Camaro4Lif3

Hello all and thanks for taking the time to read this.... I would of searched for other similarities that others might have had, but I don't think this is a "Regular Issue" that people might have.

So I upgraded my motor with PRC Stage 2.5 5.3L heads P/P from TSP with a Torquer V3 Cam. Also upgraded to Kooks LT's. Also upgraded my fuel injectors to FAST 35lbs. Everything else is stock.

Went to NewTech in the Bay Area to get a Dyno Tune. 1st thing I've heard is my RWHP was WAY to low for all the mods I did to my engine. I'm sitting at 381rwhp with all the upgrades. Next thing is about a month or two after my tune, everything has ran very well. One day I get into my car with a cold start... let it idle for a few minutes to warm up, and back out and start to make forward momentum. As I'm trying to accelerate giving it gas, the car is SLUGGISH like I was not getting enough fuel OR like it was miss firing. As I tried giving it more gas it still was SLUGGISH very very jerky. Like a light switch what ever was the issue the car just goes because of where I had the gas peddle at like as if I was trying to do a burn out and it responded with no issues.... I came down and it repeated the process. Different gears, different RPM when it happened, so I couldn't pin point when it would start. The issue what ever it was, did it another 8-10 times in the next hour i was driving it. Next day, start her up... and like the issue never happened it has ran smooth since then.

So we are about 4 months later today. And the experience was almost the same feeling but not as brutal. It went from a dead stop to about 2K RPM and it felt kinda like the same thing... like it wasn't Firing on all 8, the exhaust sounded way different as well. I've talked to the Tuner in the past and he said everything is the best he could of done for my setup.

I'm not throwing any codes and I still haven't ran a test on the computer to see if its anything fuel related. Has anybody had any experience with something like this? To happen only one day a few months ago, go away for 4 months and it SOMEWHAT does it again?

Skraight

iTrader: (3)

Did the CEL flash at all when it was happening?

I had this issue and chased it for a few months, as it was intermittent and would go away then come back.

After replacing plugs, wires, fuel filters, hooking it to a scanner, etc. etc. It was my MSD coil packs.

Mine also did not throw any coils as the misfires were intermittent.

Camaro4Lif3

No check engine light happened or is on when it happened both separate times. Spark plugs and MSD wires recently changed about 5K miles ago

02ls1gun

I dont want to send you on a wild goose chase but, I cant help to wonder; doesnt the fuel pump run on throttle position?? Its almost like you hit the gas.....nothing happens and it stumbles....then wam the fuel gets there and you take off

Camaro4Lif3

Another great idea.... that is something that is on my check list. I'll test the car tomorrow and see if the symptoms are still there or if they receded for the time being.

Camaro4Lif3

So as an update, fired her up today, took it up and down the street and It "fixed" No idea what it is. Checked wires and plugs and they looked good (After I ran the car up the street to make sure It wasn't the plugs and wires so I can rule it out) I'm looking into another Dyno tune... looks like another $600.

garygnu

have you changed your fuel filter ?take your plugs out and test them with a meter .clean your IAC ,and the MAF.check all wire connections for any water .are all your wire grounds tight ?maybe hook up a fuel gauge to test the fuel pump for correct pressure .