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hey guy were at dead end need any advice would be great
brand new haltech 2500
link 4bar map sensor
link flex fuel sensor
walbro 460 brand new
new 6mm fuel pump feed with 30amp replay and constant earth
first flex fuel tune was Thursday last week went through 98 tune numbers didn't seem right way to high for 98 swapped to e85 mapped corrections table with out issue started adding 98 and tuning the composition scaler % 70 60 and 50% went with out issue maybe 1 or 2 %off haltechs base 40 30 and 20 were all almost the same as 50 so we gave up was 11pm at night and after 10 hours on the dyno we decided to pick it up the next morning
next morning we went ove the cars wiring found a 6mm power feed to the fuel pump relay ran the length of the car to a empth relay holder in the engine bay so we removed all that set up a new relay in the boot triggered off the ecu and re earthed the pump thought issue solved went back to 98 (1%eth ) base map was 30% to rich went through static maped up to 4500rmp no issue pulled heaps of fuel out then started noticeing lean transient throttle then on -1.9 an 0 psi started to go lean at 2 2500 3 3500 rmp 16 17 afr added heaps of fuel realized I was almost back were I was the night b4 turned car off left for 3 hours went back to it and we were back to 10.0 afr
left over night went over tune againg up to 4500rpm again found the issue arise fuel pressure was 46psi when I started when issues was there it had droped down to 40psi figured pump was done pulled fuel pump out replace old wiring and replaced the brand new walbro 460 with a new walbro 460 went about mapping was very close to how I left it got about 15m in went to do a power run 60kmh 4th gear was about 2000rm and started the run at 18.0 after I had just finished checking everything was good same issue was back lean on transient throttle and lean as it swaped from vac to boost I had it at 11.7 at 3500rpm 18psi after wat ever happened happened we went back and went 18.0 as it I saw 2psi I got scared and got off it
again fuel preasure went from 46 with vac to 40 removed fpr pulled it apart there was no obvious signs it was at fault put it back on wound fuel preasure back up to 46 with vac still lean went 50psi still 12.7 on 8psi boost went 60psi with out touching my fuel map to get it back to 11.7 on 8psi boost but still has a lean spike 15.5 16.0 at -1.9psi and 0psi b4 it dropes down to 11.7 fuel preasure on the gauge does not drop as it comes on boost does rise when it comes on boost
tomorrow morning im going to recheck and change the fpr going to remove the 4 bar and go back to the inbuilt map sensor might evan put power fc and z32s back in to c if it stiil does it
any help at all would be great
so we managed to get a full 98 tune into her with the haltech with out fault left car on dyno idling with fane off 10 min watched afr at idle go from 14.5 to 16.0 car wont even stage for a power run wont free rev past 3000 rpm goes 29. afr and coughs and splutters
swapped from link 4 bar to onboard map sensor with no result
swapped turbo smart fpr 2000 - 800 no result
pulled haltech out fitted old power fc and 2 z32
tuned remaped the car on the power fc with out issue
first run was after chasing afrs and was hot engine 2 runs after were leaner but wat you would expect after engine cooled down to 80
worked car hard on dyno got up to 87 full power fun went fat as expected we were thinink we were onto a winner with a faulty ecu let the car idle on the dyno for 20 min tried to do 4 runs afr's went from around 11.7 to 13.3 nothing had changed in the ecu water temp was bang on 80
unplug fuel pump in car and ran engine off a 460 in a tank on the floor power supplies from car with same voltage as the fuel pump in the boot ran up with better results last night still noticing a lean out of 1.0 afr when car was allowed to idle for prolonged period of time
this morning with everything cold we ran the car up to 80 deg water and oil temps running off the external fuel set up ran richer on ever run firt run 11.2 followed by 2 runs at 11.0 beat on the car to get it up to 87 water 94 oil full run at 10.2 ish allowed to idle for 20 min leaner start of run but settled to a 11.0
at no point has the power fc stopped allowing the engine to free rev like the haltech
so we have removed the fuel pump again and are attempting to make a hard line for the suction side of the fuel pump incase we have a issue of the hose sucking in whe the temp of the fuel rises there is no visible fuel pressure drop during a run at any point
Are you running a fuel pressure sensor with the haltech? Guy on rx7club had a weird pressure sensor failure where the output shifted with ethanol content in the fuel.
Are they the gas injectors that everyone says not to use with liquid fuel due to temperature sensitivity or the new IDs?
Is the coolant/intake manifold temp influence stuff similar to what other people are running on those motors
no fuel pressure sensor
std 1600cc bosch injectors x2 sets both same issue
coolant temp and air intake temps are fine b4 it faults, get it hot and I goes rich let it idle and it goes lean but coolant temp sits on 80 81 air intake 55-60 all corrections in map are set to 0
Hey Darren, I'm going out on a limb and I'll take a guess that it's the Bosch 1600's that are your problem. You've mentioned in your original post you are running 1700's which suggests a current Injector Dynamics injector, but then subsequently mentioned Bosch 1600's which are a very different injector. If you are running the 1600's then they are known to be incredibly sensitive to fuel temp in terms of their flow capability. This could easily result in the inconsistent AFR you're seeing, however it doesn't account for the changing fuel pressure you've noted. In this regard I think you may have two separate issues since you also noted that raising the pressure didn't fix your mixture being lean.
In a multi pump system it's often a good idea to check the pressure and flow at multiple points in the system so that you can highlight if you have an issue. I'd also be checking any filters for potential blockages.
Hey guys thanks heaps for the help
We started leaning to a fuel temp issues so we put a 3/8 trans cooler in the return line and put it in a bucket of ice and fuel mixture dint move at all so we wrapped the exhaust and made some heat shielding around the tank.
Have also installed a fuel temp sensor and have set up a compensation table to allow for the heat, gonna get it to play up tomorrow and adjust the added fuel % hopefully its just heat soak from the dyno but at least with the temp sensor if it does play up on the road we wont loose a engine
Did you know you can get fuel temp from your flex fuel sensor?
Are you measuring the fuel pressure with a pressure transducer (sensor) or one of those gauges that you get supplied with regulators? Where are you measuring the pressure?
If you've tried two sets of the same kind of injector I'd be tempted to try a different brand, as Andre mentioned there are some injectors which are temperature sensitive