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Old 09-20-2012, 01:44 AM   #1
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Default backfiring out exhaust and popping on decel

Ok so my car is running again. I am experiencing a lot of load backfiring and popping on decel. My exhaust also sound like I have miss (might be the 550 injectors idleing rough) I also noticed removing #4 wire the engine does not really change much at idle but the spark is there for sure jumping to the valve cover so I have spark.
Is this a tunning issue or an injector issue?
My searched about back fires say rich, to retarded timing and everything in between.
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Old 09-20-2012, 09:33 AM   #2
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use overrun.
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Old 09-20-2012, 10:38 AM   #3
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I have over run on rpm greater than 1600
oa lower than 30
tps lower than 2%
coolant greater than 90
after no delay
delay ego 1
return fuel 1200
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Old 09-20-2012, 12:00 PM   #4
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what are you AFRs when you lift then? it should be pegging lean.

what are your idle AFRs?

did you have your 20 year old injectors serviced?
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Old 09-20-2012, 12:58 PM   #5
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Whatever you do, do not post a log.
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Old 09-20-2012, 03:24 PM   #6
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No I have not had the injectors serviced. Would a clogged injector do this (I will prob send the 550 out to be serviced and run the 460cc till they get back). I am also worried about the wires. I am going to try and swap over to the 04 coils since I know the engine runs now.
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Old 09-20-2012, 03:27 PM   #7
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Quote:
Originally Posted by 90 Turbo View Post
No I have not had the injectors serviced. Would a clogged injector do this (I will prob send the 550 out to be serviced and run the 460cc till they get back). I am also worried about the wires. I am going to try and swap over to the 04 coils since I know the engine runs now.
I have some 550 EV1s that I'm using on Friday and taking-out on Saturday.
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Old 09-20-2012, 03:29 PM   #8
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Send me your log and an MSQ and I'll look at it tonight. If you can bring the car over tonight, I'll play with it and see if I can get it running. We really need a log and the MSQ to do anything. Tell me you have some-sort of a conductive metal grounding the coil to the engine.

Get the 01 coils on it now, change the dwell settings, and try again.

I would have helped you by now but as I told you, I've been crazy busy. This weekend is good for me to help out.

Edit:
My EV14s may be at my house right now
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Old 09-22-2012, 12:44 PM   #9
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Something is whacked-out in enrichments:

TPSDot is effectively disabled (0%) but it appears to be doing something. What could cause this?
Attached Thumbnails
backfiring out exhaust and popping on decel-hrzfl.jpg  
Attached Files
File Type: msl 2012-09-20_21.29.05.msl (891.8 KB, 91 views)
File Type: msq 3.msq (83.9 KB, 77 views)
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Old 09-22-2012, 01:05 PM   #10
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your injectors are leaking. youre completely rich when you lift and your PW is dropping to 0...so no fuel is getting injected, but it's pouring in on its own.
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Old 09-22-2012, 01:31 PM   #11
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What's up with the TPS noise? My daily doesn't do this. We calibrated again and we keep getting a 0% to -2% fluctuation in the gauge.
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Old 09-22-2012, 02:52 PM   #12
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I also have changed the injectors once from the 550 which were doing same thing to 460 which are now still doing same thing.
Here is a log of the problem I am still having since swapping to 04 coils. By the way I had to hook mine up opposite of what I have seen on here for the signal wire to coils:

solid brown to blk and yellow
brown and yellow to brwn and white


So here is what it is doing fine below 3k but if you get on it some like 40% throotle it sputters bad. It feels kind of like when you burn something to the ecu.
Not cool.

Also I changed the max dwell to 3.2 and left cranking dwell at 6 is that right for the 04 coils. I know dwell is supposed to be 3.2 but is that the max dwell?
Attached Files
File Type: msl 2012-09-22_12.15.54.msl (246.7 KB, 97 views)
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Old 09-26-2012, 07:27 PM   #13
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Well the engine let go. I think one of the valve was sticking and finaly came loose. tried to drive a mile to store but did not make it only made it worse. will report exactly what happened once I open engine in a few months.
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