Morland1

My 99 ½ ton Chevy 4X4 2 door Tahoe would not start yesterday morning. I drove it the night before to pick up dinner and it ran okay. It was not my daily driver until about 6 months ago when a 16 year old ran into my pickup at an intersection, which of course the insurance company totaled out the 90 pickup with 280,000 miles on it. I need to get busy and get it going again because I hate being without a pickup. Will enough about that. I am currently down to one vehicle and need to get my 99 Tahoe running this weekend, so any help would be appreciated. I am a Do It yourselfer, but I will admit sometimes I probably shouldn’t have.
Info on the 99 ½ ton 4X4 with a Vortec 5.7:<O</O
It only has around 63,000 miles on it, and I have been only owner. It was just used as the third vehicle until about 6 months ago, now it is a daily driver. I changed the distributor cap and rotor about 4 years and about 12,000 miles ago. It has not been abused at all, besides not being used as it was meant to be. I have noticed that the last month or so it sometimes took a little longer to start than normal. It has had a lower Intake Manifold antifreeze leak for quite a few years, not a big leak but enough to leave a little wet spot on the ground after it sets a day. It does set outside now and it did rain about 2 inches here in Texas the day before it would not start. And when driving it to work 2 days ago in the rain I did notice that when I got up to about 50 miles per hour or so, it felt like it cut out or miss fired once or twice. It did this 2 or 3 times, after that I stomped on the gas and it seemed to run okay after that. I went out yesterday morning to start it, I just reached inside to start it without pushing gas pedal at all. When I stopped cranking it sputtered like some cars do when you shut them off and they try to keep running. I have not been able to get it running since. I filled up with gas 3 days before this and it has about a half of a tank of gas now. The fuel pump is really loud and I can hear it running when I turn the key on and stops after a bit like it has built up pressure, (the way it has always worked) . <O</O
Last night I checked a few things: I pulled the number 1 plug and connected it to the plug wire, and had my son crank Tahoe over. It seemed to have a great spark, and seemed to fire quite a bit when cranking, so I believe it is firing good, but maybe not when it should be (or maybe not in time). The plug did look wet like it might be flooded. I pulled the distributor cap and it looked ok, maybe a little corroded not bad. After I thought it might be flooded I pulled the fuel pump relay fuse, and cranked it over for a while, did not seem to help any, even after replacing relay fuse. I also tried pouring some gas in throttle body, which did not help.<O</O
I know it sound like a fuel issue, but I don’t believe it is the fuel pump. I am going to pick up a pressure tester tonight and check the fuel pressure. I have had to replace the fuel pumps in my 90 Chevy pickup and also on a 2000 Tahoe, both of these had high 100,000 miles on them when replaced. I am going to check the fuel pressure but I just don’t believe it is the pump. <O</O
After reading some forums yesterday I was ready to change out the Intake manifold gasket, thinking after the rain we had maybe moisture was causing a problem, but after it still would not start last night after siting all day, I am not sure this is causing the starting issue, but does need fixed, and may replace it also this weekend, but would like to get it started again first. <O</O
After changing oil last weekend I did put synthetic oil in it for the first time ever, I never put synthetic oil in any of my other high mileage vehicles, but thought it wouldn’t hurt. I know this is not the issue, but it was something I did in the last week. <O</O
Okay, I know this is probably a long one but I wanted to make sure I stated everything I have noticed recently about the way it has run. Is it possible it could be the crank sensor? Any help would be greatly appreciated as what to check, before I really tear into it. <O</O
Thanks for your help,<O</O
Calvin<O</O

go-part

If you can eliminate fuel as being the problem then i would look at the crank sensor.

Have you checked the fuel filter?
It could possibly be the camshaft position sensor..

Morland1

Thanks for the reply Go-Part. I got it started tonight.
When I posted my problem this morning, the Crank Sensor was going to be my first part to replace. But after I posted I read some more forums, and I read a lot of problems with non GM distributor caps and rotors. So when I got home tonight I found my original cap and rotor in the garage, for some reason I never throw old parts away. Tried starting the Tahoe before I did anything, no go. Replaced the cap and rotor and it started right up. With it firing like it was I would not have thought it would have been either the cap or rotor. On the way home I picked up a fuel pressure tester from Auto Zone, and I went ahead and checked the fuel pressure, which was about 52 running and 58 not running with key on. The Bad cap and rotor is only about 4 years and about 12,000 miles old. They were made my Duralast Gold still had the box, and I think has a warranty from Auto Zone, will have to check but not sure I want another one, will probably go back to GM. I found the receipt in the box, I paid $55 for them, wow, would think they would last longer. Hope this helps anyone that comes across this post with a similar issue.
Now in the morning I will have to try and find the torx screwdriver I dropped down the back of the engine which did not make it to the ground.
Calvin