ProZac Posted July 22, 2015 Author Share Posted July 22, 2015 MAP sensor testing, values are absolute pressures. At ~66kPa -> 1.5V At ~100kPa -> 2.7V At ~200kPa -> 4.8V That's all within the factory specs from a series 6 FSM (which are surprisingly wide tolerances) Quote Link to comment Share on other sites More sharing options...
puddles Posted July 23, 2015 Share Posted July 23, 2015 Is it misfiring? Will it rev right up/make boost? How are you measuring the air/fuel mix, they are very smelly cars. it should idle smoothly with occasional burps with adjustment on the butterfly, with iat disconnected. faulty clutch switch will have hunting unstable idle whilst in gear. Quote Link to comment Share on other sites More sharing options...
puddles Posted July 23, 2015 Share Posted July 23, 2015 iac, not iat Quote Link to comment Share on other sites More sharing options...
Popular Post yoeddynz Posted July 23, 2015 Popular Post Share Posted July 23, 2015 12 Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 23, 2015 Author Share Posted July 23, 2015 Is it misfiring? Will it rev right up/make boost? How are you measuring the air/fuel mix, they are very smelly cars. it should idle smoothly with occasional burps with adjustment on the butterfly, with iat disconnected. faulty clutch switch will have hunting unstable idle whilst in gear. Currently it won't even start, fouled to hell plugs. Will try burning them off, or grab a new set if that isn't successful. No on the afr measuring, my wide band controller is currently loaned out. Will pop it in once I grab it back. Will have a look at clutch switch too, cheers. Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 23, 2015 Author Share Posted July 23, 2015 Both the Full and Narrow range outputs from the TPS sweep test fine. The manual doesn't give any specs, but the results were pretty logical. Quote Link to comment Share on other sites More sharing options...
Evan Posted July 23, 2015 Share Posted July 23, 2015 I can't remember what Brad did with this but is the ECU ok/not faulty? Quote Link to comment Share on other sites More sharing options...
Pelo. Posted July 23, 2015 Share Posted July 23, 2015 Nice work with the diagnosis effort, it's great to have those tools available. IIRC it's running a PowerFC? #CarStalker Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 23, 2015 Author Share Posted July 23, 2015 Nah, factory ECU. Apparently he'd had a couple of different ECU's in it for testing, with no success. Quote Link to comment Share on other sites More sharing options...
d.p.n.s Posted July 24, 2015 Share Posted July 24, 2015 Hay Zac Don't suppose it could be Leakey injectors ? And when you turn it on can you hear the fuel pumps prime the fuel rail and then shut off? Had a mate with an older model rx7 and the ecu wouldn't turn the fuel pump off after priming. And also remember reading an old oldschool post of an rx7 fouling the shit out of the plugs and i believe that was a combination of both Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 24, 2015 Author Share Posted July 24, 2015 The injectors have been tested, and they are apparently find. If there was a mechanical seal issue though, that could certainly account for what's happening. If I don't get it sorted by checking sensors and things around the outside of the engine, I'll dig in that deep and have a look . Yeah, can hear the pump prime, and then shut off. I don't think there is any fuel pressure feedback to the ECU's on these cars, so it would just be on a timer. Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 25, 2015 Author Share Posted July 25, 2015 Found half an hour tonight to have a little play. Set the TPS as correctly as I could with the engine cold, and the error code for that has disappeared. Took the plugs out and they were super wet and gassy, as expected. Gave them a squirt with brakeleen, dried them out, then hit them with a MAP torch to burn the rest of any junk out of em. Hopefully that will bring them back to life. I bought a new set too, but If I can troubleshoot with an old set it'll save me money, as they be expensive! Quote Link to comment Share on other sites More sharing options...
piazzanoob Posted July 25, 2015 Share Posted July 25, 2015 I know that the injectors have already been tested but I've had a case at work were it wasn't untill they were had been tested on the 4th go that they actually found a fault with them. Sometimes a second test will find things that hadn't been found before. Quote Link to comment Share on other sites More sharing options...
Abarth Posted July 25, 2015 Share Posted July 25, 2015 I remember a thread on here with an FD which had the air temp and water temp sensors plugged in the wrong way after being rebuilt as they both had the same plugs. ECU was adding extra fuel as it was constantly seeing air temp readings instead of water temps. Apparently these have two water temp sensors too, one for the gauge and one for the gauge. Wicked car too btw!! Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 25, 2015 Author Share Posted July 25, 2015 Loving all the info guys, all these things are getting added to the list of things I'll work through as I find time. Cheers! Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 25, 2015 Author Share Posted July 25, 2015 It showed some signs of life this morning with the plugs cleaned. Didn't actually start, but was very very close. I was scoping the injector signal again, and I could see the pulse width decrease to a much more reasonable 5ms when it was almost running. This makes a lot of sense, and plays into the known problem this generation of rotaries have with rich hot-starts. Got a cleaner image of the injector closing on the scope too, and it looks like you'd expect: Still waiting for pressure sensors to turn up from China to check fuel pressure and compression. When my wife has some time later on I'll get her to turn the ignition for me while I scope out the spark with a timing light. Will have to clean the plugs again I suppose. They're pretty fucked by this stage, but I just don't want to throw a new set at it until I've found the problem(s). My gut feeling currently is that its a mechanical seal issue in the fuel system. A fuel pressure reading will reveal some good info here, as if the pressure drops quickly to zero once the fuel pump is no longer running, that's a pretty good indication of a leak somewhere. If this is the case, as there isn't any fuel spraying around the engine bay, or one the floor of the garage, I would think it pretty much has to be leaking internally. There go those assumptions again... . Quote Link to comment Share on other sites More sharing options...
Dell'orto Posted July 25, 2015 Share Posted July 25, 2015 I remember a thread on here with an FD which had the air temp and water temp sensors plugged in the wrong way after being rebuilt as they both had the same plugs. ECU was adding extra fuel as it was constantly seeing air temp readings instead of water temps. Apparently these have two water temp sensors too, one for the gauge and one for the gauge. Wicked car too btw!! Was this car haha 2 Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 26, 2015 Share Posted July 26, 2015 hasn't got a dodgy one of those sensors then? if it hasn't actually fixed the problem but made it better? Quote Link to comment Share on other sites More sharing options...
Dell'orto Posted July 26, 2015 Share Posted July 26, 2015 No, I specifically didn't replace any sensors so I could lose lots of money 5 Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 26, 2015 Share Posted July 26, 2015 shit dude, just asking the questions. do you know how many times an issue is something really small. ive never actually had a car break down due to a major failure, its always been something little like that. that really fucked me off, but im trying really hard to withhold snarky comments. Quote Link to comment Share on other sites More sharing options...
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