Rotary Ronin

Hey guys, I just bought a 1991 turbo II the exact model I’ve been wanting. I was told that it has a stuck open injector, I researched the problem but didn’t find an exact match of the symptoms only because the people who were told they had this problem, never mentioned it driving and boosting normally. the car will start normally, but sometimes you have to hold the pedal down while turning the key (the guy told me for air since it was already flooding from the injector), when it starts from cold it idles fine on the high-speed idle, then when it warms up it drops to normal operating temperature and kills, it can be kept alive by tapping the pedal. you can drive it normally it just doesn’t want to idle, it also has a bit of a misfire sometimes he said. the motor supposedly has a street port, a fuel cut eliminator, and an fd3s fuel pump on it which I was told was bigger than stock. my question is, is it a stuck open injector? and if so, should I get stock injectors, or should I upgrade them to bigger to accommodate the fuel pump? if so what size injectors would be best? and could the fd3s furl pump be the culprit of all my problems? Hopefully someone can help me out so that we can get this rotary back on the road XD!

RotaryRocket88

iTrader: (7)

It could be just as the owner says, and you would need to send out the injectors to be cleaned (www.witchhunter.com $18 per injector). Typically injector issues can be solved with this process. Technically, you could just get the primary injectors cleaned, but you might as well do all 4 at the same time.

An FD fuel pump will flow just about the same as a stock TII pump at low pressures (idle), but it has a ~20% better flow rate at high pressures (boost). An S5 will likely have the fuel pump resistor / relay, which reduces pump voltage under low load conditions anyway as a fuel saving measure, so don't worry about the pump affecting idle.

Lastly, if the owner is using a fuel cut defenser (FCD), they've probably turned the boost pressure up too. If there's anything less than upgraded 720cc secondary injectors and some sort of fuel control, the motor is likely about to die. 10+ psi on stock injectors will lean out and detonate, and the FCD will make ecu make the timing adjustments based on false pressure data. Look into rtek ecu options (www.pocketlogger.com) for much better control for relatively little $.