Trouble Code P0300, Multiple Cylinder Misfire Detected!

[laredo1307]

Here's the new fuel injection system he's talking about. It's really not a bad deal. I've been wanting to do mine but I've spent enough money do other things so I'm holding off for a while. Plus, my current system still seems to work pretty well.

http://www.amazon.com/ACDelco-217-3...---2-145--1-0&sr=1-2&ymm=1996:chevrolet:tahoe

---------- Post added at 08:34 AM ---------- Previous post was at 08:31 AM ----------

Also, make aure you replace your cap and rotor with ACDelco parts. If you didn't do that on your spark plugs then that may be the problem as well. I tried a different brand when I first did a tune-up and learned the hard way. Once I went back with original parts everything worked out.

 

[makaveliwi]

The fuel pressure regulator may be the culprit, I would recommend replacing the entire spider though while you have the upper plenum off. While you're at it replace the lower manifold gasket too to. If you don't replace the spider at least clean out the poppits and inspect them for leaks as well. I used carb cleaner to get as much carbon off the intake and plenum as I could. Be careful of scraping, particularly around the edges. You maybe cause a vacuum leak if you leave any scrape marks. Check prices at AdvanceAutoParts.com. Use promo code TRT30 to get 30% off upto $50. Do multiple orders to Maximize your savings. Use BWD parts, they are cheaper but just rebranded Delphi parts which is an OEM for GM. Should save you a lot of money that way. Good luck.

 

[Gmc lovin75]

No white smoke out of tailpipe. Never has smoked since I have owned the truck, owner for over two years now. The SES light has not been on since yesterday. The truck finally started yesterday so I went to O'Reilly's and bought two cans of SeaFoam and filled the tank with 93+ Octane gas thinking I had possibly got bad gas. Drove around for little while, parked it and restarted it and it started immediately.

Today, after setting all night it took 8 to 10 attempts to get the truck to start. I would turn it over, let off the key and turn it over again. In between each try letting the fuel pump run until it stopped. I am beginning to think it is not bad gas. The only kicker is once it starts and runs for a few seconds it runs fine.

???????????????? I need some suggestions or advice here. Am i loosing prime over night? The fuel pump going out....? Anyone dealt with this experience?

You're losing fuel pressure somewhere as it sits all night it has time to lose pressure. I had a Bronco a few years ago and I had the exact same problem and it turned out to be a hole in the fuel line. Fixed it and it never did it again.