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Hi,

I have recently turbo converted my RB25DE R34 with all standard R34 parts and have a hesitation fault with it. 

When I am accelerating, the car seems to feel like it's hesitating and sometimes seems sounds like it's hitting the limiter earlier than it should (popping out of the exhaust). 

I have already replaced the plugs for NGK BCPR7ES plugs which I fitted at the time of fitting the turbo and have since replaced the coil packs with brand new genuine Nissan coilpacks. 

The car is running the standard GT-t ECU at the moment (have heard many people say that there's run fine on it until Nistuned) and just has a HKS cat back exhaust, aftermarket front pipe and a HKS induction kit tuning wise. The fuel pump on the car is a standard GT-t fuel pump, but not sure whether it will be running fine without having the fuel pump control module and dropping resistor that the GT-t has? 

 

Any help is much appreciated. ?

 

Thanks 

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Plugs are too cold for stock, should be Bcpr611 or similar!

also are you sure the new coil packs are “new”

I bought reconditioned Nissan coils and they were rubbish, caused misfiring, engine light and slip light! Stranded me at shops ?  Got refunded! Quick smart!

check afm, timing, and use stock neo ecu!

injectors should be fine if not Gtt ones just for driving off boost/low boost 

how did I go? ?

I'm running a stock NEO non-turbo AFM without any problems. I'm using GTT injectors and stock GTT ECU. At first I kept the NGK BKR5EIX iridium plugs that I already had before the turbo conversion. Not ideal maybe but they worked ok. I've been running the conversion for 3 or 4 years.

Recently I did have a misfire that felt a bit like hitting the rev limiter. I found some Splitfire coil packs on a spare engine I have so fitted those. At the same time I changed to NGK BKR7ESC-11 that one of the tuners here in the UK recommended for my +t and that misfire is gone.

Thanks for the replies. 

The coilpacks I bought from AutoExtreme, so know that these are genuine new Nissan ones. 

The engine timing is spot on, along with the ignition timing which I am running at 15degrees BTDC on the Plus-T. 

The injectors and intake manifold are stock GT-t Neo ones, so am assuming these are fine. 

I am currently running the standard GT-t side mount intercooler, so not too sure if this along with the higher compression will be running higher engine temps. I've got a Blitz return flow FMIC on order at the moment. 

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