Hesitation on the highway
Posted: Sun Jun 29, 2003 9:02 pm
My setup:
I have a 95 Integra B18C1 (P72 ECU) with a greddy turbo running at 7psi (with intercooler) with 550 injectors. I have Honda stage 2b (datalogging). I have an after market fuel pump (255 lph) along with after market fuel rail, filter and regulator and the stock ignition system.
The Problem:
It all started shortly after adding the turbo to the car. I can't really put my finger on any one thing because I upgraded several items on the car at the time the turbo was added. Basically what happens is when I'm on the highway simply cruising between 60 and 80 mph (3000 to 4000 rpm), every once in a while the car will jerk like the engine was miss firing. This also sometimes happens during part throttle acceleration, but not a frequent. Other than this problem, the car runs great. At full throttle under boost the car is fine. One thing I have noticed while logging is that when this jerk happens, the O2 sensor goes lean for a fraction of a second. Also I should also point out that when it does happen I am not under boost.
What I have done:
I've been troubleshooting this for a while now. I've gone through the whole ignition system, replacing plugs (cold ones, normal ones), wires, you name it and have not come up with anything. So recently I've turned to the fuel system. For a while I was running 310 injectors that came with my turbo kit but I recently upgraded to 550s but that did not solve the problem. So next I turned to the fuel regulator. I had a B&M one but I moved the AEM model and I also upgraded my fuel pressure gauge (just to be sure). Still, no luck. I should mention that after each of these upgrades I road tuned the car with a wideband (Stage 4, my buddy has all the programming stuff). Even during the tuning session the car would jerk every once in a while on the freeway but there was really nothing in hondata that was a smoking gun other than the fuel going lean for a split second (Again, it real
ly only happens when I'm on the freeway and I press on the gas a little bit). Also, closed loop or open loop it still has the problem.
Solutions?
Well, I almost out of them. It's really a shame because again the car runs great otherwise. This has just been a naging problem I would like to get rid of. Any help would be appreciated.
Thanks
I have a 95 Integra B18C1 (P72 ECU) with a greddy turbo running at 7psi (with intercooler) with 550 injectors. I have Honda stage 2b (datalogging). I have an after market fuel pump (255 lph) along with after market fuel rail, filter and regulator and the stock ignition system.
The Problem:
It all started shortly after adding the turbo to the car. I can't really put my finger on any one thing because I upgraded several items on the car at the time the turbo was added. Basically what happens is when I'm on the highway simply cruising between 60 and 80 mph (3000 to 4000 rpm), every once in a while the car will jerk like the engine was miss firing. This also sometimes happens during part throttle acceleration, but not a frequent. Other than this problem, the car runs great. At full throttle under boost the car is fine. One thing I have noticed while logging is that when this jerk happens, the O2 sensor goes lean for a fraction of a second. Also I should also point out that when it does happen I am not under boost.
What I have done:
I've been troubleshooting this for a while now. I've gone through the whole ignition system, replacing plugs (cold ones, normal ones), wires, you name it and have not come up with anything. So recently I've turned to the fuel system. For a while I was running 310 injectors that came with my turbo kit but I recently upgraded to 550s but that did not solve the problem. So next I turned to the fuel regulator. I had a B&M one but I moved the AEM model and I also upgraded my fuel pressure gauge (just to be sure). Still, no luck. I should mention that after each of these upgrades I road tuned the car with a wideband (Stage 4, my buddy has all the programming stuff). Even during the tuning session the car would jerk every once in a while on the freeway but there was really nothing in hondata that was a smoking gun other than the fuel going lean for a split second (Again, it real
ly only happens when I'm on the freeway and I press on the gas a little bit). Also, closed loop or open loop it still has the problem.
Solutions?
Well, I almost out of them. It's really a shame because again the car runs great otherwise. This has just been a naging problem I would like to get rid of. Any help would be appreciated.
Thanks