I have a 1995 blazer that will not start without a small sqiurt of starting fluid into the intake once it is started and warmed up. it will start like a champ all day long. Next morning no start again. Thus far I have replaced the spider, the plugs, the cap and rotor and the wires. The pressure at the fuel rail is 60 psi with key on and motor not running and 53 psi with engine running perfect specs, per manual.When it has been running and will restart it will start with just a quick turn of key and runs like a brand new vehicle. Plenty off power, no misses no sputters no engine light no stalling. I have found MANY like problems posted all over the web and would be ever sooooooooooo grateful to antone who could solve this mystery with me.

 

It seems to me that for some reason fuel isn't getting to the injectors without the aid of starting fluid to draw fuel into the combustion chambers!! This does puzzle me since you said you replaced the spider therefore I would kinda rule that out except for the fact that it doesn't cold start unless you use starting fluid to get it going, basically priming the system is what your doing as if you had a mechanical fuel pump like on older chevy's that need a little jumpstart if sat too long!! I want to say it has something to do with the spider that you put in, so here brings a question did this happen when you put in the new spider by chance???

 

no, I put the new spider in because of this happening. I pulled the intake plenumn and discovered washing on the passenger side, and EVERYTHINGI read about this condition said to replace the spider, thuslyI did. Also prior to replaceing the spider I did have a check engine light the code to it was sporatic lean fuel,I had just assumed it would be the O2 sensor however the light went off when Ichanged the spider and the truck has never run better, once it's running of course. I am not a mechanic however I have a mechanical aptitude, I do heating and cooling repair in SEMichigan.

 

For some reason I am thinking the injectors are plugging and not allowing fuel to flow into the combustion chambers till primed and warmed up!! This is driving me nuts a little bit trying to figure this one out and help you out, I know someone will say something to aid in troubleshooting this one with me and turn the light bulb on in my head. [:@] For some reason I am thinking somewhere there is something in the system that is preventing fuel flow!! I am wondering if it could be a faulty fpr!!

 

ok,I agree that this would make sense except the fuel pressure regulator comes with the new spider and I would expect to have a miss or power loss or something else going on if that were the case, also the fuel filter has been replaced within the last year just as a regular maintenence issue. The only thing I can think of is either there is some kind of a sensor that is related to cod start or maybe whileI have proper fuel pressure erhaps I dont have proper fuel Volume? could I have pressue but not volume if the fuel line were restricted the sending unit and pump screen were replaced about 12 to 18 months ago due to leaky line on the sending unit I was areful but maybe debris in tank clogged the screen? but again I would expect some other problem like loss of power or bogging down on acceleration. I dont know I'm very frustrated at this point. I know its a 95' but it only has 77,000 miles and otherwise is a great vehicle.

 

I agree with you on that and from the fuel pressure test point back through the filter and pump is not the issue its whats forward to the motor through the spider!! When you go to start the truck when its cold do you let the pump fully kick on for a minute then go to start it?? One other question for you what is the temp overnight and in the a.m. when you go to start it?? Is it cold enough to turn water into ice by chance?? Just trying to get all possible equations out there to rule things down you know??

 

Yes, I let the pump fully cycle which is completed within 3 seconds. However sometines if I turn key on let pump cycle turn key back off wait 5 secs turn back on and repeat several times sometimes it will start or if I just "bump" key let pump cycle bump key repeatetly a few times it will start just on a bump. As to the overnight temp yes it is below freezing here and that is when the problem first started (during a cold snap of single digit overnight temps). However I have filled the tank several times since and use lucas gas treatment, also even if am temp is above freezing 45 degrees or so still same problem. It has not yet warmed here to above freezing temps durng night maybe in next week or so, so I cant yet determine if in fact it is a cold weather issue or just a coincidence. I apprciate your time and effort thank you.

 

This is a sign of still further fuel leaks internal to the plenum. If repeated priming of the fuel system works, then you have a pressure leak somewhere in the system. If the pressure completely bleeds down, the typical 'prime' run-time of the fuel pump is not long enough to fully pressurize the system to the required pressure for starting.

What happens to the pressure if you observe it over time? If it bleeds down, you have a leak somewhere in the system.

When you replaced your CPI spider, did you also replace the internal fuel lines (commonly referred to as the 'nut kit')? These lines do not like to be moved once they have been installed and heat cycled in a motor.

 

I saw that you tested the fuel pressure, but what was not addressed was the bleed down test. Hook your gauage up again to the schraeder valve , turn the key to 'on' and see if the pressure is ~55-62psi. THEN turn the key to 'off' and see if the pressure holds. It should not drop more than ~2-3psi. If it does, you possibly have a bad FPR. You may have to open the intake up again and see if there is still fuel pooling inside. I've got a sneaking suspicion it may be.

Ah, Kyle, you typed faster than I did.

 

I agree however while having vehicle in garage not a drop of fuel is on the floor which would suggest no leaks and the pressure stays at 60 if I turn key on then off after pump stops for at least ten minutes.