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Wont Pass Emissions?

6

65newguy

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Location
Denver, CO
I am new to diesels and the 6.5LTD. I recently bought a 1995 Chevy K2500 with the 6.5L TD that was not running. Installed used motor and got truck to run. My issue is the major black smoke, present from half to fwot. Truck failed emissions horribly, limit is 35% opacity and at 40 to 60 MPH mine read 89% roughly.

Installed;
MArine Injectors
Remote Location PMD w/ #9 resistor
Heath Turbo Master
K&N Air Filter
Attempted To Adjust Injection Timing, No Luck or Change!

I have notice my boost pressure is reading 11psi at idle and up to 19psi while driving. Stock chip, turbo, exhaust, intake, and no intercooler. I have read that the stock boost should be 5-8 psi.

Curious if you will get different readings with different scanners?
Why would my boost be so extreme?
Could I have a ECM problem?
Could a ECM problem cause this over fueling problem(Black Smoke)?

Does anyone have any thoughts or suggestions?
 
Boost is definately an issue. At idle you should have basically zero boost. Black smoke usually equals too much fuel or not enough air. Are you sure you didn't leave a rag in the intake or something blocking airflow?
 
What scanner were you using? On most scanners boost will read atmospheric pressure and the boost amount will be added to that. Peak boost on these engine should be roughly 1 1/2 atmospheres, so 14.7(sea level atmospheric) + 7.35 which will give you roughly 22 on the scan tool. Keep in mind though as you go up in altitude your boost will go up slightly to compensate for the difference if your using the stock system. Since I see your sig says DENVER you should see roughly 12-12.2 for pressure with the engine off or at idle. So 8 pounds of boost would read out as roughly 20-20.2 on a scan tool. Do you have an actual boost guage on this truck? If so what does it read?
 
Bad MAP sensor, causing the PCM to think it has more boost than it does. Who's injectors did you put in, what is spring lewngth setting for your TM, that boost level gage or scan tool reading?
 
Thanks for quick response!
ak diesel driver - Didn't remove the upper intake plenum during install so not for sure but don't think there is any blockage!
THEFERMANATOR - I am using a older OTC Monitor 4000 Enhanced. (OBD1) My atmospheric pressure reading on the scanner reads 24 inhg all the time, seems extremely high to me. I have replaced the MAP sensor (in intake plenum) with no change! I have not replaced the Baro sensor on the firewall. Is there any way to test that sensor? And does it only take a reading at startup or constantly. I have purchased Boost and Pyro Gauges but have not installed yet!
Turbine Doc - I purchased the Herzog marine injectors and PMD from Pensacola Diesel. Price was a big factor. Also I seem to have seeping from the bottom of each injector where the gasket seals to the head, Any thoughts? I have the TM spring length set to 2.5 inches as recommended and moved to 2.25 to see if there was a change, no change. Scan Tool.
 
okay your boost readings at idle and hiway with scan tool are reading pressure as PSIA not PSIG so you need to subtract out PSIA say 14.7 to know how much boost your gage will see.

Hate to say this because they are friends of mine, but I heard on another site PD's injectors were having some issues, you may want to call them.
 
Turbine Doc said:
okay your boost readings at idle and hiway with scan tool are reading pressure as PSIA not PSIG so you need to subtract out PSIA say 14.7 to know how much boost your gage will see.

Hate to say this because they are friends of mine, but I heard on another site PD's injectors were having some issues, you may want to call them.
Click to expand...

According to his sig TD he is in DENVER which would make it roughly 12.0-12.2, not 14.7 for sea level. Also keep in mind that 94-95 F engines utilize 2 MAP readings whereas 96+ F engines had 1. Your BARO reading will be the firewall mounted sensor, but your boost reading is in the intake. Your 24 on the BARO sounds pretty close for the altitude in Denver, but the 11 on your boost is low. I wouldn't think this would cause your issues though as the 11 would make it think it is at higher elevations. I don't remember if the 6.5 ECM pulls fuel until boost comes in or not at altitude. I would definately be suspect of injectors in this instance.
 
Thx Ferm, been a long time since I had to compensate for anything but sea level and I missed that tidbit of info, since both sensors work pretty much the same with key on engine not running should also read the same, there is a boost low condition, possibly as it tries to rectify a baro/boost mismatch it is pulling fuel since tier 1 defense is to adjust boost (it can't since a TM is being used to regulate that now), and tier 2 defense if the condition isn't rectified is to pull fuel. Mite be worth throwing a new MAP/boost sensor as it is off range of where it should be, another thought just occurred possibly PCM is overfueling to get the boost up vs a defuel condition, a working EGT would be handy rite about now.
 
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