I've seen a lot of people return those plugs or throw them out... garbage... stay with stock ac delco's, or go with NGK's...

I've seen a lot of people return those plugs or throw them out... garbage...

stay with stock ac delco's, or go with NGK's...

My recommendation of OEM (AC Delco) plugs is based purely on personal experience. Good performance, smooth idle, and longevity. Also, it's what I see recommended, so I believe most people are experiencing the same thing. This is one of the few areas where aftermarket has not come up with a better solution.

Don't waste your money on them. I tried them once on my Sunfire figuring I would spend the cash on 4 cylinders first before trying 8. Well, my Sunfire has 366,000Km on it and had developed a random miss... figuring I haven't changed plugs forever, I tried the E3's. When I took the coil assembly off, I noticed a large crack in the coil pack cover. Figuring this was the cause of my miss, I changed it out along with some new plug boots and the E3's. Well, the miss persisted.. so on comes the troubleshooting. I checked the fuel pressure, OK, the regulator was leaking a little, changed it, TPS had a bit of a dead spot in it.. changed it. Cam position sensor tested out of spec, changed it... in the process, the cam position sensor was only $14, so changed it at the same time. Still had the miss. Tested the coil packs, one tested a bit weak.. changed both. Still had the miss. A friend had a spare ignition control computer, tried it.. still had the miss, so I continued to use my old one. After about 2000Km of screwing around to figure out what the heck is going on, suddenly my car lost all power. Felt like it was running on 2 or 3 cylinders. There was hardly any vacuum at the throttle body. Somebody suggested with the KM on my car, maybe the catalytic was plugged up or broken. Took it to the muffler shop.. the max backpressure they tested was 2PSI meaning that wasn't it. Finally, and old school mechanic told me to get some factory AC plugs back in there. Well, I was at the point of taking it to a shop so I figured what the heck... put them in.. got in behind the wheel.. hit the key... the SECOND it fired, I knew all was fine again. I could instantly hear better vacuum at the throttle body. All was not lost on the swap out of other parts though. I commute to another city on a daily basis and my milage suddenly increase by about 15%. I've put about 30,000Km on the car since that incident and it's still running great.

In short, the E3's... don't do it.

I have had great performance with the E3's in my lawn equipment, etc. Less fuel consumption, a little more power and easy starting. But, I would not put them in a modern vehicle.

I ran E3s in my 96 4.3. it ran awesome and passed emissions with better numbers than the delcos. i'm thinking about running them in my new truck.