Back from a long break!
12-19-23, 08:23 AM
#101
Full Member
Thread Starter
You have no return flow off the rail? Are you checking this while the car is running, or at the least you're jumpering the fuel pump with the wire or through holding the AFM flap open. This means that either the fuel pump isn't pumping enough pressure or the fuel pressure regulator has failed. Its unlikely clogged, but it's also a possibility.
Last edited by wopa20; 12-19-23 at 08:26 AM.
12-19-23, 08:29 AM
#102
Ill double check, i dont have a pressure tester at the moment but the supply line is really pressurized. line between rails too so that makes me think the banjo is allowing fuel across. but the line south of the pressure regulator is soft. I know its low pressure side.... If pressure is really high then pressure regulator relieves? If I add vacuum to pressure reg then it should relieve pressure?
12-22-23, 11:52 PM
#103
Full Member
Thread Starter
Tested fuel pressure (new pump)
also, new tps did absolutely nothing. Really need some help
correct me if I’m wrong…. I remember long time ago that when I turned my key on it “primed” the system, I would hear the pump turn on and then off when it reached pressure. This system does nothing with key on, only reaches “35psi when car is cranking
Last edited by wopa20; 12-23-23 at 10:47 AM.
12-23-23, 01:09 PM
#104
Tested fuel pressure (new pump)
also, new tps did absolutely nothing. Really need some help
correct me if I’m wrong…. I remember long time ago that when I turned my key on it “primed” the system, I would hear the pump turn on and then off when it reached pressure. This system does nothing with key on, only reaches “35psi when car is cranking
This is correct. It is a safety feature to prevent the pump from running in the event of a collision, adding fuel to the fire.
The fuel pump will run when cranking, and while the car is running. There is not "prime" on key-on.
12-23-23, 02:11 PM
#105
Rotary Freak
So just to sum-up the current situation before we continue diagnosing:
- With the MAF not plugged in, the car starts and idles but will die when the throttle is pressed
- When the MAF is plugged in, the car will not start or idle
- With the MAF not plugged in, the car starts and idles but will die when the throttle is pressed
- When the MAF is plugged in, the car will not start or idle
12-23-23, 04:07 PM
#106
Full Member
Thread Starter
I replaced fuel pump, tps, new sensor bottom of rad, removed antifreeze cold start stuff it didn’t work anyway. The only thing I didn’t looks into is the thermos alive on the intake( was worried about breaking it)
Last edited by wopa20; 12-23-23 at 04:17 PM.
12-23-23, 04:42 PM
#107
here's the thread you asked for:
https://www.rx7club.com/2nd-gen-gene...cking-1161196/
... though, at this point, i'm not sure it will be useful.
https://www.rx7club.com/2nd-gen-gene...cking-1161196/
... though, at this point, i'm not sure it will be useful.
12-23-23, 04:47 PM
#108
Rotary Freak
there was a time I could get the car running but now I can’t get it to run at all. I’ve tried combinations of in plugging changing tps etc
I replaced fuel pump, tps, new sensor bottom of rad, removed antifreeze cold start stuff it didn’t work anyway. The only thing I didn’t looks into is the thermos alive on the intake( was worried about breaking it)
I replaced fuel pump, tps, new sensor bottom of rad, removed antifreeze cold start stuff it didn’t work anyway. The only thing I didn’t looks into is the thermos alive on the intake( was worried about breaking it)
1. Plug the MAF back in. It's intriguing that it ran better without the MAF, but it won't help the car to run properly if you end up setting all the sensors around getting it to run without one.
2. Air is a given, since there's no way it isn't getting air unless the filter is clogged.
3. If you have a compression tester I would use it, but if not, do the quick and dirty comp test. Pull out the EGI fuses from the under-hood fuse panel and put them in the cupholder. Remove the upper plug wires and spark plugs, then have a friend crank the engine while you listen near the engine bay. You should hear the puffing noises come out evenly, psst-psst-psst-psst-psst. If you hear psst-...-...psst-...-... then an apex seal has given up. I don't think this is likely since your car was running before, but it's worth a try.
4. Spark can be checked by using a spark checker. Remember to put the EGI fuses back and reconnect the plug wires. If they're not sparking, and everything is plugged in (plug wires, coil packs) for sure, proceed to step 6.
5. Try to start the car one more time. Just in case.
6. Your injectors have been recently serviced so we know they're good, but we don't really know that they're firing. At least, not anymore since the car won't start now. The way to test that dovetails into the next steps. You have already tested fuel pressure so we know the pump is working (at least well enough to start).
7. Timing. I know you set your timing earlier, and the car will actually run even with the timing really far out, but it provides a convenient way to test the CAS and ECU. Put the engine at TDC by rotating the crank, then remove the CAS. Plug it back in to the harness and turn the key to IGN (but not start). When you rotate the CAS (I don't recall the direction, try both) you should hear a clicking noise coming from the injectors. The ECU is being tricked into thinking the engine is rotating and will try to fire the injectors at the correct time. You can also put a spark checker on the plug wires and watch while you rotate the CAS.
If you rotate the CAS and neither of the above happens (no click from injectors, no spark) then there is either an issue with the CAS, the wiring, or the ECU. If one of the above occurs but not the other, you've identified the problematic system and we can proceed from there. If both occur, then the next step is to re-time.
To retime it, I think I gave instructions before. But the long and short of it is to put the engine at the yellow mark on the pulley (first mark on the pulley as rotated clockwise if the colours are gone), rotate the gear on the bottom of the CAS so the divot lines up with the pointer cast into the body, and carefully insert it into the front cover while trying to keep it straight. It'll rotate a little, but it should still land such that the stud lines up with the adjustment slot in the CAS. You can try starting the car, but if it doesn't start then you can at least have a friend crank while you use the timing light to get it to fire at the yellow mark. This won't be perfect but should be more than good enough to start and idle.
If all the above works and then it still won't start, you can try testing if it's lean by using starting fluid. If the starting fluid helps, something is causing inadequate fuel. If it's the opposite problem (flooded) then you can try using some oil in the spark plug holes to build some comp before you start it again.
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diabolical1 (12-23-23)
12-23-23, 05:43 PM
#109
just saw your other thread ...
https://www.rx7club.com/general-rota.../#post12587589
if the state of the car right now is it's flooding out, and not starting, then either the timing is way, way off, or you're not getting spark/adequate spark.
are you getting any pops or low-pitched booms while cranking?
like WondrousBread said, go back to the basics ....
if you have a timing light, check where your timing is. if you don't have one, you should be able to rent one from AutoZone (though i'm sure if they are in Canada) or at least one of your local auto parts chain stores.
https://www.rx7club.com/general-rota.../#post12587589
if the state of the car right now is it's flooding out, and not starting, then either the timing is way, way off, or you're not getting spark/adequate spark.
are you getting any pops or low-pitched booms while cranking?
like WondrousBread said, go back to the basics ....
if you have a timing light, check where your timing is. if you don't have one, you should be able to rent one from AutoZone (though i'm sure if they are in Canada) or at least one of your local auto parts chain stores.
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wopa20 (12-26-23)
12-26-23, 08:45 AM
#113
Rotary Freak
They both look about right to me.
For leading, both plugs fire at the same time. So if you check the one plug, it's firing at (or near) the top tooth passing the reluctor and then also 90 degrees out. Both plugs should do the same thing.
For trailing, they're separate ignitors. So they fire at different times. One should fire a little past the tooth, the other should fire 90 degrees out from that.
(The CAS spins at 2x the speed of the crank, so 1/2 turn of the CAS is 1 turn of the crank, hence why the above numbers are 90 degrees out from one another when the rotors are actually 180° out). At least, I think so. Timing always confuses me.
The important thing is that we now know the CAS is working, and you have spark.
The last picture you uploaded looks about right, but there's no way to tell from above whether the CAS is installed 180 degrees out. So when you install it, there is a dimple on the bottom gear that needs to align with the pointer on the body of the CAS.
For leading, both plugs fire at the same time. So if you check the one plug, it's firing at (or near) the top tooth passing the reluctor and then also 90 degrees out. Both plugs should do the same thing.
For trailing, they're separate ignitors. So they fire at different times. One should fire a little past the tooth, the other should fire 90 degrees out from that.
(The CAS spins at 2x the speed of the crank, so 1/2 turn of the CAS is 1 turn of the crank, hence why the above numbers are 90 degrees out from one another when the rotors are actually 180° out). At least, I think so. Timing always confuses me.
The important thing is that we now know the CAS is working, and you have spark.
The last picture you uploaded looks about right, but there's no way to tell from above whether the CAS is installed 180 degrees out. So when you install it, there is a dimple on the bottom gear that needs to align with the pointer on the body of the CAS.
12-26-23, 08:49 AM
#114
Full Member
Thread Starter
Just my observation it appears the trailing has one one spark per rotation vs leading which has several
oh ok so if trailing are spectate I won’t see other spark
oh ok so if trailing are spectate I won’t see other spark
Last edited by wopa20; 12-26-23 at 08:53 AM.
12-26-23, 08:56 AM
#115
Rotary Freak
Yeah, that part is normal. Both leading plugs fire from the same igniter, so while there are two separate plugs they are treated as the same thing electrically by the ECU. It just sends one signal to fire both leading at the same time, so if you measured one plug you'll see two sparks per rotation of the engine (or 4x per rotation of CAS) the trailing does one (or 2x per rotation of CAS).
When one rotor is at TDC and needs the lead spark plug fired, the other is in its exhaust stroke. So the extra spark on the other wire doesn't cause any issues. This what they call a "wasted spark" system, because one spark is wasted.
One thing I do notice which might be odd is that when the leading does fire, it kind of does a double-blink from the spark checker. I'm not sure if that's normal (no longer have a stock ECU or CAS in my car). I've always used a digital spark checker with an LED, so I don't know if mine did that.
When one rotor is at TDC and needs the lead spark plug fired, the other is in its exhaust stroke. So the extra spark on the other wire doesn't cause any issues. This what they call a "wasted spark" system, because one spark is wasted.
One thing I do notice which might be odd is that when the leading does fire, it kind of does a double-blink from the spark checker. I'm not sure if that's normal (no longer have a stock ECU or CAS in my car). I've always used a digital spark checker with an LED, so I don't know if mine did that.
12-26-23, 09:13 AM
#116
Full Member
Thread Starter
One thing I do notice which might be odd is that when the leading does fire, it kind of does a double-blink from the spark checker. I'm not sure if that's normal (no longer have a stock ECU or CAS in my car). I've always used a digital spark checker with an LED, so I don't know if mine did that.[/QUOTE]
I noticed this too
I tried to start it, she’s trying much better than before but still stumbling
I noticed this too
I tried to start it, she’s trying much better than before but still stumbling
12-26-23, 09:22 AM
#120
Full Member
Thread Starter
12-26-23, 01:10 PM
#122
Rotary Freak
To set the TPS properly, the car has to be all the way warmed up. Otherwise the thermowax will bump the throttle open. You could use a hair dryer on the thermowax to simulate this, but you'll be there awhile. The car should still idle though, even if the TPS isn't exactly right. You could try leaving it unplugged and seeing what happens. If you can get it to idle and warm up, then you can set the timing and TPS properly from there.
I also seem to remember the voltage method being more reliable for me, but again, since I have a standalone ECU I haven't set it that way in a long time.
I also seem to remember the voltage method being more reliable for me, but again, since I have a standalone ECU I haven't set it that way in a long time.
12-26-23, 09:21 PM
#123
Full Member
Thread Starter
I remember reading something about being warmed up to set proper. I played around a bit and actually got to to for for a few seconds and dead again, back to not cooperating. I believe I flooded again…. There’s a puddle under car.
was thinking about double checking everything at the ecm??
or take intake apart again?
was thinking about double checking everything at the ecm??
or take intake apart again?
Last edited by wopa20; 12-26-23 at 09:23 PM.
12-26-23, 09:30 PM
#124
Rotary Freak
I remember reading something about being warmed up to set proper. I played around a bit and actually got to to for for a few seconds and dead again, back to not cooperating. I believe I flooded again…. There’s a puddle under car.
was thinking about double checking everything at the ecm??
or take intake apart again?
was thinking about double checking everything at the ecm??
or take intake apart again?