ECM issue?

03 vue, 3.0 motor. NOT the Honda V6. ECM has been replaced twice in 10 yrs. car had elec issue. Dash lights, poor performance. Shop said alt was shot, battery was shot. Elec issue fried elec system? Replaced, ran bad, misfire. Pulled coil packs, oil was in plug wells, bad VC gaskets, changed plugs. Still misfire on 1-3. Changed coil pack, misfire is on 2-4 now. Towed to friend of owner who is mechanic. Checked timing marks, ok. New alt, battery, both coil packs, plugs, VC gaskets. Ran ok for 60 sec, started chugging again. Shop said there is a way to verify if fuse block has corrosion/grounding issue with scan tool but also thinks ECM is bad again. Seller says sell it. I can throw in a used ECM but how do I verify if it is an electrical/ wiring issue?

I know a few people who have had Saturns of this vintage and they’ve all had chronic and unsolvable electrical problems. They’ve al gotten rid of their cars. The only honest recommendation I can offer is that you do the same.

Sorry, but if you keep this car I strongly suspect you’ll never get it running right. You may find the attached of interest.

I don’t doubt that there are Saturns out there without problems, but if you have one with problems they were probably built in at the factory.

Not mine. But my kid has one. The ECM swap is easy, as the security relearn is also easy. But will it fix issue? If it does which means it is an ECM issue, how long will it last? 1 week, or 2 yrs? I can get it for cheap and fix it and certainly don’t plan on keeping it for 10 yrs. but I do want to drive it for 6 months. I like the vues and the bad trans CVT ones are on CL all day for $1000 or less. I can buy it cheap, try and fix it, and if I fail, just sell it for my low cost. I don’t look at it as a hobby. I just like to fiddle with cars.

Does this have the Opel V6 . . . ?

Yes Opel motor. It ran fine till the elec issue showed up. Went from running fine to not running.

Have you tried cleaning or replacing the EGR valve to correct the chugging issue? I doubt the ECU is causing the issue. Make sure the ground connections in the engine area are clean and making good connection.

Chugging was term seller used. I looked at it yesterday. Great shape. Tires are 75% at least. New brakes, rotors, calipers. Motor will start but dies in 1-2 sec. Almost like a fuel cutoff issue which is same as ECM security fuel shutoff? Original owner. ECM has been replaced twice. Last was 5 yrs ago. I think owner is damn familiar with ECM no run issues? They misplaced lien release card as loan was paid off 7 yrs ago. Going to get replacement from bank.

It should be pretty simple to find out if the security system is causing the shutdown issue by making some voltage checks at the proper spots. Intermittent electrical problems, particularly with the power to the ECM, can fool one into thinking that the ECM is bad if they don’t check things out correctly.

If it dies in 2 or 3 seconds it’s a passlock problem. Do you have another key to try? There is a passlock relearn procedure.

Intermittant chugging at idle always make me wonder if the EGR is sticking or kicking on when it shouldn’t. If you can get it to chug but not stall, try manually turning on the egr. If it doesn’t stall, that would indicate the EGR function is turning on when it shouldn’t. Note that simply disconnecting the EGR system inputs might not keep the EGR from activating, as carbon build up can cause it to stick in the “on” position irrespective of the inputs.