thx1138v2

It could be just the bulb.

I had a 2006 Silverado 4X4 with 5.3L engine. It had a device called a "power steering control valve" that fit somehow on the steering shaft. It's purpose was to boost the power steering when sitting still and it was hard to crank the steering wheel over and then reduce the boost when you got up to speed. It worked fine when it was working but when it went out is was a bear to crank the steering over either right or left. You might look into that

Have you reset the codes between fixes? That's when I usually get the P0300 codes. Once I get all the problems corrected the P0300 goes away.

For a temporary fix, pull the dome light bulbs. That will prevent it from draining the battery. Then find a manual for your year an body model and electrical schematics. You will need a voltage meter and how to use it to locate the actual problem. If that's not possible, you will need someone else to repair it.

2007 GMC Sierra C1500 4.3L Classic The code is "Multiple cylinder misfire." This one turned out to be a loose connection in the 3-pin connector on the ignition coil. It was driving me crazy with many different fixes that would last a day or 2 and revert back to the misfire and stalling. So check the coil connector first to either fix it or rule it out.

Go to to your auto parts store and pick up a spray can of "Mass Air Flow sensor Cleaner" ($12.00) and clean the Mass Air Flow sensor by spraying the grid with it. Give it a couple of minutes to evaporate and put it back together and try it again.

I have always used Slick50 in my trucks but I've noticed that the owner's manual for the 2007 4.3L I just bought says not to use any oil additives. I'm just curious why it says that? I assume it's something to do with the synthetic motor oil.

Well it looks like the EGR system has been removed. At least that's my take after looking for it for 2 days. I did go ahead and take a couple of photos. I should definitely get better gas mileage with the new CTS.

ACE Hardware couldn't make the key I have so I went to the dealership. It turns out that my key does NOT have a transponder in it so the dealer made me a plain key and it works fine. I haven't had any problems since I had the new key made but it definitely didn't cure anything. So I guess I need to replace the EGR valve. I can't find it on the internet You tube videos or stills. I may have located it on the driver's side right above the valve cover but I'm not sure that is it. I think what I'll do is remove the air inlet duct and take a picture of what I think is it and post it here. I'll do that in the morning because it's already 100F here and is supposed to get to 107F today.

Pure water sounds like a good idea but it's not because antifreeze has additives that give the mixture better adhesion to the metal in the water jacket and therefore better heat dissipation. Here's a graph I put together that you might find helpful.

I just got some interesting info from Ace Hardware, of all places. I took my key there to get a copy made and the guy told me that the key has a transponder in it that communicates with either the fuel pump or the ignition system, depending on the make/model. I don't know how the key gets its power but I suspect it draws a slight charge from the charging system. I suspect the truck sat for a long time before I bought it and the charging system for the key ran down and it was dropping out as I drove it. The longer I drove it the stronger the charge got so it has a stronger transponder signal now and its running just fine. Does anyone else have any info on this? I'm surprised but the symptoms match a poor transponder signal. I'll put a new Coolant Temperature Sensor (CTS) in it anyway to hopefully improve the gas mileage. I don't know, in light of the above info, if the SeamFoam is making any difference or not.

I'm shopping for another scanner. Any suggestions? I've heard the "open/closed loop" terms for years and still don't fully understand them. I'm a computer programmer by trade so it may be that is what is confusing me. Could you please explain the phrase to me. BTW, after determining that all of the problems were caused by carbon build up, I put a can of SeaFoam in the gas yesterday and drove about 60 miles. It seams to have cleared it up for now. I'll monitor it though. Any good/bad comments about SeaFoam in the gas as opposed to the crankcase?

I didn't think of that one. I did think of the CTS and the IAC. I'll look into it. Thanks.

No codes but I probably need a better OBDII scanner. My '94 was an OBDI and I never did get it working with the scanner I have. Recommendation?

I just bought a 2007 GMC Sierra 4.3L Classic. It runs rough until it warms up. It stutters and surges until it gets warm and then smooths out and runs much better when warmed up but still dies on occasion when stopped at stop light. This LU3 engine is new to me. I previously drove a 1994 GMC with a VIN Z engine for 30 years. Any help will be appreciated.