new to me, 98 M3
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24.1 lb/sec is an absurd value which equates to 14,500 HP
24.1 lb/min is a very realistic value which equates to 240 HP
You should be seeing 0.35-0.40 lb/sec at WOT for that rpm.
rpm dip upon return to idle means the engine isn't idling efficiently. Most of the time this means a vacuum leak. Sometimes it means check your idle control valve, clean it and inspect the plumbing on it and make sure it works.
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Yeah, my car is really fast!
sorry meant .24 I'll take a passenger with me who can watch more closely to see if it gets up towards .35I'll keep searching for vac leaks. Going to have get it up on ramps. Because of the SC the ICV is located under the SC and very hard to get at. I was hoping in the back of my mind i wouldn't have to deal with that, but am realizing I'm probably going to need to inspect it. Not sure how i'm going to get at it. ugh......
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Ok, finally got some time to pull a bunch of numbers from my car. It was not fully warmed up, but idling around 750rpm.
Absolute throttle position: 18.8%
Voltage: 14.00
B1S1 O2 voltage: 0.125 (bounced between this and 0.950, probably an issue with my reader)
B1S2 O2 voltage: 0.960
B2S1 O2 voltage: 0.115 (bounced between this and 0.950, probably an issue with my reader)
B2S2 O2 voltage: 0.940
Short term fuel trim 1: Between -2.4 and 0.8
Long term fuel trim 1: 2.34
Short term fuel trim 2: Between -.8 and 2.4
Long term fuel trim 2: 1.56
Timing advance: between 15 and 17.5
Mass airflow 1 (g/s): Between 3.57 and 3.85
Mass airflow 2 (g/s): Between 3.43 and 4.9 (4.9 was just after startup, rpm's not fully settled)
Hopefully this helps!
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Thanks M42B32. I've discovered I have the 803 Porsche MAF because of the supercharger and upgraded injectors. So, not sure my numbers will give much of a comparison. I'd say the MAF appears to be functioning though. That would have also been new at the time of SC install.
I haven't had a chance to drive much since this weekend. Summer tires on the M and snow don't mix. Hopefully tomorrow I'll be able to get it out of the subdivision. Spent the weekend tearing down to the ICV. Cleaned that real well, it was pretty dirty. Put everything back together real tight, added hose clamps to vacuum lines that didn't have any just to be safe. Not hearing any leaks. Cleaned the air filter. It was filthy. Still getting crap out of it after using the K&N cleaner three times. Cleared codes and only took for a couple short trips. Pending codes didn't come back. Not holding my breath though, codes seemed to appear when I'd get to highway speeds, which I didn't do yet. Tomorrow should be a good test.
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Does your chip tune account fort the different MAF?/did this MAF and chip tune come from the vendor that sells the SC kit?
according to the website yes
http://www.eurosporthighperformance.com/supercharger.html
also, car was running fine with no CEL for about 500 miles when I got it, so hopefully tune is good. TRM Tuning in Cummings, GA did the install work. Apparently they're reputable and they did respond to me that they worked on this car, so i know that's true. Keeping fingers crossed it was a vacuum leaked.
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ok, code still there. Update on some numbers I noticed while driving today.
Seems my short term fuel trim 1 is out of wack. It stays around -18-20% while in gears 1-3 when going upto 4-5th gears at highway speeds it drops to -10.6-12% which still seems like a high number compared to SHRTFT2 which stays in the -3-6% range. Long term still holds steady at -8.6% for both.
Thoughts if that might still point to a vacuum leak or fuel delivery issue?
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Maybe the coolant pump or lines?
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Your STFT is an instant reading of fuel being used and should remain similar across both banks. If you have one bank out of wack then that bank may have an issue. Running that far negative would point towards an over fueling issue and the ecu is trying to pull fuel away but you want to evaluate the numbers at idle and at 2500 rpm. Leaky injector, bad maf, bad 02, those are a few items that could cause this.
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Morning all, no fun updates, rims will go on next week so I'll get pics up when that's done!
Still working on this dang CEL. No vacuum leaks, changed fuel filter as well. I rented a fuel pressure test gauge from Orileys to make sure I'm not getting low pressure. Here's what happened. T'd it into the fuel line at the fuel pump in the back seat. Turned pump on and no reading on the gauge. Perhaps fuel isn't going through? So, I start the car and car starts right up and runs, but still no reading on the gauge. OK, well maybe it's just a bad gauge. So, we return that one and get a second one from Autozone. Hook that one up, same thing. No pressure on gauge but pump is clearly working and fuel it flowing through the "T" connection because car runs fine. We could be idiots and hooked it up wrong, but I don't really see how that would be possible, you just put the "T" fitting inline and connect the gauge. Two gauges wouldn't both be bad you wouldn't think.
So, maybe this means something, I'm not getting enough back pressure to register on the gauge? Fuel pressure regulator? If that is shot wouldn't I be running rich? I thought having the negative short term fuel % mean that I was running lean. Or does that reading mean I'm actually running rich and the computer is trying to Lean out the fuel? That might make sense then if the FPR is shot.
Thanks again for all the help, Andrew
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ok I'll try that today. Only 1 line coming out of my fuel pump. The return lines are in a separate spot on my car (rear driver side of the tank)
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yep, i for sure had the pump, i pulled it to inspect it as well to make sure the filter wasnt dirty.
I just pulled the vacuum line on the FPR and it was dry. Is there any way to check for leaking injectors? I think I'm down to that as being the only thing I haven't checked. Other thing I could think of would be my CCV but that seems OK. when I googled symptoms of that being bad they said open the oil fill on the valve cover and your car would start sounding like Chewbacca. Mine checked out fine for that.
ugh...refuse to take it to a shop
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My only experience with leaking injectors is when the car has a hard-start condition after sitting overnight. The problem injectors revealed themselves by pulling the plugs and watching one or two jets of fuel spray out of one or more cylinders while cranking (the fuel that pooled up being pushed out)
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hmm, yeah i don't have that symptom.
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At idle with my foot off the gas my '99 M3 sits at 17%/18% throttle. Not sure on the rest of the numbers though. When I get back from my trip I can see what my car reads for the rest of the parameters you posted to compare
Company that made the Eurosport SC isn't around anymore. TRM tuning in GA installed it, not sure if they do actual programming to customize the tune or if Eurosport gave them the tune.
I'd think it's still something with the car as it was fine for a little while. Plus it's only showing the out of wack short term fuel trim number on bank 1. I think I'll swap 1-3 injectors next to see if fuel trims move to bank 2. At least that's free to try. If that doesn't show anything I'm stuck. I suppose professional smoke test next just to be sure, but I'm almost positive I don't have any leaks.
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At idle with my foot off the gas my '99 M3 sits at 17%/18% throttle. Not sure on the rest of the numbers though. When I get back from my trip I can see what my car reads for the rest of the parameters you posted to compare
small update. Took car into Crestwood Auto clinic in Madison for diagnostics. They hooked it up to their machine. Codes ran a little deeper than I could get with my scanner.
227, 228 Mixture Deviation Cylinders, 1-3,3-6
202 O2 Bank 1 control limit
242, 243 Misfire Cylinder 5,6
They said car is actually running fine under OEM bmw specs and wouldn't trip the CEL if it weren't for the SC, injectors, etc. I kind of suspected that. They said the tune likely needs to be redone. I perhaps lost it unplugging the battery? I've reached out to three tuners around here to see what they think and pricing for a new tune. Accumoto in Waunakee, Capitol Tuning, Performence Engine in Middleton if anyone has experience with any of them.
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