code 42 only sets if there is a wiring issue with the bypass (black/tan) or est (white) wires. could be an open or a short to ground, bad connection at the ICM, or stray voltage from a plug wire touching one of the wires or a bad plug wire or distributor cap letting voltage out and it is causing...
under the truck behind the fenders are the cowl drain exits. you may need to remove a plastic cover to see them. but you need to pull debris, flush from top, pull debris, and repeat until all the debris is removed. both sides.
the cap will come out with a small screw driver or a pick. you shouldn't need to drill it out.
better question is - what are you trying to accomplish by adjusting the min idle air screw? the IAC controls the actual idle speed.
My 90 burb TBI has no pressure releasing when I open the gas cap. I'd check out cannister under the hood to make sure it is all connected right and that the vent line from the tank isn't plugged. I think there was a thread on here somewhere about the cannister set up. It's also covered in the...
thanks for that info. I have a L05 engine, so never looked into that for the other engines.
All the GM manuals are available in the reference library on this forum. they are a GREAT resource!
my 350tbi (1990 burb) fires in 2sec, maybe 3 sec, on a cold start every time. it fires instantaneously on a hot start every time. fuel pump is newish, and it did the same before and after the pump swap. I don't think the TBI system retains any residual pressure. I always just chalked it up to...
I have 3.73 in my v1500 burb (350tbi and 4L60), and don't think the cost is worth it to swap to 4.10 for ~32in tires. Right now i have a cruising RPM of about 2100rpm on the hwy at 75mph and it is certainly plenty serviceable around town also. Although I'd prefer 4.10, its just not that big a...
the pressure regulator controls the pressure between the pump and the regulator that feeds the injectors. it bleeds off any excess pressure into the return line. so you can measure pressure just after the fuel filter at the flex line (where I have my adapter installed) or at the TBI on the...
code 42 is usually a bad ICM, or stray voltage somehow getting to the white (EST) or tan/black (bypass), or an open or short (sounds like an intermittent issue) in one of those 2 wires or at the ICM connector.
On mine, there is a noticeable difference in the sound of the air when on Max and the door switches from fresh air to recirculate air from inside the cabin. You can definitely hear it change from ac to max ac. If it stopped recirculating, I'd be looking at the vacuum line and the pod that...
There might be a sticker under the dash by the ECM that has the number in case somebody installed the wrong one? But I'd think you'd have larger drivability issues with the wrong computer.
Could also be that they swapped ECM with the new body style and those got a different computer. Might have...
It sounds like it is likely electrical, and could be the motor or an alternator issue. But next time try to see if you can get under the hood and check the actual motor to make sure it is not doing anything vs just feeling at the vents
right after key on, yes. it primes for 2-3 sec when key on and then the pump turns off. I don't know if it should drop to 0 during cranking, but that doesn't seem correct. have you looked in the emissions and drivability manual?
Are you missing the vac line that goes to the vacuum reservoir off of that T just downstream of the check valve. I dont recall my setup having a plugged T there. Or does the other line off the other T head that direction to the reservoir? Vac should be good at idle, though.....so I'd expect that...
not sure if the OP has specified if the blower stops or just the airflow out of the vent stops. also, try the blower on high because that bypasses the relay.
turning the key to ON will prime the pump for a couple seconds. after the prime, the pressure will bleed off. not sure why the pressure drops to 0 for the first couple seconds of cranking. I've never done that test with mine, but intuitively it seems like the pressure should be there during...
1 looks like the wire to test the fuel pump with 12v that bypasses the relay.
2 I am not sure. I might run out and check my 90 burb in a bit and look around.
3 looks like the tach signal off the distributor.
4 looks like the temp sensor for the cluster. should go between plugs 1 and 3 in the...
I've messed with mine a bit, and i think the door is warped. So the vent settings are more like bilevel. Bilevel is like 75% floor. For AC, having a vent/floor split really is OK as it cools off high and low up front and the rear comes in high from the back. On heat, it seals up tight and only...
could be module. could be a wiring harness issue, could be stray voltage from a cracked distributor cap, could be plug wire sitting on ICM wire. but code 42 means an issue in the EST (white) wire or the bypass (tan/black) wire (open, short, seeing voltages it shouldnt) or the connector at the...
I was thinking to ONLY power cycle the fuel pump instead of cycling the key. Just trying to narrow it down. link to new ECM above. that's the same vendor I got my spare ECM from when I thought maybe my ECM was bad.