Swap runs, won't rev
#1
Full Member
Thread Starter
Swap runs, won't rev
I am helping a friend with his swapped car (S5 motor in S4). We got the car running but it runs rough and when you step on the gas quickly it will die as if its getting flooded out. As far as I know all the proper parts are installed. ALL of the vacuum lines have been removed along with the air pump though. Would putting that back on make it run much smoother? He told me he was driving it and then it lost power and died. Compression is good and is getting spark. Any ideas would be helpful.
#3
Full Member
Thread Starter
They don't. The original plan was to go through an rpm switch to activate them before my friend bought it. If we can atleast get it running decently he's planning on going LSx route for a "because racecar" vehicle, which was my friends plan for it. I know he still has the rats nest but I do t remember seeing any solenoids that I remember the engine having unless I overlooked them.
#5
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#7
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Thread Starter
It still has the stock harness, but IIRC the injectors are S5. But what I meant in m previous post is would switching the secondary and primary injectors have made a difference. Or are they the same flow?
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#8
Moderator
iTrader: (1)
S5 have high impedance injectors and S4 have low impedance so you can't use high impedance injectors w/a low impedance resistor box. You need to check to see if you have the resistor box as part of the injector circuitry or not. If you do then unplug it and bypass it.
https://www.rx7club.com/attachments/...lackyellow-jpg
https://www.rx7club.com/attachments/...lackyellow-jpg
Last edited by satch; 10-07-13 at 06:17 PM.
#9
Full Member
Thread Starter
S5 have high impedance injectors and S4 have low impedance so you can't use high impedance injectors w/a low impedance resistor box. You need to check to see if you have the resistor box as part of the injector circuitry or not. If you do then unplug it and bypass it.
https://www.rx7club.com/attachments/...lackyellow-jpg
https://www.rx7club.com/attachments/...lackyellow-jpg
#10
Mazda Tech
iTrader: (4)
Depends. The BAC should never be removed although some remove it during an emissions removal. The air pump is pretty important on an s5 cause it actuates the aux ports. Im not sure but there may be a solenoid on the rack for VDI actuation as well.
Both of those would be easy to rig up with an electric air pump, relay and rpm switches.
Both of those would be easy to rig up with an electric air pump, relay and rpm switches.
#11
Full Member
Thread Starter
Depends. The BAC should never be removed although some remove it during an emissions removal. The air pump is pretty important on an s5 cause it actuates the aux ports. Im not sure but there may be a solenoid on the rack for VDI actuation as well.
Both of those would be easy to rig up with an electric air pump, relay and rpm switches.
Both of those would be easy to rig up with an electric air pump, relay and rpm switches.
#12
Sharp Claws
iTrader: (30)
need more info, like is this a complete swap with S5 AFM, harness, injectors and ECU?
usually i would start by checking the TPS, then move to codes for oil metering pump, then on to checking fuel pressure and for vacuum leaks. faulty grounds being the main culprit but the most difficult to get to.
usually i would start by checking the TPS, then move to codes for oil metering pump, then on to checking fuel pressure and for vacuum leaks. faulty grounds being the main culprit but the most difficult to get to.
#14
Full Member
Thread Starter
need more info, like is this a complete swap with S5 AFM, harness, injectors and ECU?
usually i would start by checking the TPS, then move to codes for oil metering pump, then on to checking fuel pressure and for vacuum leaks. faulty grounds being the main culprit but the most difficult to get to.
usually i would start by checking the TPS, then move to codes for oil metering pump, then on to checking fuel pressure and for vacuum leaks. faulty grounds being the main culprit but the most difficult to get to.
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