EDIT:
To save everyone time, the issue described below was fixed with the installation of a new ignition rotor. I first replaced the ignition switch but there was no change. I then replaced the plug wires and then the distributor cap and tried to start the blazer after each install but it didn't start until the rotor was replaced at the end.

Hey guys, I've been searching on this forum for "no start" issues due to my own problems. Seems that there are multiple threads that are started with the same issue I have and then we are left hanging with no final update/conclusion. I promise whatever happens that I will post my end results even if it is me pushing the vehicle into my pond!

I have a 2000 Blazer 4dr. 4x4 LT that when it seems to sit for more than a couple days will not start back-up. This has happened on multiple occasions when it would sit and not start. One time I was so frustrated cranking it over and over that I actually burned up the original starter! When it does start, it seems to run fine!

The engine itself cranks over just fine and after 10 or so seconds when you stop you can hear the engine sputter like it is trying to run?!?! I can sit there for 10-20 minutes doing this and it will not start. Like I said, the worst part is that when it is running there are no issues and it starts up relatively quickly (although seems to be a little longer than my other vehicles) but it doesn't take 10 seconds. Maybe 3-4. Like I said, just a little longer than usual.

I am looking to sell this truck because I just got my g/f a newer vehicle. I had the erratic gas gauge issue so I went ahead and replaced the whole fuel pump assembly while I was at it (with a geniune new AC delco unit). Erratic gas gauge solved. Also, when it was cold it would tend to "buck" a little when you first were pulling away through first and second gear. That has gone away also after the fuel pump install. While I was at it, I changed out the spark plugs and checked the rotor & cap as they are not old since my last tune-up. After the fuel pump was changed it still had a small problem starting but I was able to get it started. Ran fine for a couple hundred miles and then it sat for a few days. Go out to start it to pull it out of the garage and wash it to get ready to go up for sale...won't start. It cranks over just fine and stumbles a couple times like it wants to start but just wont "catch".

To rule out some things, the following are fairly new (within 10,000 miles) and installed by me and afterwards the truck has run w/o any problems after each install: alternator, battery, starter, fuel pump and spark plugs.

After reading some threads and some links to the fuel pressure check write-up from Swartlkk (thanks btw!), I went and bought the gauge and I am currently checking that. Here are my findings (note that I did this test a few times just in case):

When the ignition is turned on the fuel pump can be heard running and also when the ignition is turned off it runs for a short period of time also as it should.

Iginition on fuel pump running: 60 psi (should be 60-66psi)
Fuel pump shuts off after cycling the pressure drops to: 58 psi
Fuel pressure as it is cranking over: 58 psi
Pressure after sitting for 10 mins: 52-53 psi (shouldn't drop more than 5 psi)
Relieved pressure to 10 psi and after 10 mins: 10 psi (shouldn't drop more than 2 psi)

Looks to me that the fuel test data is in-line with the parameters in Swartlkk's write-up. Does this sound like the (in)famous ignition switch issues?

Thanks in advance for any responses!!

JT

 

Will it start if you use starter fluid?

Will it start if you put jumper cables to it?

I know that it is difficult to let it sit a few days to diagnose this, but either of those two things happening would give us a good direction to go in. If starter fluid allows it to start, then it is likely something fuel related. If more voltage allows it to start, then you could be looking at something with the ignition system requiring higher voltage to start..

 

Thanks for the reply Swart. Hey...I'll do whatever you guys need me to try!

Ok, I tried before I changed my fuel pump a couple weeks ago but I figured I would try again now with starter fluid...no luck. Didn't work before and doesn't work now.

The blazer has been in my garage on a battery charger to bring up the charge since I wear it down with turning it over so much and the engine not running. Anyways, the battery is fully charged and I tried to jump it...no luck. Then I tried to jump it with adding starter fluid. No luck.

Also, just to note, there is no CEL. I want to check the spark but have to wait till someone else gets home. But as I noted originally, it does run. It was running a couple days ago and it did this "no start" thing prior a couple times also.

 

If it will not start with starting fluid, then you know that fuel is not the issue. I would continue on through the ignition system looking for problems. Remove your coil and ICM (ignition control module) and take them to your nearest Autozone or Advanced Auto and have them tested. Have them tested repeatedly (>10 times) to get them good and hot to expose any heat related problems.

 

I didn't know Autozone could test the coil & ICM (I know they can check batteries, starters & altenators)? I can get them tested although I did just pull the front passenger-side spark plug wire off and there is "spark" when it is cranking.

So I have spark at the plugs, fuel up to the fuel rail and air. Could it be the injectors are not firing? What does the security system disable?...spark or fuel? I started thinking about it, the fuel pressure pretty much stayed at the same PSI while it was turning over...is that normal or should there be a drop?

 

Starting fluid should have been enough to sustain combustion. So fuel should not be the issue.

 

Just so we are on the same page, I pulled off the air intake where it dumps into the throttle body. Opened the butterfly valve and sprayed into the intake the starter fluid for about 10-15 seconds. I know back in the day of carbs, starter fluid was in every mechanic's tool chest but I've only used it to help get my snowmobiles running after fogging the engines during storage. Just want to make sure that I did it right.

I will pull off the coil and ICM and get them tested tomorrow. More to follow.

Thanks again for the help Swartlkk!! It is appreciated.

 

So long as you either disconnected the electrical connection to the MAF or reinstalled the intake duct work prior to attempting to start, yes, that should have been sufficient to fuel the engine for a bit.

 

There is a known issue with '96 to '03 Blazer-Jimmy's with the fuel delivery system. There are is a lot of information out there regarding the problem with the SCPI fuel injection module. It is an easy replacement to go to Multi-port Injection (I did it in a parking lot at a hotel I was staying at; also did the lower and upper intake gaskets while I was there...). This problem apparently only involved the S series trucks but not the fullsize pickups with the 4.3

Typical signs and symptoms of this problem are hard starting that gets progressively worse as time goes by. May run like a jalopy, etc. It may also be impossible to start if it is very wet outside. My truck had those exact symptoms and after replacing it with the updated module, my '96 ran like it was new. Please note that I also did the lower intake gaskets while I was doing this and I'm VERY glad I did. The LI gaskets were totally trashed and ready to blow out (original 12 y/o gaskets from the destructive Dex-Cool years).

http://www.gmpartsdirect.com/part_im...K125683321.JPG

I did not get the part from Gmpartsdirect.com. I bought it online from some GM dealership that I believe was in Pennsylvania for close to $200 for the actual part and the gasket kit. GMPartsDirect charges too much for shipping. Check partszoneonline.com; their prices are just a little bit higher but they don't rape you on the shipping.

Here are some better photos of the work:

http://www.s10forum.com/forum/f107/s...de-kit-324166/

Look at multiple forum threads on this issue and you won't have a problem. Gather as much info as you can get so when you go to do this you won't have any questions. We'll be here to help.

 

His symptoms and subsequent diagnosis has pretty much ruled out the fuel system. I doubt that replacing the spider at this point would do anything but lighten his wallet. I could see the spider being the issue if the truck would start on starting fluid, but it does not. This indicates an ignition problem.