Intermittant No Start????:

:banghead: <--- I love this truck this much!!! 1995 4dr 4x4 blazer obviously

A couple of weeks ago, my lovely truck decided it no longer wanted to start but only when it wanted to. I have narrowed down the issue and have been able to talk the truck into starting when I wanted it to, though I doubt my fix was good enough.

to begin with. that lovely fuel pump sound you hear immediately after you turn the ignition switch on. If i dont hear that sound, I know it's not gonna start. through arguing (and i mean litterally) with the truck one afternoon i figured out that the fuel pump relay was located in my glove compartment. and even more convenient was the horn relay located right next to it. Convienient because both were identical. Simply swapped them out, and walla. Truck worked fine without any problems. untill now (a month or so later). Now im having the same problem, but this time, if i pull the relay and put it back in, or maybe have to wiggle it a little then it will start. sometimes i may have to do this 2, 3 maybe 4 times or so before it will. Am I missing something here. When it works, it runs like a dream, no problems nothing. just as soon as you shut it off, it may not start back up without me having to mess with the relay. I would more than love to look more into my wiring, however i cant seem to fine any kind of schematic to show me what and where i need to be looking. and at this point. I'm convinced its an electrical problem.

any help or thoughts would be really nice right about now

:banghead: <--- I love this truck this much!!! 1995 4dr 4x4 blazer obviously

A couple of weeks ago, my lovely truck decided it no longer wanted to start but only when it wanted to. I have narrowed down the issue and have been able to talk the truck into starting when I wanted it to, though I doubt my fix was good enough.

to begin with. that lovely fuel pump sound you hear immediately after you turn the ignition switch on. If i dont hear that sound, I know it's not gonna start. through arguing (and i mean litterally) with the truck one afternoon i figured out that the fuel pump relay was located in my glove compartment. and even more convenient was the horn relay located right next to it. Convienient because both were identical. Simply swapped them out, and walla. Truck worked fine without any problems. untill now (a month or so later). Now im having the same problem, but this time, if i pull the relay and put it back in, or maybe have to wiggle it a little then it will start. sometimes i may have to do this 2, 3 maybe 4 times or so before it will. Am I missing something here. When it works, it runs like a dream, no problems nothing. just as soon as you shut it off, it may not start back up without me having to mess with the relay. I would more than love to look more into my wiring, however i cant seem to fine any kind of schematic to show me what and where i need to be looking. and at this point. I'm convinced its an electrical problem.

any help or thoughts would be really nice right about now


This is probably going to get me into trouble with 51% of the population, but here goes...

Your truck is exhibiting typical problems associated with a Y-chromosome deficiency. The evidence is all there:
You have to argue to get any kind of cooperation; Giving it new things provides temporary appeasement; All the logical conditions necessary for success are present, yet it refuses to accept that and function normally; The problem surfaces again in another 28 days.
Seems pretty clear to me. If you strip a cell and look at the strings of base pairs, you'll probably find that is suffers from the debilitating genetic aberration caused by the lack of a Y chromosome.

More specifically, there may be a problem with the relay socket, wiring, or it may only be coincidental that the relay "solved" the problem and the root is elsewhere. The ignition switch is not above suspicion in this case, but analysis with a meter while the problem is occurring may be the best way to determine that. Even if the vehicle has an anti-theft system, if the starter will operate (whether or not the engine starts) the security system is not likely a problem.

The fuel pump circuit should look something like this:

http://72.19.213.157/files/1991-92F-CarTBIFuelPump.jpg

Either that, or you leave it completely alone for 4-5 days while you take care of your needs on your own (walking?), wait for the episode to end, and be prepared to deal with it all over again next month.

First of all, make sure your battery is up to par. Have it tested with a load type tester. AutoZone, etc, will do it. Also make sure the battery cables and battery side posts are clean. I had the same problem on a '95 and found the battery was failing. It cranked over good, but failed to start when cold on the first 4 attempts. Once started it would do ok after driving and allowing the alternator to charge the battery. A weak battery doesn’t supply enough current for the fuel pump to reach its maximum pressure, causing a no start.

Once the battery checks out, then do other trouble shooting.

That's a Classic Sign of a Bad Ignition Wiring Harness,
QUESTION: Next time you don't hear the fuel pump whinning with the key in the on position, Look at the dash cluster, See if the "idiot lights are lit up"
Post us back with your findings.

Today if finally happend again. I checked my dash, and all lights come on normally, nothing out of the norm. As I crank it, all gauges and lights do their normal thing except it doesn't start. Like I mensioned before, all I had to do is take the relay out, and put it back in, and it starts right up.

That1guy
A Bad Ignition Wiring Harness seems to be ruled out, I'm stumped

Next time, instead of R/R the relay; try turning the key off, wait at least 10 seconds and then turn the key back on and see if the fuel pump runs. Maybe do this a couple times and then see if it will start.