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GTS-T bucking/hesitating before it builds boost Greets I've owned my GTS-T for about a month now and have experienced bucking on and off since the start. The weekend I picked it up it rained buckets and I chocked the poor performance up to weather, and set out to investigate once the weather passed (on the drive home the car would also want to stall occasionally as I came to a stop). The weather was clear the following day, and a visual inspection turned up a torn fuel line leading into the fuel filter. Replaced the hose and took it for a test drive- same issues, the car would want to stumble and stall at idle and buck under load. I work sales at a VW/Audi tuner shop and some of the technicians are keen on helping me get the car sorted at the shop, so after a few fits and backfires as the car warmed up that Monday, it ran smoothly on my way into work. I should note that it blew the boost signal vacuum line off the intake manifold during these fits...easy fix. I drove it off and on to work for a couple weeks with no issues. Last week on my way into work it started to buck and break up again (at the end of my 30-minute drive). I had less than a 1/8 tank of gas and wondered if the fuel pump was picking up crap that was sitting in the bottom of the tank. Fill up on the way home and add Lucas Fuel Treatment to the tank- no change. Took a day off work last week to put some time in with the car and found the three wires on the coilpack harness were either broken or frayed badly right at the connection on the top of the coilpack cover. Replaced the harness with a new one from Wiring Specialties on Saturday and after a few times stalling out it finally idled correctly. I took it out and drive it spiritedly for about 10 minutes and it ran really, really good. I was feeling pretty good about my R32 at this point, so good that I decided to take the wife out to dinner in it later that day (the car sat for about 6 hours). We get in and it will crank and crank and crank but not start. Great. Let it sit overnight and it fires right up. That brings us to today. I drove the Skyline into work today and halfway into my drive it starts to buck again. It happens before the engine starts to build boost and I can keep it from happening if I am light on the gas pedal. I've been spoiled with OBD2 diagnostics in the VW/Audi world but am a bit lost with my Skyline. I have read that hesitation/bucking out of boost may be an indicator of a bad MAF? I have a Z32 MAF and adapter harness ready to go in, and I have a new fuel filter and coilpacks/plugs at the ready, but I am not keen on throwing parts at a problem. Could it be a fueling issue not related to the MAF? Anything else I should pay attention to? I am sorry for the wall of text, but I wanted to make sure I covered every detail. Thanks all Mike

Slight hesitation when coming on boost - R33 GTST Hi all. Since I've had my Skyline I've noticed that often when coming onto boost (from 1/2 throttle or more) from a reasonably low rpm (under 4k) there will be a slight delay in the power coming on. It's a 1997 GTST, only engine mods are pod filter, front mount, yellow jacket coilpacks and MBC. Fresh BCPR7ES spark plugs gapped to 0.8mm. I'll watch the boost gauge and it will make 10 PSI (my set boost level) but won't really shove for another second or so. It kind of stumbles for a second before it remembers that boost should equal power. It doesn't splutter like with buggered coilpacks, it just kind of doesn't respond properly for a moment. It's not the delay from the boost itself that I'm feeling, there's definitely a delay between boost and power. That's not right, surely? The only thing I've really tried is replacing my fuel filter and cleaning the MAF with some electronics cleaner. I'm thinking either MAF or fuel pump. Any ideas?

So any help appreciated guys, There's countless posts on misfiring on this site and I've viewed most of the ones I've found, to no avail. Engine details: RB25DET S1.5, ECU is Haltech E11V2, running a MAFless tune, Garrett GT3582R, Upgraded Intercooler, GFB manual Boost controller, Tial EWG 63mm, Nismo 740cc injectors, 3BAR MAP sensor, Bosch 040 fuel pump, Sard adjustable fuel reg (with gauge (set at 55psi) HKS Oil cooler and remote Oil filter, Splitfire Coils, NGK Copper plugs gapped at .8 with 21KMs on them. So car developed a missfire last week, over fueling, hesitating at all operating temps (biggest from TPS 0 to >2) from startup to shut down with a rich and lean pops in exhaust, surging during acelleration and cruising. Checked usual culprits in order; Coils, Plugs, Tune re install, Vacume and hoses, Fuel Reg, Compression test, Injectors Flow tested and inspected All okay, TPS sensor, Coolant temp sensor, Air Temp sensor, MAP sensor, related wiring, AAC valve, replaced Fuel filter, and ECU checks out. Nowe I havnt done the CAS, as I was under impression that a faulty cas will cause problems with starting, and it starts like nothings wrong. The BOV has been on for 4 years (was on car when I got it) and never had an issue with it before) have checked to make shure Diaphragm in Fuel reg isn't totalled and it's all fine. And no it hasn't had an o2 sensor on the exhaust (ecu) since acquiring it. The air fuel mix at idle is around 10.8:1 richining on throttle depress. All sensor have been tested with Multimeter and viewing on the Ecu both are in sync. Cars in Red Center Nats in a month so would like to have it run by then. Any help appreciated

Hello, I have this issue and im suspecting something is up with the diff/LSD. Whenever the car wants to lose traction it starts hesitating be either either a left, right turn, over a bump, from stationery up a hill turn where the wheel starts losing traction it starts bogging down but at speed it hesitates like ABS lol I have a FPR and it shows fine pressure from the fuel pump and it does it also when the tank is full so i dont think its to do with fuel. car is R33 GTST

hey there guys have been a long time reader but first time posting i have recently had my 96 S2 R33 with RB25DET at the tuner after a bunch of new mods he was having an issue with the car hesitating for a second or 2 when the throttle is jabbed quickly.. making it feel quite un responsive and laggy ( throttle is fine otherwise, just has to be increased slowly.. its most noticable down low or when giving it a quick rev in neutral) he believed it to be a TPS issue so i got a new NISSAN TPS the same as what i had in the car. which surprisingly was a S1 TPS (obviously with a S1 Throttle body too, installed by previous owner) with the extra plug and fly lead hanging off it.... he managed to tune it ok but it still has the same issue - just to clarify ive got it plugged into the fly lead plug not the one on the bottom of the sensor.. i believe this is the signal plug so this is a two pronged question 1. other than the way the the TPS mechanicaly connects to the throttle body are the sensors both the same electronically? 0.5 - 5v DC? - if so it shouldnt matter that i have a S1 sensor on a S2 motor 2. when i tested it i seem to be getting 0.6v at closed throttle and 3v ish at WOT.. i believe its ment to be 0.5 - 5v from what ive read on SAU.. i have hesitated to adjust it as dont want to screw up the tune i have just had... but is this likely to cause the problem i am having.. or is it possible he has compensated for these incorrect voltage readings in the ECU (VIPEC) or something? any assistance would be greatly appreciated.. and ive been searching for a couple hours and couldnt find anything that answers this completely.. so sorry if this is a repeat post thanks caleb