judasentinel

@brett: I understand that they both should go back to the same level when the car switched off....and I fixed it, yay!! However, I don't feel my ignorance in the matter requires me to take the car to a pro at this stage. Yes, if I am unable to identify the real cause and cannot fix it, will I do that. @aaron: The limp mode generally doesn't allow the car to rev past 3000 rpm or thereabouts. Mine revs just fine. The slight jerking only happens in gears 3-5 in that rpm range and once I am past the 3000-3500 rpm range, it runs great. In addition, the car doesn't do it in that rpm range in second or first gears, possibly because there is a higher level of load. I am feeling that this might have something to do with the load levels or the TPS settings? I have had many R32s and never had to deal with this issue with them. Wondering if there is something different in the R33s. I admit that since this car was already modified, and I am still discovering the extent of the mods, I might not know everything about her. I just drove her to work today, and other than the jerking around 2500-3500 rpm in gears 3-5, it was great. All 6 cylinders seem to be firing, and the car is building boost well. I will try to clean the MAFs soon and see what change that causes. Thank you both for your inputs. Please do keep the suggestions coming in. Munib

I wasa thinking that the persopn who I bought the car from in Japan had two boost gauges to measure the boost pressure before the intercooler, which hardly makes any sense. So I wonder why two gauges in the first place? Assuming your point about one auge measuring pressure before and the other after, the intercooler, is valid, how does it correspond to the shuddering, in that the difference between the two gauges is much higher than it was, say, a week ago? I am wondering if it has ANYTHING to do with the possibility of onw of the turbos not getting enough exhaust pressure, so it is spinning slower, and therefore, producing less pressure. If that were the case, it would point to one or more cylinders not firing properly. Or is the above totally wrong? I would rather it be a dirty MAF, than a faulty set of coils or a timing belt issue (skipped a tooth or two). The idle is also slightly rougher than a few days ago. Could this be related to poor combustion/ignition in a cylnder? I appreciate any and all inputs.

Never occurred to me that the AFMs could cause the readings on the boost gauges to be different or the BOVs to go off one after the other. Do you think that could be an issue? When it is idling and I give it gas, one boost gauge jumps to 0 and the other goes a little futher up. And when I turn the car off, the boost gauge that goes to 0 goes back to 0, while thge other one stays much lower. Arent they both supposed to go back to zero pressure (no vacuum or boost) when the car is off? Could this be caused by a leak or faulty coil(s)? How is what I am describing (the shudder and jerking) different from turbo shuffle? Or is it?

I have a 1995 R33 GTR, and recently, I have seen it develop an issue relating to the turbos. This is what has been happening: Light throttle, the car shudders and jerks a little bit, but when I accelerate hard, the jerking goes away. This only happens around 2000-3500 rpm range, and only under light throttle. If I let go of the accelerator, the shuddering goes away. I have two boost gauges, possibly one for each of the turbos. One shows a slightly higher reading than the other, which makes me wonder why it is so. When I bought the car a few months ago, both gauges used to show almost the same reading. The two BOVs seem to go off in sequence. One goes off first and then a second later, the other goes off. This wasnt the case a couple of months back. I am stumped as to what the cause is, how to look for it, and what to check. Could someone please help? Thanks Munib