S4 s5 hodge podge mess
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S4 s5 hodge podge mess
Bought my first turbo rx7, someone else’s project, a mix and match of parts and had been trying to get it running. Back story is it’s a 1987 turbo 2 but has a S5 engine, I’ve actually gotten it to run now but after about 1/3 throttle it totally falls on its face and dies unless you let off the throttle. It’s running a mix and match of s4 and s5 parts including s4 crank angle sensor, s4 lower and upper intake manifold, s5 throttle body (I’m only using the narrow side tps), s5 injectors (I’ve spliced in the correct harness plugs and deleted the s4 injector resistor box), s4 knock sensor and control box, s4 front cover with omp deleted, s4 ecu, s4 afm, s4 map sensor, deleted the thermowax, and deleted the air bypass. It runs great after letting it warm up a bit, crispy throttle response as long as I don’t go past about 1/3 throttle. My question is, is the cam that drives the tps different between s4 and s5? Seems kind tips related to me. Do I have to use the s4 throttle body and tps with an s4 ecu? Am I just an idiot and missing something else super obvious?
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
totally possible its something basic, but if you had an S4 throttle, that would be a nice thing to test. if it is on the right TPS the S5 one should be close enough
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