1994 Geo Prism... Not starting...

07-25-2015, 01:36 AM
Hi... I'm working on a 94 prism 1.6 liter. The car is garage kept and hardly ever gets drove. It ran fine about a month ago. Then a month later it will not start... this is where I'm at, I have followed the Haynes manual with all the checks. I am not getting any spark. I've check all cylinders with my spark tester and no spark. Also the fuel pump does not run unless you use the jumper wire. Changed fuel pump anyway. Does this sound like a computer problem or is there something else that will cause no spark and fuel pump to not kick in. I've checked both relays and power to fuel pump by the Haynes manual..all good. I've check power to distributor, and ohms to everything the book say to and all is good. Can't check ignition control module inside distributor because there is no check for it, even called autozone to confirm that. Car just spins over. It's an automatic also. Thanks

07-25-2015, 08:32 AM
It very well could be an ECU issue, but I am not Geo expert. I will tell you we had a similar issue with a 93 Civic last week. Pump would not prime, and injectors would not fire, but we did have spark.

Long story short after way too much testing we verified the ECU was bad by swapping in another ECU and the pump primed the instant the key was put to on, and the car fired right up.

07-25-2015, 09:52 AM
first thing to do is confirm the distributor is actually turning. if the timing belt breaks or strips some teeth off it won't. take the dist. cap off and have someone crank the engine while you look to see if the rotor turns. if its turning then you need to see if your getting 12v to the + side of the coil with the key on. does fuel pump turn on for about 2 seconds when you first turn the key on then shut off?

07-25-2015, 07:11 PM
I'm working nights so I'm not going to be able to mess with it till tuesday...I have done all checks for power to distributor and coil. I've check ohms to coil,primary and secondary. I've turned engine over with cap off and the rotor does spin. Fuel pump does not turn on at all except with jumper wire. Ive check all fuses and relays and power going to them, all is good per Haynes manual. I've been doing some research while at work. Here is what I have found out... when all test are good and you try and start car if you get no spark and fuel pump doesn't kick in and also if your check engine light is good but doesn't work like this one, even when you use the jumper wire then it's a dead ECM. I tried to check for codes and the check engine light will not light up at all, bulb is good. So Tuesday this is where I'm gonna start. Thanks guys. Keeping my fingers crossed on this one cause a new computer is $240 at autozone and they get it through Cardone.

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