Paulusc44

Ok cool, I know theres no switch but was wondering if maybe the ECU could sense max voltage output from the TPS or if the TPS had a max voltage contact or something like that.. Obviously not though haha Im simply going to apply + Temperature to the 2 pin Coolant temp sensor before cranking to see what effects this has on starting, have just done a resistance test on it and all working fine, surprising how flat the cranking pulse width variance is but there is a quite a difference between say 0 and 40' C.. Should give me a good idea on whether or not the pulse width is to large at startup.. Only have limited time to spend on it as Im at uni and have to travel between Citys to work on her

For sure yeah can throw the multi meter over em, just wanted to see if anyone knew before I possibly throw waay to much fuel in there + Im a Autotronics student and have not been told about this as of yet, was watching an American compression + leak down test and they stressed to depress the throttle all the way to the floor to disable the injectors rather than removing the EFI fuse, pump relay etc.. Just thought it was interesting and wanted to know if it was universal and if Nissan used the same idea

Hey all, I have a factory ECU with tuned EPROM and RX7 550cc injectors that run the same resistance as factory RB20DET items.. Just a quick question, is it true that the injectors are 100% disabled if the throttle is at WOT (Max throttle/wide open throttle) during cranking/startup? I know this is the case for some vehicles and some aftermarket ECUs depending on tuning etc, but cant find any info for the S1 RB20DET/RB25DE? At the moment I believe my cranking pulse width is too big and want to double check this.. Cheers

I know the modern fuel-injector has a far improved idle (low pulse width and duty cycle) Im just not willing to write them off as "old heaps of shit"?? Tuned correctly, Idle isnt bad with older injectors, (remember were talking late 80s/early 90s JECS here) and as previously discussed, spray-pattern/atomizing of fuel at high duty cycle and pulse width is fine. My point is, this is a S1 RB25+T running a factory-like setup to achieve a simple 200-220 KW on low boost, not a built RB26 aiming for 400KW for example, spending $800-$1000 on injectors is foolish when one can get a set of S5 RX7 550cc injectors and dyno tuned Nistune board for $1200?

Cheers GTSBoy.. Was originally going with a Nistune board as I can get them for a really sharp price here in NZ.. But due to study Im forced to sell the 32 and clear up funds.. Most people would sell the car as is but im one of those anal pricks and want top dollar haha

The build was done on a planned budget so I only had x amount to spend on each item, 6 x 666cc or 1000cc bosh injectors go for $660 & $780 respectively here, IDs are no cheaper.. I picked these up for $280 shipped, have you actually thrown a pair of 20 year old JECS into a injector bench tester before? Hardly "old heaps of shit"..

Recently fired up my S1 R25DE+T, engine has received alot of work over the last 6 months including larger turbo, injectors, fresh gaskets throughout etc.. First time starting with new setup and eprom tune. Runs pretty good, still have a few little things to sort but its all there. The engine now runs 550cc RX-7 injectors with walbro 255 LPH pump and adj pressure reg. Its sometimes hesitant to start, I believe its putting too much fuel into the engine whilst cranking, I deleted the cold start valve when I did the new setup but am now thinking of putting in back in, I have done a resistance test on it and its perfect according to my R32 workshop manual, will this aid in supplying less fuel to the engine on start up? Or put the engine in open loop and put even more fuel in? basically, Will this help the engine start? Any info/help is great as start up is really the only issue, it currently has no O2 sensor but I will be putting a new NTK item in over the next few weeks with new downpipe, vehicle has only idled/lightly revved so far. Cheers

I can imagine over time the check valves in factory fuel pumps would leak.. It just surprises me as this is a 6 month old genuine walbro, and the check valve was working fine in it last time I checked.. (Rail held pressure etc)

Are there EFI fuel pumps without check-valves in them? I thought all modern fuel pumps had a check valve?

Cool, just wanted to check, I actually ended up using the pump under regular conditions (using factory relay) dont know if you remember my question I asked you about a week back about my fuel pump? Thinking the relay was dead I powered it directly with 13 v, ran it for a few seconds, and then re-connected the factory connector just to double check it wasent working and.. woolah the thing worked again without being directly powered and has been working fine ever since? Also, am I correct in saying fuel pressure should be held in the rail at all times? (ign on and off) I can set my FPR to whatever pressure I like (45 PSI in this case) and it will stay at that pressure with the fuel pump running, but when I turn ign off, the pressure begins to drop off quite sharply? Im thinking diaphram/valve in the FPR itself? (Its new/under warranty) Obviously this doesent effect running but still..

Hey all, Recently went to fire up my rebuilt S1 RB25 which has had some decent upgrades carried out on it over the last 6 months.. Found the Fuel Pump wasent running (Walbro 255 L.P.H) So simply hard wired it in without using a relay and got it to work.. My Question is, under constant power can I still control fuel pressure and run it for a short time? ( I have a Japanese Adj. FPR fitted) Is amperage flow suitable? Cheers

Yeah man was pretty much at that point of things, was wondering if I could by pass the 4 pin relay control circuit for the signal? This would effectively run the pump the entire time I know but its saves me a semi-dodgy bench test? (as fuel pumps can be) Like, feeding signal and power directly from the battery and then earthing the pump directly on the chassis? Any ideas? And just to get back to the negatively switched components, true, but you would be amazed at how many European manufacturers have attempted to use positive switching in the past haha

Haha Just went to fire up the thing, have done an entire range of mods over the last 6 months without starting it up.. no puel pump? Ive got 12+ volts at the + pump wire? Im thinking ign. signal? Is there a way to by-pass this directly from the battery to check? Fuel pump is a 12 month old Walbro 255LPH

ok cool, cheers, Ive got a cheeky fuel pump question too if you feel like helping out? haha

So judging by what your simply saying here I can join my 2 earths (signal + chassis) and then route them to the R33 S2 "earth" pin? Im fully aware what a 5 volt reference signal does, and on alot of later model vehicles a 3 pin MAF or MAP is far more common, which leads me to believe I can simply join them? Im just double checking