So my car currently start, idles and revs at stand still perfectly fine. Under load however, it refuses to boost. It feels like ignition or fuel cut before boost starts to kick in. I can drive the car and let revs build up slowly but as soon as you press the throttle more than a tickle it’s not happy. Any suggestions greatfully received! General Spec: 2jz-gte Vvti from an Aristo Swapped into 1992 FD3S rx7 Complete factory spec 350z 6 speed gearbox Ignition: I has new plugs, coils an leads Plugs are NGK BCPR7ES 6282 I’m getting a strong 13.5-14v fed to all 3 coils. Air: It’s running factory throttle, turbo’s and all original VSV’s MAF is mounted inside an 3” aluminium pipe I’ve checked for vac/boost leaks and found none Fuel: Factory injectors, rail & FPR FPR connected to inlet (no VSV present) Running RX7 fuel pump ECU: Factory auto ECU with neutral switch Bluetooth OBD2 reader is connected and read via Torque android ap MAF, MAP & Throttle sensor all appear to be reporting Only fault codes are gearbox related...
Has it ever run right after it was swapped? If it used to run ok, what happened before this problem started? Have you changed or swapped anything? Do you have a fuel pressure gauge in the car? If so, what does it read when you have the problem? 100% sure there are no boost leaks?
Thanks for the reply Murf! I've never had the engine in another car and the swap was completed fairly recently so I have never see it run in anger beffore. It was purchased from JDMDistro who compression tested it before shipping it out and all was ok (from memory). I don't currently have a fuel pressure gauge installed, getting an FPR & Gauge into the car is my next job. Slight issue being I won't be able to see what pressure it is running while driving... I have blasted brake cleaner over the usual areas (inlet manifold, injectors, etc) while running and not noticed any change from the nice steady idle. Also if i create a vac leak on purpose the revs go all over the place.. so i think vac leak is not the cause.
I had almost the exact same problem on a 1JZ many years ago, and it turned out to be a busted fuel pressure regulator. See if you can get another to test.
Have you done the wiring trick with the auto ecu? I have read previously you need to install a switch otherwise the ecu thinks it's in neutral and cuts all the power? Assumingly no fault codes I had a very simular thing with my jz swap and I've just sorted it with a new knock sensor wire
Yes, however it’s not even getting to the point of making ANY boost before hitting ignition cut. Also.. i’ve Ported the wastegate, so HOPEFULLY that will reduce boost creep. Ok cool that’s reassuring, i’ve Just ordered a fuel rail adapter so i can remove the factory FPR and fit an aftermarket one :-) Pretty sure i have the Neutral switch taken care of, but will double check. Only fault codes are the one’s in the picture above. Knock sensor throws an error P0330 if it is disconnected, so hopefully the fact that it’s NOT throwing an error at the moment is a sign that they are ok?!
Just fit the aftermarket FPR anyway, fit it after the standard one that's on the rail. in the line that goes back to the tank. It won't hurt anything. Only reason to remove the standard FPR is if you want to have less pressure on the rail than standard.
I can't see an IACV on your inlet manifold so I presume you are running the factory ethrottle setup? If so, it is common that if the power to ethrottle motor has been wired incorrectly then ECU will put itself into limp home mode. Won't rev over 2000rpm ish, and ethrottle butteryfly won't open more than a few degrees. Take your TB pipework off and confirm that throttle is opening 100% when WOT is given. If not then that's your problem.
The FPR i was planning to fit is rotten and leaky so need to order a new one. In the mean time took it for a drive after gettibgbthe MOT done. If I tickle the throttle it will allow me to slowly built up the revs and I can hear the turbo’s spooling. But as soon as I touch the throttle more than a tickle it missfires.
If it’s at all helpful / relevant.. the emission test was done and it scored CO% Bol of 2.888 and HC ppm vol of 377 Both of which are obviously under the limit for a non cat car, so it’s not running “super rich”.
Yeah, the fuel pressure will be low rather than high. Stuck shut rather than stuck open. I had a video somewhere of mine, lost in the depths of photobucket. Completely driveable as long as you tickled the throttle, even up to high ish rpm. But if you put your foot down it would do a weird farty missfire that almost sound like launch control holding revs (not a loud pop bang one)
That is EXACTLY what mine sounds like... like SHIT launch control! Right... that seals it.. did you replace with a factory FPR or an aftermarket one?
A stock one will work. I chased that problem for months and didnt make progress. Then when i sold it cheap because id given up piling money into it, the new owner said thats what it was, FML. Anyway, yeah a stock one should work fine.
Soooo ... new FPR fitted with rail adapter to remove the old one. With just the pump on / the car on idle the fuel pressure hold steady at 40psi. Aaaand it’s still failing to boost. Same symptoms as beffore missfires when any more than a tickle of throttle! {}
