oilcanhenry

Never hurts to check compression values. They should be within 15 percent of each other. if not, put a small amount of motor down them, and see if any change occurs.

02sh!tboxSilverado

all the cylinders are at 148-154 on compression readings. Had some plugs that looked bad. Which expected with the misfiring. They were new too. But put brand new iridium plugs in and runs better on the six or culinders. Lol. New wires went on as well. So it’s either in my coils. Which I have swapped out with 2 other sets I have and no change. Or it’s a fuel problem. My injector code went away so I’m thinking I have clogged injectors. Fuel pressure is around 50+ so I know it’s getting fuel

Gumby22

Fuel injectors open and close using magnetic induction, produced by a solenoid coil, and there’s no direct electrical connections with the needle valve inside the injector body. It’s operation is identical to linear IAC and EGR valves or stepper motors.

The P0200 refers to the injector control circuits - it sets when the PCM detects an incorrect voltage level on the injector control circuit. Possible causes include inadequate battery voltage, short to ground, short to voltage, or open or high resistance in the control circuits - this includes problems internal to the injector solenoid coils, but not the needle valve that actually opens and closes.

The valve could be stuck open or closed and as long as the solenoid coil/control circuit is in tact the PCM is none-the-wiser.

02sh!tboxSilverado

That was one of my big questions that I couldn’t seem to get a direct answer to. Thank you. So if one or more injectors are stuck open or closed it won’t throw the code but would still cause the misfire problem. I got al the stuff I need to pull them all out and test them and clean them. And I have multiple extras sitting around from last 2 motors that I’ll probably just test and clean find a good set of 8 and swap them all out thank you for the responses. I’ll update as soon as I have a chance too and it quits raining

02sh!tboxSilverado

Thanks everybody for the help finally tracked it down to 3 dead injectors. Finally pulled them all out and tested individually. After 6 months of sitting and changing the motor and trans I got it running. Got to make it all of 15 miles before the trans destroyed itself. Welcome to my misery of this ****box.

oilcanhenry

Compression ratios are within tolerances, so that is not an issue. Yes, it might be getting fuel, but 50 PSI is on the low side. 55 to 62 PSI is ideal. Iridium plugs are the best, I agree, and only use them in vehicles I am working on, including my own. I would advise you to use some Techron Complete, Seafoam, or Lucas fuel injector cleaners.

Then take it out for an "Italian" tune-up out on some safe, but lightly used road with no police, and slam it to the floorboard. and get your motor up well past 5000.RPM's for at least a mile or more. I am not advising you to break the speed laws, so you can do the same, leaving your vehicle out of overdrive. It's best if you do this a while after adding the fuel injector cleaner to allow it to soak the injectors down real good and do some cleaning beforehand.

Note: I am sorry that your transmission went out on you. If you can't repair it or replace it yourself, my advice is to use Yelp to find a good shop that can overhaul it, and do a very good job doing so.

02sh!tboxSilverado

I went out amd did the Italian tune up haha, I put sea foam in the tank and everything motor wise is running great. Plenty of power and response. Thanks for all the help again.

regards to the trans, I have a great shop here locally that I’ll either have rebuild mine or buy one from them for core swap. Gotta love those 4l60’s. I lost od, won’t shift to it anyways. And long forced shift into third. Same exact thing my last one did. But the last one made it 330k miles. Idk what this one had but it only lasted for 15 miles for me