I went to a local dyno day today to get baseline numbers before I begin my H/C swap. I feel like car is really down on power. I did think the car was a bit sluggish but this was kind of disappointing. I'm now thinking I should find out where I'm losing power before I begin this project.

2001 Trans Am M6 37k
SLP LT
Borla adjustable cat back
POTZ TB
K&N intake

On their mustang dyno it made 236 HP on the first run (4th gear). It felt like it took forever to complete the run. After it was over the owner comes over and says try this next one in 3rd gear. I felt kind of embarrassed.

If I can figure out how to upload the dyno graph the bottom lines were a 4th gear pull and the top lines were a 3rd gear pull.

What do you guys think? Where should I begin. I pulled a plug but I don't know much about reading them. From research the ground strap look nice with the timing mark pretty close to where it should be. Porcelain was only gray half way around you can slightly see in one picture. Volt meter on the cluster a needle width above 13. I'm not really sure what to do from here.

 

Sorry didn't realize I posted this in the internal section by accident... I'm sure it's and external issue. Still learning my way around the site.

 

Did you check the plug wires and make sure they were connected all the way on both ends? No SES light I assume? Anything sound abnormal?

 

Haven't checked all the wires. It did throw a code last year once and briefly this spring. I had it checked last year and it was exhaust related. The car sounds great, idles smooth. I had a 355 lt1 before this one and that one ran much better than my current.

 

Do you have a scan reader with a Data Logger. Or you can get one of those Wi-Fi dongles for the OBD2. So you can check the fuel trims and the O2 sensors and see what they're doing.

 

I don't

 

You can get one off ebay relatively cheap. Better than chasing your tail around and doing different things and guessing. Or you can unplug the MAF see if it runs better.

 

Go to O'Reilly or some place and they should let you scan in the parking lot.

 

I talked to the owner of the shop today. He thinks since it idles nice and doesnt run rough that something is going on with the way it's tuned. I might just go ahead and swap H/C have it tuned and see where it's at. Don't really wanna waste the money on having it tuned when I'll have to have it redone soon.

 

Mine idled fine and didnt run rough either. Coming to find out bank2 was calling for 20% more fuel. It was just down on performance and I could feel it. Ended up being my pvc hose came undone I had a vacuum leak hooked it backup and ran like a champ. But its your car don't take advice from people that have been there and experience simlar issue.

 

I don't mean to be unappreciative of the responses because I do appreciate all the information on this forum. I will be checking wires and hoses tonight and giving it a good once over. Just kinda of looking for some obvious problems that some may have. This wasn't really in the plan.

 

So tonight I checked wires and gave it a good once over. Noticed the rear of the driver valve cover had a light coat of oil and also the barb on rear passenger cover. Just decided to tear all the PCV tubes out and I'll replace them tomorrow with a new PCV valve on the driver cover grommet. I'll let you guys know how it goes tomorrow night.

 

When is the last time you did all the little things--- fuel filter, deleted the cats, wires, spark plug wires, cleaned the air filters, etc

 

Spark plugs and wires don't look very old. I have an extra fuel filter for it I'll switch for the hell of it if this don't do anything.