TimF
10+ Year Contributor
- 821
- 7
- Mar 14, 2011
-
Aurora,
Illinois
For the past few weeks now I have been trying to figure a acceleration issue with my car. I have the block out for a while and replaced all the gaskets and seals, timing components, and new plugs and wires. My car is an auto but I swapped out the 390cc injectors for 450cc and currently have ecmlink (only temporary to monitor my car, and I plan on using a stock 5 speed when everything is sorted out). Other mods on the car are 3in exhaust, fmic, 2.5in piping ngr bov recirculated, 14b turbo (connected straight from j pipe to wastegate) walbro 255, and aero fpr. When I got the car back together and running I started driving it to realize it is not properly accelerating. In ecm link im logging hp and torque (I know there not accurate) but noticed during regular driving they would fluctuate up and down like a heart rate monitor. If i go WOT my car will pick up, then die off, then feel it pick up again for a couple hundred rpm, then die off again, and then pull hard. My turbo is spooling up, and there are no counts of knock when that is happening (although I do see a small hit of .4-1.7 sometimes in higher rpm ranges). I was initially told it was a fuel system system problem so I replaced the filter, didn't make a difference, then tried stock fpr, didn't make a difference either. after that I swapped in the 255 and went back to aero still the same issue, then for the hell of it i swapped in another aero fpr of my other car and still did not do anything. My fuel pressure is set at 37psi for the injectors. I also have no boost leaks, they where all found and patched. ECM link is also reading 35-45 gm/rev at idle which i know is supposed to be around 24-26 gm/rev and my base ignition timing bounces between 3.9 and 7 degree. but when i GO adjust it and ground it it stays perfectly at 5 degrees. I really want this car cleared up so I can sell it but I am now unsure of what else it could be.
