I can see that it rotates the distributer. In doing this I found out that I am not getting any spark in the distributer cap and their is no power at the spark plug wires. SO I no the problem is electrical. I am lost hope the motor is not seized but as I said no spark at the distributor. Please help. Maybe I overlooked somthing

Richard Detroit
Avatar
Poet042005
March 31, 2006.



Sounds like you might have blown a fusable link. They are located on the starter. The reason for the back fire is you still have a manifold leak and a lean mixture or severly out of time, will cause a back fire. If you removed the distributer then you may have it out of time.

Rotate the engine until the crakshaft timing mark is on #1. Verify that the rotor is pointing to #1 plug wire. If not--you have your answer.

Let me know

Tiny
Losone
Mar 31, 2006.
Well friend I checked the fusible link and found that wasnt my problem. But I was thinking the coil pack and ECM are used parts I gotfrom a junkyard, I call mysel tring to save money. I took a test light and checked the wirs that run to the starter and the coil pack it shows that their is power going through all the wires, but for some current is not going through the spark plug wire that connects the coil pack to the distributertheir is no spark at any ofthe plugs. Doyou think it could be the coil pack or the ECM or both. Last question friend is is #1 on the distributer cap the top left plug on the distributer.

Please reply Richard

Tiny
Poet042005
Mar 31, 2006.
A GM 4.3 engine is a 350 with the back two cyls missing. Everything on the front is the same.

No one cyl on the cap is at 5 o'clock with 12 o'clock to the firewall. Firing order is 1-6-5-4-3-2. Left bank looking forward is 1-3-5 Right is 2-4-6. Dist turns clockwise.

I have had some problems with that year ignition module. (In the distributer)in that year. The coils are bullet proof. Before you start pulling things apart you might want to invest in a new module, they are cheap. You will need a 5.5 mm socket to get it out of the distributer. Some of the models have a phillps head. Make sure you put the heat sync paste between the distributer plate and the module.

The ECM is a very rare failure one in 10,000. I wouldn't bother with it. Let me know

Good luck

Tiny
Losone
Apr 1, 2006.
Well it wasn't the ignition modual the van when I turn thekey says nothing at all and again the distributer has no spark but everything else gets power. I figured that the ignition modual would not stop it from turning over I have had that problem before. Anyother tips would be helpful the only thing left is to pull the wiring and see if a wire is bad. I need to find out everything that would cause this problem to see if I have missed anything Im gonna have my battery tested thats all I have notdone yet even tho its new. I truly thank U for your interest in helping me. Thanks again man Richard

Tiny
Poet042005
Apr 7, 2006.
Well it wasn't the ignition modual the van when I turn thekey says nothing at all and again the distributer has no spark but everything else gets power. I figured that the ignition modual would not stop it from turning over I have had that problem before. Anyother tips would be helpful the only thing left is to pull the wiring and see if a wire is bad. I need to find out everything that would cause this problem to see if I have missed anything Im gonna have my battery tested thats all I have notdone yet even tho its new. I truly thank U for your interest in helping me. Thanks again man Richard[/quote: f696dee39c]

I found out the problem. There was two things wrong, first I found out that the batteries ground wire was not grounded to the motor, it was resting on the frame. Second the timing on the distributer was was off and Ihad to reset it. After fixing both problems the van runs like new.

Tiny
Poet042005
May 27, 2007.