newbroncorox
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My vehicle is a 1996 Ford Bronco with a 5.8L engine. It is recently acquired, and I've been trying to get it to pass emissions. It also has an OBD II computer, the only Bronco year to have that new computer, which seems to be the source of my problems.
Here's the recent history. When I bought it a few weeks ago, it ran great, but the OBD II was kicking out some codes, one of which was P1351 (plus another code I don't have, but it went away), so it wouldn't pass the emissions test. Then, it began not starting intermittently, getting worse until it wouldn't start at all. I'd turn it on, the engine would turn over, but not start. There was no spark. I replaced the coil, still no spark.
We suspected the Hall effect pickup sensor in the distributor, so we replaced the distributor (cheaper and easier than just replacing the pickup sensor), and now it starts and runs every time. The engine doesn't run well, though, and the engine makes a couple of different sounds, for example when going over 40 mph, seems like the timing is off, and there's pinging. The timing is probably off a little from installing the new distributor (though we marked the position of the distributor and rotor carefully and got the new distributor to line up nearly perfectly), and that could certainly result in the poor running, but I think maybe the engine computer isn't working and making timing adjustments.
I borrowed a diagnostic tool for OBD II from Autozone. It read a code (P1351, ignition) the first time I used it, but after using it again, it wouldn't read anything at all (I think because the tool's frayed wires shorted out the computer or something.) A manager at AutoZone tried twice more at later times with different tools and it was unable to connect or read anything. There is no power and/or signal coming out of the OBD II port in the cabin. We checked the fuses that were indicated as being for the powertrain control module, and replaced one, because there was a 30 amp fuse where a 20 amp was supposed to be. (The problem with being able to read OBD II codes first happened before we replaced the distributor, and after we replaced the distributor and got it to run, there are still no OBD codes.)
So I think the problem is my computer (powertrain control module), but I don't know what, and it's a very complicated to figure out what diagnostics to do, even based on the extensive repair manual we bought (Haynes). Maybe the PCM has no power, maybe the PCM has been fried, or maybe just the ODB II output has been fried. If anyone has any idea what's going on, I'd appreciate some advice.
Here's the recent history. When I bought it a few weeks ago, it ran great, but the OBD II was kicking out some codes, one of which was P1351 (plus another code I don't have, but it went away), so it wouldn't pass the emissions test. Then, it began not starting intermittently, getting worse until it wouldn't start at all. I'd turn it on, the engine would turn over, but not start. There was no spark. I replaced the coil, still no spark.
We suspected the Hall effect pickup sensor in the distributor, so we replaced the distributor (cheaper and easier than just replacing the pickup sensor), and now it starts and runs every time. The engine doesn't run well, though, and the engine makes a couple of different sounds, for example when going over 40 mph, seems like the timing is off, and there's pinging. The timing is probably off a little from installing the new distributor (though we marked the position of the distributor and rotor carefully and got the new distributor to line up nearly perfectly), and that could certainly result in the poor running, but I think maybe the engine computer isn't working and making timing adjustments.
I borrowed a diagnostic tool for OBD II from Autozone. It read a code (P1351, ignition) the first time I used it, but after using it again, it wouldn't read anything at all (I think because the tool's frayed wires shorted out the computer or something.) A manager at AutoZone tried twice more at later times with different tools and it was unable to connect or read anything. There is no power and/or signal coming out of the OBD II port in the cabin. We checked the fuses that were indicated as being for the powertrain control module, and replaced one, because there was a 30 amp fuse where a 20 amp was supposed to be. (The problem with being able to read OBD II codes first happened before we replaced the distributor, and after we replaced the distributor and got it to run, there are still no OBD codes.)
So I think the problem is my computer (powertrain control module), but I don't know what, and it's a very complicated to figure out what diagnostics to do, even based on the extensive repair manual we bought (Haynes). Maybe the PCM has no power, maybe the PCM has been fried, or maybe just the ODB II output has been fried. If anyone has any idea what's going on, I'd appreciate some advice.
/emoticons/
