Running rich as #@*&
- Thread starter ca91mkIII
- Start date
In this particular case the WB shouldn't even be in the equation. After all if he brought the car to a shop they wouldn't be using it and rightly so. It's not at all needed.
3p: I forgot about your question from earlier. The only code that was stored was code 51 and that's the reason the throttle body came off was so that I could recalibrate the tps because it did need it.
Just so the information is out there, I did free air calibrate the wideband per innovate's instructions.
Just so the information is out there, I did free air calibrate the wideband per innovate's instructions.
I should have been more clear. My mistake. I have two codes stored now. Coolant temp sensor and intake air temp sensor which is codes 22 and 24 but I unplugged both components while the vehicle was running so I know why those two are stored. I haven't really driven the car since I did that so that is why both codes are still in there.
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Well 400-700 Hz at cold idle seems high, but that does not necessarily mean the AFM is bad since we have no idea how your engine is running. You need to test a known stable condition like hot idle.
Also, you have not answered a critical question. Are you getting a code 34 at 3500 rpm per your first post.
Also, you have not answered a critical question. Are you getting a code 34 at 3500 rpm per your first post.
I don't know why I am having a hard time answering the question. I am not getting code 34 at all but I do hit fuel cut around 3500 rpm. I know people mention that they see the cel flash and I never see any of that. The engine is basically building power and the rpms get to the almighty ~3500 rpm and then the whole car shakes violently and falls on its face. I will check the frequency of the afm again at hot idle tomorrow when it is hopefully a little warmer outside. Playing with a motor in roughly twenty degree weather sucks.
12 volt mod? If not could be a bad fuel pump relay, something not unheard of in these cars. I've seen it twice. Then again you ought to be focusing on the mixture problem first.
Riyad: That is actually the exact reason I thought I had fuel cut hitting because it sounds just like fuel cut. I have tested the AFM at normal operating temp and I am seeing about
16 kHz at idle on the KS terminal and then 27 mV between terminals Vf and E1. So based on those numbers, I am replacing the AFM and seeing what I get from there. Hopefully that is the only issue but I will just have to wait and see.
jetjock: Since you brought it up... what is the 12 volt mod? I have seen a few pictures of an extra ground strap on the ignitor. Is that what you are referring to or is that something completely different?
16 kHz at idle on the KS terminal and then 27 mV between terminals Vf and E1. So based on those numbers, I am replacing the AFM and seeing what I get from there. Hopefully that is the only issue but I will just have to wait and see.
jetjock: Since you brought it up... what is the 12 volt mod? I have seen a few pictures of an extra ground strap on the ignitor. Is that what you are referring to or is that something completely different?
Yes... the 12 volt mod (if I understand it correctly) is simply shorting the terminals on the passenger side of the engine bay so that it runs 12volt full time. (well.. its a bit more complex than that.. but that's kinda what I think in my head). I didn't do that with mine (running Denso MKIV fuel pump) and didn't have enough info to say that I actually needed to. I thought it was a safety feature to prevent fuel pump overheating at idle on stock. (now I will wait for jetjock to correct or confirm.. 
)
Here's the link to the "how-to"
http://www.supramania.com/forums/sh...all-with-12VRelay-all-in-one-thread-with-Pics
Good info/pics here
http://www.supramania.com/forums/showthread.php?9417-Fuel-pump-rewire-using-a-relay
This was my first link to the 12v mod that didn't sell me on actually doing it. I may do it later on because Im running 1000 cc injectors now...
http://www.supramania.com/forums/showthread.php?144833-Walbro-fuel-pump-upgrade-is-12V-mod-required
)Here's the link to the "how-to"
http://www.supramania.com/forums/sh...all-with-12VRelay-all-in-one-thread-with-Pics
Good info/pics here
http://www.supramania.com/forums/showthread.php?9417-Fuel-pump-rewire-using-a-relay
This was my first link to the 12v mod that didn't sell me on actually doing it. I may do it later on because Im running 1000 cc injectors now...
http://www.supramania.com/forums/showthread.php?144833-Walbro-fuel-pump-upgrade-is-12V-mod-required
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Based on your posts replacing the AFM is a bad move. As for the 12 volt thing, if you had it you'd know what it is. Try running the engine with +B and FP jumped. If the stumble goes away the pump relay is suspect.
Why would replacing the AFM not help at all in this situation? I am up for correction if my logic is incorrect, but the computer is seeing 16,000 Hz coming from the AFM, when it should be no more then ~160 Hz, while the TPS is reading no more then 5% open, coolant at normal operating temps, and RPM at idle speed.
I didn't know what the mod was called specifically, but I have run the vehicle with an inline fuse and toggle switch wired directly to the battery and fuel pump with the same problem. Currently I am running the fuel pump with the toggle switch still, but power pickup is now at the ignition hot terminal on the fuel pump relay wiring but no relay is involved. I would have mentioned this before, but I didn't think it could cause this problem to be honest.
Could over retarded timing cause some of this issue? Just thinking out loud here, but too far retarded timing could cause loads of unburned fuel to be pushed out of the cylinder giving the afr a false rich signal, the spark plugs to be clean as the spark would be too late in the combustion cycle and mostly used as burning off fuel that stuck to the plugs, and the cut out at high RPMs because the spark is too far behind the combustion cycle and the engine literally tries to diesel with too low of compression. Of course the only thing it doesn't explain is the weird signal I am reading from the AFM, but the other symptoms seem to fit or at least they do in my thinking out loud. I checked timing once before and it was fairly close to what the TSRM called for, but I hadn't taken into account for the longer duration and larger lift of the cams. Maybe? Its an easy thing to check for sure.
I didn't know what the mod was called specifically, but I have run the vehicle with an inline fuse and toggle switch wired directly to the battery and fuel pump with the same problem. Currently I am running the fuel pump with the toggle switch still, but power pickup is now at the ignition hot terminal on the fuel pump relay wiring but no relay is involved. I would have mentioned this before, but I didn't think it could cause this problem to be honest.
Could over retarded timing cause some of this issue? Just thinking out loud here, but too far retarded timing could cause loads of unburned fuel to be pushed out of the cylinder giving the afr a false rich signal, the spark plugs to be clean as the spark would be too late in the combustion cycle and mostly used as burning off fuel that stuck to the plugs, and the cut out at high RPMs because the spark is too far behind the combustion cycle and the engine literally tries to diesel with too low of compression. Of course the only thing it doesn't explain is the weird signal I am reading from the AFM, but the other symptoms seem to fit or at least they do in my thinking out loud. I checked timing once before and it was fairly close to what the TSRM called for, but I hadn't taken into account for the longer duration and larger lift of the cams. Maybe? Its an easy thing to check for sure.
ca91mkIII;1983351 said:
Then go ahead and replace it. Let us know what happens. As for your thinking out loud, there's too much anal-lyzing in it. Forest for the trees. And the O2 sensor doesn't measure fuel. It measures O2...
I have a major update!!!! I ended up replacing the mass air flow sensor and a coil and the car no longer falls on its face. It boosts up to 8 psi and holds strong through every single gear now. All I can say is WOW!! What a huge difference. It still runs on the rich side, but its a work in progress. I can at least open the engine up and run it hard.