07Silveradooo

I'm still having problems with the check engine light on my 2007 Silverado. Again if I'm merging on the highway and bring the rpms over 4500k the check engine light will start blinking and sometimes it'll stay on. When this happens there is a noticeable difference in power and seems more sluggish. I've had the car looked at and the scanners won't work with the car when they are plugged it. I've tried 3 scanners and none of them would read the codes. Now I have a new problem, with the battery. I was working on the car the other day with the radio on and I went to start to start it and the battery was completely drained...no problem I jump started it and didn't have any problems. However the next 3 days the battery kept dying without anything left on such as the lights, my radar detector, and my phone and zune. I replaced the battery with a new one, but I was suspecting the altenator as well, because my old car had similar issues. I'd be running off the battery and it was a new battery until there would just enough voltage to have dash lights. But not enough to start the car. I haven't had any issues yet since I replaced the battery(it's been almost 24hrs) and also the positive cable keeps getting heavily corroded. I cleaned off the connection on sunday and it was pretty badly corroded again yesterday. I've cleaned the positive lead about 5 or 6 times in the past 6 weeks because of the corrosion. Any ideas again would be awesome! -Karl

StrictlyChevy

Usually a blinking CEL is a serious situation. Even if it comes and goes or only happens at certain times, its not good. Almost all of the time a blinking CEL is caused by a misfire code. If you continue to drive without fixing the problem is going to cause many more problems. Have the spark plugs even been changed? If not I would pull one and see what it looks like, that very well could be the problem. And if changing the spark plugs I would change the wires too.

Now if you are losing power or it seems to be sluggish this could also have to do with the throttle body. There is a throttle sensor on the actual pedal that could be going bad or it could be the throttle body itself. I worked on an 08 sierra that was having this problem and I went with changing out the pedal first considering it was the cheapest part. After changing it, there was no change, so the next step was to change out the throttle body. this part of course is more expensive but not hard to do urself. I put the new one one, the check engine light went off and the power had been restored and there has been no other power loss problems or CEL since.

I also have replaced the alternator on the same 08 sierra for the battery not holding charge. It is much cheaper to have it rebuilt than to buy a new one, just a little FYI. So if that is something that needs to be changed I would look for a rebuild shop in your area. But its not neccessarily the alternator, so if you are having no problems with the new battery then you should be fine. As for the battery coroding I cant help you with that one. Is there a way hat moisture is getting on the battery?

Chuzz

You need to just replace the cables. Once you get corrosion under the insulation, it pretty well ruins them. If they're long enough to cut off and put new connections on, then you may get away with it, but I'd just replace them. They aren't all that expensive.

07Silveradooo

The cel was on last night and then it went off this morning. The spark plugs and wires are a good place to start then if the problem continues than I'll look into the throttle body...I just don't want the problem to get worse. I believe the spark plugs haven't been changed at all..the problem is that when the cel is on I get any codes from a scanner. My dad says when the cel is off then don't worry about it. I just don't want there to be a problem later down the road

StrictlyChevy

Well I would definitely start with the plugs and wires then if they haven't been replaced. And though the light might not be coming on all the time, because it is coming on there is a problem and it does not need to go un-attended. And if it blinking like I said..that is a serious problem.

07Silveradooo

I just merged onto the highway and going from 50-70mph on the merge was such a struggle for the car....it was so sluggish it was as if I was towing something behind the car...unfortunately I won't have time to have it looked at until thursday....but I also noticed a kind of crackling sound...similar to the sound my subaru exhaust makes when I turn it off...I don't know if that's related

makaveliks

If it's making a cracking sound with the stock exhaust i'd say chances are you have a serious issue. I know I had a tahoe that did this once (loss of high rpm power, cracking sound from exhaust, and blinking cel) on the highway and I stopped had it towed the rest of the way to dallas, turned out motor spun a bearing... 6000$ for a new motor. You may not have the same issue, but uou do not want to keep driving a truck that is behaving like this.... You could have a small problem that as you keep driving just tears the motor up more and more doing more damage.

07Silveradooo

I replaced the spark plug wires and cables yesterday...the plugs weren't bad..but the cables were a bit corroded.....the problem just got worse...now the motor won't go past 4k...period. So I'm just taking it to the dealer and letting them figure out what's wrong with it. It's not exactly safe to merge on the highway or passing cars when it takes forever to get to highway speeds