Hi, My 94 Bravada has a strange (to me) problem. A month or so ago, the PCM indicated code 32 - EGR valve. The idle was uneven and the car would sometimes stall when stopped. I tested the EGR valve, the position sensor resistance was slightly out of spec when the valve was closed, so I replaced it. The code went away and the car ran fine after that. Then, a couple of weeks later, it suddenly it started running extremely rough on idle. Much worse than before. No check engine light. Low vacuum, no brake boost. I suspected the booster was leaking. I disconnected the vacuum hose and plugged it. Still very rough idle, smoothes out at higher RPM. Next, I put a scope on the injector leads and measured current. I saw the normal injector pulses running at the same rate as the ignition, but also saw random narrow pulses between the normal pulses. Any ideas what is going on? Is this a PCM problem? The ignition looks good, no extra pulses there. The injector assy was replaced under warranty a couple of years ago due to a leaking regulator. The fuel pressure measures good and holds after the engine is turned off, so the reg must still be good.
Thanks,
-- cb