Bought 6 used Mazda Rx-7 injectors from rx7club.com, two from three different people. Two came flow tested at 570 ish cc, the other four I had flow tested and came to 670 cc (I attribute it to being a cheap ass shop...they probably use a fluid with a different specific weight than gasoline). They were the exact same part numbers stamped on the injectors...no way I bought four funky ones from two different people.
I took off upper IC pipes, nearby vacuum lines, three banjo bolts for the fuel rail, and the coolant line going to the ISCV. My Dad pinched that coolant line off with vice grips so it wouldn't leak...line is still good. Did not take the TB/TPS/ISCV off, I have skinny hands. Lubed the o-rings and seats up with a dab of 5W30 oil, took the old ones out, shoved the new ones in, connected everything including LIPP AFM. Took three tries to fire up but it ran like a champ for a wee bit.
After a while it would start stumbling...the idle would lope ~50 rpm up and down, wouldn't stay steady, sounded 'bumbly' and smelled pretty rich.
Skipping forward, I'm tired of typing:
-Drives relatively fine at speed. Won't stall at speed. Vacuum levels on my AEM Tru-Boost read lower than before (usually at 65 mph with 0 throttle, it would be -21 or -22 downhill, now is -19 ish). Car pulls fine at speed. Vacuum levels are also lower at idle or low speed than they should be, but only by a few. Sprayed carb cleaner around the injectors, no noticeable pickup. Sprayed water and looked for mist, nothing. Took the line off of the brake booster going to the intake manifold, pressurized up to ~10 psi with and without throttle open, couldn't find anything and was very thorough over by the EGR valve. Checked IC pipes and intake for leaks, nothing. Started loping worse at idle...~100 to ~200 up and down, occasionally stalls on the downswing. Getting harder to start....very lopey and rich, but would smooth out with accelerator and a few seconds. Now stalls occasionally slowing down for a stop sign or red light...will lope, car will jerk forward on the upswing (obviously) and eventually either stall on the downswing or even out.
Checked codes...three: o2 sensor, coolant temp sensor, boost pressure. Fixed the o2 sensor wiring properly (never depinned connectors before, eesh), bought a new coolant temp sensor. Swapped in my old AFM electronics box...no difference. Haven't had much time to drive it since, as every time I start it it lopes up and down and stalls within a few seconds. I can get it to drive if I want to by brake boosting a tiiiiiny bit to get it into drive and get the car going. Once I get up the street the stalling symptoms go away.
As it sits now: lopey idle upon starting most of the time, hot or cold, usually stalls promptly. Once I get driving the symptoms mostly go away but occasional stalling and lopey idle at low speed occurs. Exhaust smells pretty rich sometimes (no cat).
Sorry for the wall of text, I wanted to be thorough. If I had to guess I'd say I'd check the resistance values for the TPS and ISCV to make sure they're good, but it seems odd they'd break RIGHT after I install the injectors and AFM. And AFAIK the wires and connectors are good, but I obviously can't see into the harness itself so if it's broken down the line I guess it sucks to be me.
Any ideas? :icon_razz
I took off upper IC pipes, nearby vacuum lines, three banjo bolts for the fuel rail, and the coolant line going to the ISCV. My Dad pinched that coolant line off with vice grips so it wouldn't leak...line is still good. Did not take the TB/TPS/ISCV off, I have skinny hands. Lubed the o-rings and seats up with a dab of 5W30 oil, took the old ones out, shoved the new ones in, connected everything including LIPP AFM. Took three tries to fire up but it ran like a champ for a wee bit.
After a while it would start stumbling...the idle would lope ~50 rpm up and down, wouldn't stay steady, sounded 'bumbly' and smelled pretty rich.
Skipping forward, I'm tired of typing:
-Drives relatively fine at speed. Won't stall at speed. Vacuum levels on my AEM Tru-Boost read lower than before (usually at 65 mph with 0 throttle, it would be -21 or -22 downhill, now is -19 ish). Car pulls fine at speed. Vacuum levels are also lower at idle or low speed than they should be, but only by a few. Sprayed carb cleaner around the injectors, no noticeable pickup. Sprayed water and looked for mist, nothing. Took the line off of the brake booster going to the intake manifold, pressurized up to ~10 psi with and without throttle open, couldn't find anything and was very thorough over by the EGR valve. Checked IC pipes and intake for leaks, nothing. Started loping worse at idle...~100 to ~200 up and down, occasionally stalls on the downswing. Getting harder to start....very lopey and rich, but would smooth out with accelerator and a few seconds. Now stalls occasionally slowing down for a stop sign or red light...will lope, car will jerk forward on the upswing (obviously) and eventually either stall on the downswing or even out.
Checked codes...three: o2 sensor, coolant temp sensor, boost pressure. Fixed the o2 sensor wiring properly (never depinned connectors before, eesh), bought a new coolant temp sensor. Swapped in my old AFM electronics box...no difference. Haven't had much time to drive it since, as every time I start it it lopes up and down and stalls within a few seconds. I can get it to drive if I want to by brake boosting a tiiiiiny bit to get it into drive and get the car going. Once I get up the street the stalling symptoms go away.
As it sits now: lopey idle upon starting most of the time, hot or cold, usually stalls promptly. Once I get driving the symptoms mostly go away but occasional stalling and lopey idle at low speed occurs. Exhaust smells pretty rich sometimes (no cat).
Sorry for the wall of text, I wanted to be thorough. If I had to guess I'd say I'd check the resistance values for the TPS and ISCV to make sure they're good, but it seems odd they'd break RIGHT after I install the injectors and AFM. And AFAIK the wires and connectors are good, but I obviously can't see into the harness itself so if it's broken down the line I guess it sucks to be me.
Any ideas? :icon_razz
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