I retrofitted an early model SBC 415 cu in with a speed density TPI and am having trouble with the headers glowing. It seems to be a rich condition due to the smell of the exhaust. How can I tell if I am in closed or open loop mode? I am new the fuel injection scene but am learning fast, I know the ECM adds extra fuel during warm up and until the engine reaches operating temp, could my engine not be reaching operating temp and therefore never changing to closed loop?

What temp do I need to get it to? My PROM programmer tells me the fan is set to come on at 204*, is this the temp the engine needs to be before it switches over?

My O2 sensor is located about 12" from the collector on my block hugger headers, I am almost positive it is getting hot enough to work.

Any suggestions, the glowing is not that bad but it is enough to bother me, I am running 24# injectors, we had the same problem with 19#.

Thanks,

Mark

 

Bro, if your headers are glowing, I would SERIOUSLY look into your timing. I have only seen glowing exhaust when the timing is severely retarded.......

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Black 1983 Trans Am
350 Cross-Fire Injection
T5 World Class
3.42 Locker
7747 ECM
Flowtech Headers
!Cat
Factory 98 WS6 muffler (oval tip)

 

Definately check the timing and usually glowing headers is a sign that it's running too lean, not too rich.



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1987 Camaro IROC-Z
350 TPI (L98), HyperTech Airfoil, K&N Filters and modified airboxes, AC Delco RapidFires, Taylor SpiroPro 8mm wires, Energy Suspension polyurethane bushings for front and rear LCAs and sway bars, KYB struts and shocks, BFG g-Force Z-rated tires, MAC STB, MAC SFCs, JET low temp stat, CarSound Hi-flow Cat, 3" Mandrel-bent pipes, Flowmaster muffler, Corvette Servo, TransGo Shift Kit, Corvette 2000 Stall, TruCool LPD tranny cooler, T-tops.

2001 Sunfire GT
2.4L, 5-speed, K&N cone filter, interior detailing, 200W Monsoon Sound System (8 speakers), Silver Metallic exterior with grey interior.

Web: http://www.angelfire.com/on3/whitelightening

 

Do you have a scan tool? That is the best way to find out if you are running rich or lean. What eprom are you running? For a 415, you are most likely to find that you are rich in certain areas and lean in others unless you have a custom eprom.

For an SD application, you need to modify the eprom to know about the extra displacement and the larger injectors. Then you need to monitor the ECM in "normal driving situations" to determine what your "mixture" is based on RPM/Load on the VE tables within the eprom.

A good scan tool will tell you when you are running in Closed or Open loop and let you know if you are running rich or lean.