Getting my TII Running
02-20-10, 06:04 AM
#51
someone else on another forum questioned the compression (even though I'm pretty sure the engine is good). They advised:
try taking the plugs out and putting a little oil in the holes(on the leading plugs only) and if it starts up (and will blow a **** load of smoke) it has not enough comp.
my old rx7 before I got the motor rebuilt would not start if I parked it for more than a day,bit of oil in there and off she would go in massive cloud of smoke.
my old rx7 before I got the motor rebuilt would not start if I parked it for more than a day,bit of oil in there and off she would go in massive cloud of smoke.
02-21-10, 03:07 AM
#52
Went to the car for a few minutes with my brand spanking new multimeter today. Injectors checked out ok regarding resistance (they were all around 15Ω (should be 12-16Ω). Fuel pump resistor relay had some readings a little out of spec:
A-B: 0.6Ω (should be 0Ω)
C-D: 82Ω (should be 60-92Ω)
E-F: 1.2Ω (should be 0.7-0.94Ω)
That's not too much out of spec, but could that cause the car not to start?
The search continues...
A-B: 0.6Ω (should be 0Ω)
C-D: 82Ω (should be 60-92Ω)
E-F: 1.2Ω (should be 0.7-0.94Ω)
That's not too much out of spec, but could that cause the car not to start?
The search continues...
03-07-10, 04:05 AM
#53
Did some more testing on the car today, although not the injector testing I was originally hoping for. Instead I was playing around with the multimeter a little.
Crank angle sensor resistances - all within spec.
Circuit Opening Relay resistances - all within spec.
But the bizarre one is the circuit opening relay voltages. Connected the battery again, put the ignition to start and tried to read a voltage from all terminals on the relay, but none of them were giving me any volts whatsoever. Tried again and tried a different grounding point (this time a socket from the radio harness as I know that's good, and same thing. Turned the key to start and the interior light just went out, as well as the door lights. Removing and replacing the key didn't make them come back on but disconnecting the battery and then reconnecting brought the lights back on.
So what would cause all the voltages to be registering as 0V? If everything was hooked up it would crank before when the key was turned, but at the moment the plugs are out, as well as some injector wiring. Just seems strange...
Crank angle sensor resistances - all within spec.
Circuit Opening Relay resistances - all within spec.
But the bizarre one is the circuit opening relay voltages. Connected the battery again, put the ignition to start and tried to read a voltage from all terminals on the relay, but none of them were giving me any volts whatsoever. Tried again and tried a different grounding point (this time a socket from the radio harness as I know that's good, and same thing. Turned the key to start and the interior light just went out, as well as the door lights. Removing and replacing the key didn't make them come back on but disconnecting the battery and then reconnecting brought the lights back on.
So what would cause all the voltages to be registering as 0V? If everything was hooked up it would crank before when the key was turned, but at the moment the plugs are out, as well as some injector wiring. Just seems strange...
03-14-10, 07:30 AM
#55
Bit of an update here, and this time with a tiny possibility of a breakthrough. First of all, I checked the circuit opening relay voltages and they all checked out pretty much ok. Under cranking the voltages that should be 12V dipped to about 9.7-10V but that is understandable as the starter drains some of the power.
Got a fuel pressure gauge and hooked it up between the fuel filter and rail to check my pressures. Both under cranking and when priming the fuel pump using the check connector I was getting no pressure reading on the gauge.
Went to the fuel pump and tested the voltage on the pump connector when cranking. Was getting a reading of only 5V. Way below the 12V it should be. So I'm thinking a possible fuel pump rewire may be on the cards and that might be the reason no pressure was building up.
But then I decided to check the fuel pump was pumping out fuel when a full 12V was applied. Hard wired it up to the battery to test and was still getting no pressure reading at the gauge. Removed the gauge and had the hose just running from the fuel filter to the floor. When the pump was running there was some fuel coming out, but it was like a half-on tap (if that makes any sense). Pulled the main hose off the pump and just tested it with the pump following to atmosphere. Got the same steady but not really spectacular fuel flow.
So it looks like there are at least 2 issues:
a. Only 5V getting to the fuel pump
b. The fuel pump not pumping much fuel even when a definite 12V is applied
Am gonna do more testing this week and will also try to read some diagnostic info from the ECU to see if anything is being detected as a problem.
Got a fuel pressure gauge and hooked it up between the fuel filter and rail to check my pressures. Both under cranking and when priming the fuel pump using the check connector I was getting no pressure reading on the gauge.
Went to the fuel pump and tested the voltage on the pump connector when cranking. Was getting a reading of only 5V. Way below the 12V it should be. So I'm thinking a possible fuel pump rewire may be on the cards and that might be the reason no pressure was building up.
But then I decided to check the fuel pump was pumping out fuel when a full 12V was applied. Hard wired it up to the battery to test and was still getting no pressure reading at the gauge. Removed the gauge and had the hose just running from the fuel filter to the floor. When the pump was running there was some fuel coming out, but it was like a half-on tap (if that makes any sense). Pulled the main hose off the pump and just tested it with the pump following to atmosphere. Got the same steady but not really spectacular fuel flow.
So it looks like there are at least 2 issues:
a. Only 5V getting to the fuel pump
b. The fuel pump not pumping much fuel even when a definite 12V is applied
Am gonna do more testing this week and will also try to read some diagnostic info from the ECU to see if anything is being detected as a problem.
03-25-10, 08:42 AM
#60
Breakthrough! Borrowed a known working Walbro fuel pump and assembly last night and dropped it into the fuel tank. Connected the fuel pump test wire and turned the ignition on. Had more pressure than I know what to do with! So I am almost certain I've found my problem, and now I just need to check if it's the pump or the pump assembly that is causing no pressure to be sent into the system.
And once a little ECU issue is sorted out (at least I hope it's little), the car can get put back together and can be fired up. Of course, it sounds so simple in theory! And I've got to probably get an adjustable FPR somehow into the system as I've rewired the fuel pump - might be a little messy as the stock FPR is pressed into the fuel rail. But I can cross/jump off that bridge when I come to it.
And once a little ECU issue is sorted out (at least I hope it's little), the car can get put back together and can be fired up. Of course, it sounds so simple in theory! And I've got to probably get an adjustable FPR somehow into the system as I've rewired the fuel pump - might be a little messy as the stock FPR is pressed into the fuel rail. But I can cross/jump off that bridge when I come to it.
03-25-10, 06:23 PM
#62
Thanks. Haven't ordered the "whine-bro" as I just borrowed one for testing purposes, and I still need to check if it was the pump or assembly itself that was at fault. Will probably opt for an FD pump though as the fuel pump rewire is already going to give me a little higher pressure.
03-26-10, 10:32 AM
#63
One step forward, two steps back...
Was doing some more testing this evening to try and fid out if it was the pump or the assembly at fault. Anyway, I got back to the combination of the old fuel pump and old assembly and turned ignition on and I got fuel pressure. It was pretty much where it should be when I had the gauge T'd to it and the hose then going to the fuel rails. The strange thing there was that as soon as I turned the key off the pressure just dropped off straight away.
I then tried just plugging the gauge into the fuel filter and testing pressure that way. I got a maximum pressure of just below 70psi and after about 90 seconds it had already dropped to about 50psi. Tomorrow I'll plug the Walbro back in and see what figures that gives me for the same tests.
Feeling like I'm going in circles a bit here now.
Was doing some more testing this evening to try and fid out if it was the pump or the assembly at fault. Anyway, I got back to the combination of the old fuel pump and old assembly and turned ignition on and I got fuel pressure. It was pretty much where it should be when I had the gauge T'd to it and the hose then going to the fuel rails. The strange thing there was that as soon as I turned the key off the pressure just dropped off straight away.
I then tried just plugging the gauge into the fuel filter and testing pressure that way. I got a maximum pressure of just below 70psi and after about 90 seconds it had already dropped to about 50psi. Tomorrow I'll plug the Walbro back in and see what figures that gives me for the same tests.
Feeling like I'm going in circles a bit here now.
04-07-10, 07:43 AM
#64
IT LIVES!!!
Well I don't want to get too ahead of myself, but it started up tonight and was idling on its own and not wanting to die (which it's been doing before). Idle was fluctuating between 1,000 and 1,500rpm but that might be down to the TPS not being adjusted right (or a huge number of other things).
Most recent changes I did this evening were to throw a different set of injectors in there, as well as cap off a few vacuum lines and reroute a couple more as my side job of simplifying the engine bay a little. I also eliminated the BAC valve. I know it's not the first step most of you would take when troubleshooting an idle problem but I was willing to try something a little different. Not sure which one did it but I'll send off my own injectors to get cleaned and flow tested by Witch Hunter and see what the report says when they come back. I messed with the TPS adjustment before but the engine was cold and I've still got the thermowax and secondary butterflies in there so it's probably all askew now. Once that's fixed it might, touch wood, run right.
Once it's idling OK I'll consider taking it onto the road but have got to lift the front end an inch or so so that it'll actually get out of my apartment parking area and not get beached on the kerb like some red Wankel whale.
Well I don't want to get too ahead of myself, but it started up tonight and was idling on its own and not wanting to die (which it's been doing before). Idle was fluctuating between 1,000 and 1,500rpm but that might be down to the TPS not being adjusted right (or a huge number of other things).
Most recent changes I did this evening were to throw a different set of injectors in there, as well as cap off a few vacuum lines and reroute a couple more as my side job of simplifying the engine bay a little. I also eliminated the BAC valve. I know it's not the first step most of you would take when troubleshooting an idle problem but I was willing to try something a little different. Not sure which one did it but I'll send off my own injectors to get cleaned and flow tested by Witch Hunter and see what the report says when they come back. I messed with the TPS adjustment before but the engine was cold and I've still got the thermowax and secondary butterflies in there so it's probably all askew now. Once that's fixed it might, touch wood, run right.
Once it's idling OK I'll consider taking it onto the road but have got to lift the front end an inch or so so that it'll actually get out of my apartment parking area and not get beached on the kerb like some red Wankel whale.
04-07-10, 11:19 PM
#67
You might just be the only FC owner to remove their BAC while KEEPING the thermowax and butterflies 
but congrats on getting it to "idle" (technically you can't set timing or make any other adjustments with it that high...) One step closer to enjoying the car properly!
but congrats on getting it to "idle" (technically you can't set timing or make any other adjustments with it that high...) One step closer to enjoying the car properly!
04-08-10, 12:23 AM
#68
You might just be the only FC owner to remove their BAC while KEEPING the thermowax and butterflies but congrats on getting it to "idle" (technically you can't set timing or make any other adjustments with it that high...) One step closer to enjoying the car properly!
but congrats on getting it to "idle" (technically you can't set timing or make any other adjustments with it that high...) One step closer to enjoying the car properly!I can't set timing although it really shouldn't need to be set as nothing has been done with that spect of the engine since it was running relatively well. Will still check it when I can but that's only going to take place once I get the car moving.
04-10-10, 07:48 AM
#69
Tiny tiny steps, but it's getting there very slowly. Fired the engine up again today and decided to disconnect the TPS while it was fluctuating to see what happened. The fluctuating stopped and it was holding idle but with a slight misfire. So it looked like the TPS or related crap around there was out of sync.
I managed to stop the fluctuating by screwing the fast idle adjustment screw all the way in. I know it shouldn't be like that but I've been following NJGreenBudd's thread (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/video-still-crappy-idle-no-response-idle-adjustment-657023/) a little and not it was something that was initially said to him. With that, I also adjusted the TPS sensor so it was giving me exactly 1VDC.
Starting the car I am getting an idle of about 1,100rpm and running pretty smooth. If I give it some gas the idle will come down again but only to around 1,300 or 1,400rpm and will then have a bit of a misfire. Think that might be to do with things still being out of spec. I'm going to try simplifying the whole shebang and take the thermowax/cold start system out of the equation. Might also get the PVC pipe setup instead of the intercooler to help with troubleshooting.
Any other thoughts on how I could bring the idling down? I'll also try to measure the opening of the throttle plate too to make sure it's within FSM spec.
I managed to stop the fluctuating by screwing the fast idle adjustment screw all the way in. I know it shouldn't be like that but I've been following NJGreenBudd's thread (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/video-still-crappy-idle-no-response-idle-adjustment-657023/) a little and not it was something that was initially said to him. With that, I also adjusted the TPS sensor so it was giving me exactly 1VDC.
Starting the car I am getting an idle of about 1,100rpm and running pretty smooth. If I give it some gas the idle will come down again but only to around 1,300 or 1,400rpm and will then have a bit of a misfire. Think that might be to do with things still being out of spec. I'm going to try simplifying the whole shebang and take the thermowax/cold start system out of the equation. Might also get the PVC pipe setup instead of the intercooler to help with troubleshooting.
Any other thoughts on how I could bring the idling down? I'll also try to measure the opening of the throttle plate too to make sure it's within FSM spec.
04-20-10, 10:07 AM
#70
"Tantalisingly close" is the best way to describe the FC at the moment. Did the "throttle body mod" and pulled a bunch of unnecessary stuff off the throttle body, but have found that setting the idle and TPS is an artform which I can't master at the moment. Might be partly due to the fact that I've bent a throttle lever after thinking it shouldn't have been bent one way in the first place. The effect should be minimal but I might have to get a new set of levers for it from Mazda
I've got to the situation where the car will idle at about 1000rpm when I fire the engine up, but then after 10 seconds or so it'll rise to around 1400rpm and after a little while will start to fluctuate between 1000 and 1400rpm.Just have to find out how to fix that. Tried setting the TPS through standard resistance or voltage to 1vdc, but it didn't sort things out completely
It was all warmed up again today and is just a bit of playing around away from working I think.
I've got to the situation where the car will idle at about 1000rpm when I fire the engine up, but then after 10 seconds or so it'll rise to around 1400rpm and after a little while will start to fluctuate between 1000 and 1400rpm.Just have to find out how to fix that. Tried setting the TPS through standard resistance or voltage to 1vdc, but it didn't sort things out completely
It was all warmed up again today and is just a bit of playing around away from working I think.
05-06-10, 12:30 AM
#71
Well I just can't figure this damn idle out. With the TPS disconnected the idle is steady but a little rough. With the TPS connected it goes between 1500 and 1000rpm eveery second or 2. These are the things I've tried:
Setting TPS through voltage (1vdc) and resistance
Checking vacuum lines and hoses for leaks, and rerouting/replacing some
Tried 2 different TPS sensors
Tried 3 different boost pressure sensors
And nothing seems to sort it out. At the moment, the idle revs are as low as they can be (set through the idle stop screw on the back of the throttle body. If I screw that screw in, the idle will increase but the fluctuations remain. Once the car is under load it seems like that fluctuation disappears. I say "seems" as I haven't yet got the car out of my parking area.
Am thinking I might take it for a drive at night and just see if it needs a drive or something for the cobwebs to blow away and things to get back into order. Any other ideas on what I can do though?
Setting TPS through voltage (1vdc) and resistance
Checking vacuum lines and hoses for leaks, and rerouting/replacing some
Tried 2 different TPS sensors
Tried 3 different boost pressure sensors
And nothing seems to sort it out. At the moment, the idle revs are as low as they can be (set through the idle stop screw on the back of the throttle body. If I screw that screw in, the idle will increase but the fluctuations remain. Once the car is under load it seems like that fluctuation disappears. I say "seems" as I haven't yet got the car out of my parking area.
Am thinking I might take it for a drive at night and just see if it needs a drive or something for the cobwebs to blow away and things to get back into order. Any other ideas on what I can do though?
05-09-10, 07:25 AM
#72
Doesn't sound like much but it was a pretty big step taken today. Had the FC actually out of my apartment and in the dizzy heights of 2nd gear going down the road. Only went about 100m or so and then turned around and came back (mainly as I'm driving with no plates or anything and didn't want police to turn the corner and see me), but it was great to see the car actually being able to move. Something it's not done for quite a few months anyway.
The idle is still up and down like a Maehara girl's T-back, and I think the front of the car might actually be pointing slightly skyward compared to the rear (raised the coilovers so it would clear the kerb ramp coming out of my parking area but did it too much; may need to come back down half an inch or so). It's hardly as if I'm drag racing in the thing just yet, but it is getting there. I just need this damn idle sorting. Might get a real long screwdriver and play with it while the engine's on to see if I can calm it down. But even if I can get it to calm down it still needs to come down below 1,000rpm so it will not play around with timing at idle.
The idle is still up and down like a Maehara girl's T-back, and I think the front of the car might actually be pointing slightly skyward compared to the rear (raised the coilovers so it would clear the kerb ramp coming out of my parking area but did it too much; may need to come back down half an inch or so). It's hardly as if I'm drag racing in the thing just yet, but it is getting there. I just need this damn idle sorting. Might get a real long screwdriver and play with it while the engine's on to see if I can calm it down. But even if I can get it to calm down it still needs to come down below 1,000rpm so it will not play around with timing at idle.
05-17-10, 07:32 AM
#73
I'm a boost leak away from this damn thing running. Used an air tank and a boost leak checker contraption tonight. Hooked it up to my turbo and pressurized it to about 0.6bar. Thing lost pressure within a couple of seconds with an audible noise. Then hooked it straight up to the intake manifold and did the same. Got the same result with the noise coming from somewhere on the driver's side of the intake manifold area. Tried spraying soapy water over it all but couldn't see any bubbles.
That's got to be what's causing my strange idle though. Have just got to find out where the leak's coming from...
That's got to be what's causing my strange idle though. Have just got to find out where the leak's coming from...
05-31-10, 09:09 AM
#75
The 6 16+ hour working days I've just pulled must have pleased the rotary gods, as tonight after a bit of playing around I started up the FC and had it idling perfectly, at 800rpm. No sign of a hiccup, misfire or surge.
Took the throttle body apart again in my ongoing search for a solution to the surging idle, and I found that 2 of the lower throttle plates were fractionally open at idle. Posted a couple of pics up here and also had it pointed out to me that when I'd removed the cold start system I hadn't yet removed a cold start cam that I needed to (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/did-i-do-my-aws-removal-right-906231/). Closed the throttle plates, cleaned it up as best I could and pulled the cam off. Refitted it and fired it up. Have never been so relieved to hear a car idling!
Fingers crossed it'll still do it in the morning. Just need to bleed the clutch system so I can actually drive it down the street again and test it, but then it will be ready for shakken (Japanese MOT), registering and some fun
Took the throttle body apart again in my ongoing search for a solution to the surging idle, and I found that 2 of the lower throttle plates were fractionally open at idle. Posted a couple of pics up here and also had it pointed out to me that when I'd removed the cold start system I hadn't yet removed a cold start cam that I needed to (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/did-i-do-my-aws-removal-right-906231/). Closed the throttle plates, cleaned it up as best I could and pulled the cam off. Refitted it and fired it up. Have never been so relieved to hear a car idling!
Fingers crossed it'll still do it in the morning. Just need to bleed the clutch system so I can actually drive it down the street again and test it, but then it will be ready for shakken (Japanese MOT), registering and some fun