ROTAHREEEHEHEHE

I am troubleshooting the fuel injection system on my 2004 RX8 and need to know if the fuel pump resistor can cause excess fuel to be injected if its out of spec. Its rates 0.32 ohms and mine reads 0.4 to 0.5 ohms. Is that out of specification enough to cause a problem? The manual states it should be 2.16 Ohms. SO not sure where to start on this. When I pull my spark plugs there is a ton of gas on them. It idles poorly too. I just changed the sparkplugs and before I fire her up I was considering changing this part to see if it helps at all, after spending $80 on new plugs I REALLY don't want to foul them up again. I have been getting misfire on rotor one before I changed everything. So far I have new coils, new wires, new spark plugs. Car has CAT & AIR pump delete. And for some reason the heater is disconnected on the front oxygen sensor? There has been a lot done to the car, seems to have an engine from a 2009.. Any input would be appreciated.

Loki

iTrader: (1)

Fitting an engine from a 2009 into a 2004 is a ton of work and can cause all kinds of issues. Are you sure on that one?

One simple thing to try is resetting the long term ECU memory: key to ON, tap the brake pedal rapidly 20 times. You should see the oil guage sweep once if successful. This is supposed to be done when changing engines or ESS sensors.

As for the resistor, I think that might be the wrong tree. That resistor is on a switch and only active at low speed to quiten the pump. Having higher resistance would only slow it down more, the opposite of what you're thinking.

Are the coils wired to the correct spark plugs? Can you get fuel trim data from the ECU? Any codes? Possible vacuum leaks?

Were all 4 plugs wet or only one of the rotors? That might help figure out if the root cause is specific to 1 rotor, like a leaky injector or common to all like a vacuum leak.

The 3500rpm number is meaningful, the SSV opens then. Possible it's stuck open?

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ROTAHREEEHEHEHE

Ok so I have been told that the Blue plate on the engine means that is was rebuilt? I get these codes that I am working on fixing. P0301- rotor 1 misfire, (front plugs were wet with gas and carbon fouled when removed, the rear ones were dry but had carbon on them, I had cleaned them up a bit and put them in to see if they would get dirty again), P0125- excessive time to enter closed loop (not sure if the thermostat has been removed), P0031- Ho2s oxygen sensor heater circuit low (for some reason the heater circuit is disconnected?), I get a U0101 Communication with PCM lost. and P0455 EVAP gross leak/no flow (AIR pump and has been removed and vacuum line to solenoid plugged. And CAT has been Gutted) It was setting a P0300 before I did the 20 break stomp but now throws a P0301.

I have replaced all the coils (are wired to proper plugs and ECU connections), wires, and now spark plugs. I am pretty sure there is a ton of carbon build up in the chambers too. The Air cleaner has been replaced with a make shift cold air intake to eliminate what was once the old air intake box which was chopped up LOL. I bought it as an auto shop project car..

The SSV seems to move freely, but there could be a vacuum problem that I haven't located yet. At first start it seems to run ok then it quickly starts to sound funny. Car has 129,500 on her. And is a 2004 AT.
Here is a picture of the blue plate.

Loki

iTrader: (1)

Well, step one, you need the stock intake on there. Chopped up whatever is going to screw up the MAF sensor's readings and cause idling problems.
As for the plugs being wet... if it's just the one rotor that's wet, see if there's a leaking injector on that rotor.

Not having a working O2 definitely isnt helping.

ROTAHREEEHEHEHE

Thank you for the advice, after a quick drive it still is about the same as before I put the plugs and wires in. Going to try and return it to stock as much as I can. Hope the junk yard has a few of these I can get parts off of. I get no hot air from my heater core, and my power steering isn't working all of a sudden. These sure are fussy cars lol. After you do the 20 break stomp reset, do you have to let it idle to operating temp to relearn the idle?
<~(CB)~>

Loki

iTrader: (1)

Any car will be fussy after shadetree surgery

The O2 sensor heater circuit needs to be fixed. That's probably causing the excessive time to enter closed loop too. Can't closed loop with a cold sensor.

The EVAP leak thing is also important, I don't think that's the air pump. Can you do me a favor and read the airflow g/sec and short term and long term fuel trim while idling warmed up? The trims should be zero and airflow around 5 g/sec at 800rpm. If they're not, you have an actual vacuum leak.

Since the issue affects only the front rotor, I'm still kinda suspecting injectors but we'll get to that. If that engine replacement is recent, it's possible the installer screwed up the injector connections. It's not uncommon.

Another hunch: the vacuum to the SSV and other intake solenoids comes from a vacuum reservoir. This has been known to crack creating a vacuum leak and other bad stuff. If the fuel trim data above points to vacuum leak, go over all the hoses and make sure they are connected correctly and nothing is cracked.

If you're methodical you'll find the problem. Just have to resist throwing parts at it.

Do we know the state of engine compression?

Power steering going out = check the connection below the overflow bottle. Clean and reseat if necessary.