OBD lean reading
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From: Issaquah, WA
OBD lean reading
My truck reads lean on the diagnostic codes. Its a EFI 302 with headers, and the air pump disconnected. I've read that a dirty/bad injector and/or exhaust leak (among other things) can cause that. Is there a way to determine if I have a fouled injector? There isn't an exhaust leak that I can perceive.
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From: Virginia
You 1st have to wonder if the oxygen sensor is working. Second, where is the oxygen sensor located since you have headers. If you have long tube headers, then mounting it down low in the collector may cause a problem(too cool).
If you want to check for a leaky injector, install a fuel pressure gauge and then turn the truck off. If the fuel pressure drops rapidly, a leaky injector could be the cause. You could also pull the sparkplugs and see if any look wet or fouled with fuel.
If you want to check for a leaky injector, install a fuel pressure gauge and then turn the truck off. If the fuel pressure drops rapidly, a leaky injector could be the cause. You could also pull the sparkplugs and see if any look wet or fouled with fuel.
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From: Issaquah, WA
Its a new sensor, but I think it is down farther on the pipe. In fact, its not on the header (long), but on the exhaust pipe. Where should it be mounted on the header, on one of the individual tubes?
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From: Virginia
You really should have shorties with the bung already welded up close to the engine. Since you do not have much choice in that area, except spending some money for new headers, I would leave that for now and see if you have any fouled plugs. That's cheap and easy.
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From: Virginia
Summit SUM-G9035 - Summit Truck Headers - summitracing.com
Flowtech 91627FLT - FlowTech Shorty Smog Headers - summitracing.com
Those are a couple of shorty headers. They do not mention the bung in the collector, so the bung must be located in the factory y-pipe that bolts to these headers.
Flowtech 91627FLT - FlowTech Shorty Smog Headers - summitracing.com
Those are a couple of shorty headers. They do not mention the bung in the collector, so the bung must be located in the factory y-pipe that bolts to these headers.
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From: Issaquah, WA
Thanks for the suggestions. They got me pointed in the right direction. However, both those headers are listed for '87 at the earliest. My truck is a '85. Do you know if those would still work?
Also, I don't have the stock exhaust on it now. I have a Dynomax kit that matched the long headers I got from Summit. The O2 sensor mounted on the manifold originally. If those headers would work on mine, I think I found a dual exhaust kit that is meant to bolt up to the stock manifold (HOK-16665HKR), so it might fit the shorty header. As for the O2 bung, I guess I can weld one on shorty's collector.
Also, I don't have the stock exhaust on it now. I have a Dynomax kit that matched the long headers I got from Summit. The O2 sensor mounted on the manifold originally. If those headers would work on mine, I think I found a dual exhaust kit that is meant to bolt up to the stock manifold (HOK-16665HKR), so it might fit the shorty header. As for the O2 bung, I guess I can weld one on shorty's collector.
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From: Virginia
If that's the case, then you could get someone to custom bend some pipes to hook up to the exhaust you have now. I don't see why 87 up headers won't fit, but I have never tried it either. Some of the long tube headers fit from 80 to 96.
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From: Virginia
The factory used heated sensors in some applications. I was just looking at a 95 5.8 diagram, and it has two heated sensors. The sensor has 4 wires. Two for the signal, and two for the heater. The heater gets 12 volts with the key on.
