schiavoneus

92 beretta 3.1 liter engine automatic. I have no spark at any cylinder and am not sure what the best option is to begin looking at. Plausible that all 3 coil packs failed at the same time. (2 were replaced last year). codes were checked and only get code 12 (all clear). checked Haynes schematic and noticed an amplifier in line with the coil packs between ECM and coil packs. Wondering if this could be the problem? Any help would be greatly appreciated. Trying to decide if I should spend the time and money or torch the car.

Blue Bowtie

Welcome Aboard!

First, the likelihood of three coil packs failing simultaneously is very low. It is more likely that the device which fires the coils has a problem (the Ignition Coil Module, or ICM).

Secondly, a Code 12 is not defined as "All Clear" or "All O.K." That is a common misconception being propagated around the internet and in McDonald's parking lot BS sessions. A Cede 12 is defined as "Distributor/Ignition Reference Pulses Missing" which means that there are no reference (firing) pulses at the distributor or ICM (depending upon engine) while the ignition is turned on. This code should ALWAYS appear when the ECM is placed in diagnostic request, since the ignition power is on but the engine isn't turning. That is likely why there is confusion over it's actual meaning.

Third, if there is only a Code 12, that means that there are no ignition reference pulses. That could also be the case while the engine is being cranked, thus the lack of any other error codes. Test the ICM output transistors, and verify that there is a crank Position Sensor signal while the engine is cranking. If one of those is missing, there will be no spark.

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schiavoneus

Hey thank you so much for your help. I really appreciate it. Thus far, we have determined that the center coil pack is bad AGAIN. However, I am still perplexed as to why there is no spark from the other 2. Last time, the car ran (with misfires) We are now going to try to get to the Ignition Coil Module and will probably have to replace that as well.

schiavoneus

okay, we replaced the bad coil and the ignition control module...STILL NO SPARK. It was worth a try though. At this point I think the next thing would be to replace the crank sensor? Any other input/ideas?--I'm stumped at this point.

Blue Bowtie

The ICM should have been tested before replacement. The same with the CKP (crank sensor). Don't simply replace parts without some diagnosis. Your repairs will get very expensive and time consuming that way.

If you study the ignition system schematic, you will see the test points. A simple multimeter is all that's needed to test most items.

This LINK Might be useful if you don't have a manual at hand. The two pieces of information at the very bottom of the page pertain to your vehicle.

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schiavoneus

Thanks for the advice and help. It turned out to be the crankshaft sensor. I replaced that and she fired right up.

loosenut74

crankshaft sensor controls spark..... camshaft controls fuel timing.... in all 60 degree V-6's... i.e. 2.8, 3.1, 3100, 3400, 3500, 3900....