DSM Injectors = Code 12, EGR system?
04-09-2003, 08:53 PM
#1
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DSM Injectors = Code 12, EGR system?
Problem: Everytime I'm crusing in the range of 2k to 3k RPM, I get a Code 12(EGR System)CEL when running DSM 450cc injectors. And also cold start hesitation.
I've tried going rich down to -20% and lean up to -50%, but I still get the CEL.
Swapping the stock injectors back in stops the CEL from appearing.
So ok, it must be a bad/clogged injector right? took the injectors to RC Engineering for testing.. results were excellent; 2 injectors checked out at 450cc, 1 at 449cc and last one at 448cc, total set variance of 0.4% of rated flow rate!!! These injectors are in perfect condition. Resistance checked out at 2.7ohm for all 4. I asked the RC Engineering tech what could be causing the EGR CEL and he said it could possibly be my automatic transmission?? And that I can try disconnecting the EGR hose and plugging up the hole in the valve cover and putting in a resistor on the EGR sensor so the ECU will always think it's working properly.
Questions: What is the resistance(ohms) for stock Honda peak & hold injectors?
Would disconnecting my EGR hose and plugging the outlet on the valve cover be bad for my engine?
Is the tech right about the automatic transmission or is he just bullshitting??
I really need some help cause this is the main concern I have before installing my turbo..
91 Accord, everything's stock and using an S-AFC II.
I've tried going rich down to -20% and lean up to -50%, but I still get the CEL.
Swapping the stock injectors back in stops the CEL from appearing.
So ok, it must be a bad/clogged injector right? took the injectors to RC Engineering for testing.. results were excellent; 2 injectors checked out at 450cc, 1 at 449cc and last one at 448cc, total set variance of 0.4% of rated flow rate!!! These injectors are in perfect condition. Resistance checked out at 2.7ohm for all 4. I asked the RC Engineering tech what could be causing the EGR CEL and he said it could possibly be my automatic transmission?? And that I can try disconnecting the EGR hose and plugging up the hole in the valve cover and putting in a resistor on the EGR sensor so the ECU will always think it's working properly.
Questions: What is the resistance(ohms) for stock Honda peak & hold injectors?
Would disconnecting my EGR hose and plugging the outlet on the valve cover be bad for my engine?
Is the tech right about the automatic transmission or is he just bullshitting??
I really need some help cause this is the main concern I have before installing my turbo..
91 Accord, everything's stock and using an S-AFC II.
04-09-2003, 09:07 PM
#2
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Join Date: Jan 2003
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Re:Larger Injectors = Code 12, EGR system?
Some more info.. I have the blue wire mod done with my S-AFC so I can monitor the O2 voltage... with stock injectors the readings jump around from .2v up to .9v through the entire range(normal stoich voltage when cruising), but with the DSM injectors, the voltage reads .04-.07v anytime the RPM is steady above 2k and the same .2v to .9v from idle to 2k RPM. At WOT or under hard accelaration, it reads a steady .7v to .8v(stoich for N/A)
I know the blue wire mod's not that accurate since it's using the stock O2 sensor.. but it shouldn't drop that low when using the DSM injectors right?
Also when I rev and hold my throttle around 2.5k RPMin neutral/park, it sometimes jumps up and down about 500RPM. Any ideas on that? I'm really getting furstrating with this
I know the blue wire mod's not that accurate since it's using the stock O2 sensor.. but it shouldn't drop that low when using the DSM injectors right?
Also when I rev and hold my throttle around 2.5k RPMin neutral/park, it sometimes jumps up and down about 500RPM. Any ideas on that? I'm really getting furstrating with this
04-12-2003, 02:50 AM
#5
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Re:DSM Injectors = Code 12, EGR system?
Well, you have an EGR lift position sensor I'll bet.... If I had the Helms handy I'd take a peek, because diagnosis procedures would give it away in a heartbeat.
I bet EGR system is partially controlled by vacuum. EGR is typically used on light to medium throttle to cool combustion temps to prevent formation of NOx gasses. I'm assuming that the ECU thinks the EGR valve will be open due to the "vacuum" readings it gets from the MAP under WOT and even low boost. EGR lift under WOT = CEL or no EGR lift under WOT when ECU assumes vacuum = CEL.
I bet EGR system is partially controlled by vacuum. EGR is typically used on light to medium throttle to cool combustion temps to prevent formation of NOx gasses. I'm assuming that the ECU thinks the EGR valve will be open due to the "vacuum" readings it gets from the MAP under WOT and even low boost. EGR lift under WOT = CEL or no EGR lift under WOT when ECU assumes vacuum = CEL.
04-12-2003, 02:42 PM
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Re:DSM Injectors = Code 12, EGR system?
Originally Posted by Joseph Davis
Well, you have an EGR lift position sensor I'll bet.... If I had the Helms handy I'd take a peek, because diagnosis procedures would give it away in a heartbeat.
I bet EGR system is partially controlled by vacuum. EGR is typically used on light to medium throttle to cool combustion temps to prevent formation of NOx gasses. I'm assuming that the ECU thinks the EGR valve will be open due to the "vacuum" readings it gets from the MAP under WOT and even low boost. EGR lift under WOT = CEL or no EGR lift under WOT when ECU assumes vacuum = CEL.
I bet EGR system is partially controlled by vacuum. EGR is typically used on light to medium throttle to cool combustion temps to prevent formation of NOx gasses. I'm assuming that the ECU thinks the EGR valve will be open due to the "vacuum" readings it gets from the MAP under WOT and even low boost. EGR lift under WOT = CEL or no EGR lift under WOT when ECU assumes vacuum = CEL.
Furstrating 
04-12-2003, 02:45 PM
#7
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Re:DSM Injectors = Code 12, EGR system?
Possibly the wrong amount of EGR lift for the vacuum readings the engine is seeing? Get some service literature for it, it should help.
FWIW, some people have been known to upgrade their ECUs to P06/P28 from the Civics, and chip them for correct fuel/ignition. That might be something for you to look into.
FWIW, some people have been known to upgrade their ECUs to P06/P28 from the Civics, and chip them for correct fuel/ignition. That might be something for you to look into.
04-12-2003, 02:51 PM
#8
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Re:DSM Injectors = Code 12, EGR system?
Originally Posted by Joseph Davis
Possibly the wrong amount of EGR lift for the vacuum readings the engine is seeing? Get some service literature for it, it should help.
FWIW, some people have been known to upgrade their ECUs to P06/P28 from the Civics, and chip them for correct fuel/ignition. That might be something for you to look into.
FWIW, some people have been known to upgrade their ECUs to P06/P28 from the Civics, and chip them for correct fuel/ignition. That might be something for you to look into.
I looked into an ECU swap because I wanted to go Hondata first, but Erick from Ericking's racing(fastest Civic in the world) told me I can't because I have an automatic and he doesn't recommend it. I called Hondata also and they said the same thing. But they did both say that I could purchase the P28 and a Hondata unit to test it out.. like most people I'm not into spending $600+ to test something that might not work.
04-13-2003, 12:44 AM
#9
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Re:DSM Injectors = Code 12, EGR system?
Oh, automatic.
Get a copy of a REAL service manual if you can, a Helms manual, and see what it says. If you can get my copies of EGR troubleshooting I'll try to help you bypass the EGR problem as the ECU sees it - I just have to know how the ECU sees it.
Get a copy of a REAL service manual if you can, a Helms manual, and see what it says. If you can get my copies of EGR troubleshooting I'll try to help you bypass the EGR problem as the ECU sees it - I just have to know how the ECU sees it.
05-16-2003, 09:59 PM
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Posts: 43
Re:DSM Injectors = Code 12, EGR system?
BFTD thread.
I thought I had no problems when I installed my 390cc injectors and using AFC... but I was wrong...the engine light came on, this happened when rpm was moving between 2800 - 3000. Check the code, and what do you know...code 12, EGR, same issue as this thread... The engine starts with no hesitation and seems to be running fine with no knocking or odd sounds when taking a load...
91accordlx or anyone, you figure this out yet? I'll be troubleshooting this weekend. ugh!
BTW, the DSM injectors sound loud at idle (ticking sound)...is it normal for the injectors to be much louder than stock?
Any further info would be great.
tx
Curtis
I thought I had no problems when I installed my 390cc injectors and using AFC... but I was wrong...the engine light came on, this happened when rpm was moving between 2800 - 3000. Check the code, and what do you know...code 12, EGR, same issue as this thread... The engine starts with no hesitation and seems to be running fine with no knocking or odd sounds when taking a load...
91accordlx or anyone, you figure this out yet? I'll be troubleshooting this weekend. ugh!
BTW, the DSM injectors sound loud at idle (ticking sound)...is it normal for the injectors to be much louder than stock?
Any further info would be great.
tx
Curtis
