Fuel injectors are typically driven directly by power transistors in the engine computer. Relays are just not fast enough to provide the fine timing control needed. There might be an individual fuse for each injector soldered to the computer board, but I haven't ever looked at one for your model, and I've never seen injectors individually fused. Before chasing that, verify that the electrical resistance of the injector coil is the same as the other injectors. The typical resistance is between 100 and 1000 Ohms. If the coil resistance differs by more than 10%, replace the injector coil (it may be easier to remove the coil from a new injector and switch it with the old one than to pull the entire injector out and replace it, if not, change the injector). Shorts in the coil that lower the resistance are sometimes a problem.
Also check the injector cable for continuity. An easy way is with an ohmmeter that can read at least 20 Megohms. First, check the resistance between the terminals on a good cable. You should read a very high resistance - this is the leakage through the transistor and any protective components, and is some number between 5 and 20 megohms. The exact number doesn't matter, as long as you see something and it is not a short circuit (less than 1 Ohm). This verifies that the test will work (if it reads over-range, either your probe tips can't reach the contacts in the connector, or the test is otherwise not valid). Next, repeat on injector 1. If it reads open circuit (over-range), check the injector cable (note: an open fuse will give the same result as a broken wire).
Question edited for clarity.
Question moved to model category.
There are injector and also 'air injector' fuses. Not sure what the latter are though?
Press CTRL+F and type injector and press enter.
Backfiring can be caused by leaking valves, (compression leak test will show this), an air leak in the inlet manifold, incorrect timing. incorrect mixture or an air leak in the exhaust manifold.
Very undesirable as it can lead to engine damage.
Interference may be caused by non - resistor spark plugs. If you don't want to change your plugs for resistor plugs, you may be able to get an inline resistor for the antennae from your local electronics supply store, like radio shack. Failing that, you can buy a cb antennae with a built in resistor coil that will also do the job. If you buy the new antennae, go to a cb shop to have your antennae tuned to your cb - it will increase your range and clean up your sound too. Hope this helps, and please rate my solution!!
Time to get your test gear out and find out where the damage is.
(Replacement 'computers', in some vehiles, don't normally work unless they have been reprogrammed with the rest of the system).
Question edited for clarity, wrong type of break vs brake.
Question moved to model category.
Take it back to the shop. They have a duty of car to fix what you take it in for and not break anything else. Their scan tool should diagnose the issue in 5 minutes.
https://www.google.com/search?q=2006+GMC+Envoy+all+the+cluster+light+are+on
..
when you disconnected the battery you cleared all codes and your emissions[ smog/emissions need to run their cycles to be smog test ready as of now you will fail test ------https://smogcheckvacaville.com/general-motors-drive-cycle-for-smog-check/ ------------------https://repairpal.com/how-to-perform-a-basic-drive-cycle
It's a guess, but yes, you have one or more stuck injectors and when you power off the pressurized gas in the system is going into the combustion chambers and seeping past the piston rings. When you pull the relay, it is running on the fumes from the oil pan.
You need an auto electrician, a professional grade scan tool computer can diagnose in 30 minutes.
https://www.google.com/search?q=mobile+auto+electrician+near+me
..
If the headlamps on your 2001 GMC Sierra won't turn off when the truck is started, there are a few potential causes for this issue:
1. Faulty headlight switch: The headlight switch may be malfunctioning, causing it to remain in the "on" position even when the truck is started. A faulty switch can prevent the headlamps from turning off as intended.
2. Stuck relay: There could be a stuck relay in the headlamp circuitry, keeping the power to the headlamps constantly engaged. A stuck relay can cause the headlamps to remain illuminated even when the switch is off.
3. Wiring issue: There may be a wiring problem, such as a short circuit or a damaged wire, that is causing a constant supply of power to the headlamps. This can prevent the headlamps from turning off when the truck is started.
4. Daytime running lights (DRL) malfunction: If your Sierra is equipped with daytime running lights, there could be a malfunction in the DRL system. This can cause the headlamps to stay on at all times, regardless of the switch position.
To address this issue, you can try the following steps:
1. Check the headlight switch: Inspect the headlight switch for any signs of damage or wear. If the switch appears to be faulty, it may need to be replaced.
2. Check the relays: Locate the relays associated with the headlamp circuit and check if any of them are stuck or not functioning correctly. If a relay is found to be faulty, it should be replaced.
3. Inspect the wiring: Thoroughly inspect the wiring harness and connectors in the headlamp circuit for any visible damage or loose connections. If any issues are found, the wiring should be repaired or replaced as necessary.
4. DRL system troubleshooting: If your Sierra has DRLs, consult the vehicle's owner manual or a service manual to understand the DRL system's operation. Follow the troubleshooting steps outlined in the manual to diagnose and resolve any issues with the DRL system.
If you're unable to identify or resolve the problem on your own, it is advisable to consult a qualified mechanic or take your GMC Sierra to a reputable auto repair shop for further diagnosis and repair.
The jack to lift the vehicle is under the rear seats. Both seat bases, (the section you sit on) tilt forward to reveal the tyre iron and the jack. The jack is a 'bottle' style. You might need to twist the big twist nut on the side of the jack 1 or 2 turns counterclockwise to get it to come out of it's storage slot. Do this the opposite way around when putting it back as it stops the jack rattling around and annoying you.
Try this website as it shows the jacking up procedure in single steps.
https://www.carcarekiosk.com/video/2004_GMC_Envoy_SLT_4.2L_6_Cyl./jack_up_car/use_your_jack_to_raise_your_car
disconnect ur positive battery cable. make sure not to set alarm with remote. let set for about 5 minutes, this happened to my 2003 gmc yukon xl and it actually worked
JustAnswerhttps://www.justanswer.com > GMC Questions
Sep 3, 2022 - It is located behind the left side of the dash. Location diagram and directions to access are attached for you. Ask Your Own GMC Question. GMC ...
1 answer · Top answer: Hi! Welcome to JustAnswer. Thank you for contacting us for assistance with
Vehicle Historyhttps://www.vehiclehistory.com > questions > how-do-...
Apr 9, 2020 - The first thing You need to do is open the driver's side door, and sit down inside. Next, place Your key in the ignition, and turn it to the on ...
6 answers · Top answer: Resetting the 2003 Chevrolet Silverado security system is easy, and takes about 5 to 10 minutes. The first thing You need to do is open the driver's side ...
JustAnswerhttps://www.justanswer.com > GMC Questions
Jan 10, 2013 - 30 minute GM relearn procedure: 1-Turn ON the ignition, with the engine OFF. 2-Attempt to start the engine, then release the key to ON ( ...
1 answer · Top answer: HI, What is happening - is the security light staying on and truck not starting, or is the ...
JustAnswerhttps://www.justanswer.com > Chevrolet Repair
Jan 4, 2010 - Bump the key into the start position then leave it in the on position for 10 minutes, after 10 minute shut vehicle off for 5 seconds and ...
1 answer · Top answer: Ok, let me know. Thanks
..
Does the engine crank over and will not run or does the starter not crank? If no crank then check the battery and connections. Make sure the vehicle is in park. Possible bad starter or dirty or loose connections. If it cranks over but will not start the spray a little starter fluid into the throttle and try starting it. If it runs, then you have a fuel delivery problem. If it does not run, then an electrical problem may exist and you will need a scanner to help find the problem.