8 replies to this topic

[leej323]

Hey All,

I just did a complete overhaul of my ignition system in my '86 RX. Replaced spark plugs (Bosch Platinum), ignition coil, distributor cover, and wires. I fired it up just a while ago and it feels like I have half the power I had before I changed everything.

Does the ECU have to adapt to the new setup or did I just do something wrong? I double-checked all connections and everything is snug.

Thanks in advance!

[4WDFrenzy]

I'd highly suggest getting ditching the Bosch Platinums and install some NGK plugs. (NKG #: BPR6ES-11) I have had past experience(when I worked at Autozone) with Bosch plugs and I know for a fact that you can't use them in every car. So engines run like crap with them installed. They could be causing misfire in the cylinders due to the wrong resistance, which would give you your power loss problem. So, since it is the cheapest part(in all the parts that were replaced), I would start with the plugs. Unless you removed & reinstalled your distributor during your maintanence session, I'd be inclined to believe that it is a spark plug issue. Hope this helps.

Patrick

[leej323]

I'll definitely look into different plugs first. Thanks for your input.

Edit: Nope, I didn't remove the distributor as a whole. I only changed the cap.

[4WDFrenzy]

Cool. NGK plugs seem to work the best in our motors.

Oh and before I forget, you may want to make sure that it isn't a bad spark plug wire. Sometimes they can get crimps in the wires when they are packed into the boxes if the wires are long. So if you have any kind of warranty on them, exchange them with a new set just to be safe.

Patrick

[leej323]

Hmm, well I swapped in some NGK's and the engine is still misfiring.

One thing I noticed when I took out the Bosch Platinums was that one plug was black while the others still looked new. Could this be due to a bad wire?

[4WDFrenzy]

Hmm, well I swapped in some NGK's and the engine is still misfiring.

One thing I noticed when I took out the Bosch Platinums was that one plug was black while the others still looked new. Could this be due to a bad wire?

It is a good possibility. I'm assuming that the car was running okay before you changed the wires? Try reinstalling the old spark plug wire from that same cylinder and see if the misfire issue goes away. If it does, then you know that you have a faulty wire. If not, there may be a problem with the position sensor in the distributor, which would really be craptacular.

Patrick

[leej323]

It is a good possibility. I'm assuming that the car was running okay before you changed the wires? Try reinstalling the old spark plug wire from that same cylinder and see if the misfire issue goes away. If it does, then you know that you have a faulty wire. If not, there may be a problem with the position sensor in the distributor, which would really be craptacular.

Patrick

Yes, the car was running alright engine-wise. The reason I did the maintenance was because the ignition coil was spitting sparks (I believe it had never been replaced since the car was built... 190,000+ miles). Another member here suggested I swap out the rest of the ignition parts while I was changing the coil.

I'll try using the old wire and see what happens.

Edit: One more thing. I noticed the engine sounds more like it did before the maintenance when I took out the Bosch plugs and replaced them w/ NGK.

[leej323]

Well, it seems my wires weren't plugged in correctly... had the wire for the wrong cylinder plugged into the wrong distributor.

[4WDFrenzy]

Don't you just love it when it turns out to be something simple?

Patrick