Worked great, car running lot better

bought this truck and it had the stock coils and plugs in the trailblazer at 162000 miles but new ngk plugs and these coils and the randon misfire was gone she runs great now and mpg wen up from 12 to 20mpg
p0301,p0302,p0305 code but they all reset after the swap of parts, came with the grease too.

A very good deal, if one or two need replacing, order a set and replace them all. Be sure to replace your plugs too, but locally source those at a part store. Flawless operation, very pleased.

Short Story, I bought my Trailblazer the better part of a decade ago, it had about 204,000 miles on it when I bought it, still rocking the stock Delphi Coils which I assume where original to the truck, the whole time i've owned this truck I have gotten around 13.8-14.5 MPG (which is downright HORRIBLE and far below what i've seen other people say they get), the single BEST tank average, which was an all highway drive, was 16.5 MPG and I had NEVER been able to hit that again. I tried EVERYTHING I could think of, ran fuel system cleaner, changed Fuel Filter (done that twice in the last 40k miles), replaced Spark Plugs, even replaced the VVT Solenoid since it had Oil in the Electrical Connector (a sign of failure) and NONE of that gave me more then a tenth of a MPG increase.

Fast forward to about 3 weeks ago, i'm out on a drive and when returning to town the truck starts feeling like it's misfiring, knowing how these trucks are known to leave you stranded on the side of the road from a bad coil pack I hopped onto Amazon as soon as I stopped in town to grab dinner and ordered this set of coil packs and then drove home and parked the truck for the next few days. Once the new coil packs arrived I installed them and took the truck for a quick "spin around the block", Not only was the misfire GONE, the throttle response was improved noticeably, so I decided to take the truck instead of the car for the vacation I was leaving on the next day to really put these coils to the test, well nearly 900 miles and 4 tanks of gas later I averaged 20.3 MPG HIGHWAY, the 2 best tanks of that 4 tank drive averaged 21 MPG, that driving was on relatively flat ground with little to no traffic and the cruise control set to the speed limit where the other 2 tanks involved moderate mountains and some traffic on the drive down.

I can tell it takes less RPM to maintain the same speed than it used to before changing the coil packs, this Truck has over 246,000 Miles on it now and it gets 20+ MPG HIGHWAY just like they did when they where NEW, I am shocked at the difference these coils have made to this basically 20 year old truck.

The only real question is how long will they last for and thats the only reason I can't give these coils 5 stars, I just can't vouch for how long they will last, i've got about a 1,000 miles on them so far, but at this point it's all GRAVY in my book, given the current cost of gas these coils have already paid for themselves in the fuel savings I have seen and they have solved the issue of poor gas mileage that has haunted me from the beginning on this truck, so even if they fail early they have told me what I need to do to fix this trucks gas mileage, if I end up needing to invest in a quality set of coils I will, or I could just buy another set of these to keep around as spares in case any go bad.

Been almost 1 month and no issues to report. Works as intended and great price.