i posted on here a week or so again that my blazer was hard to start and now wont start. well, if it sits for a while it will start and immediately die and then no start. anyway, i replaced the ignition switch just now because from all ive read that seemed to be the consensus, but its doing to same thing. i tried to perform the passlock relearn, but the security light does not flash. could the reason its still not starting be because i havent performed the relearn? also, the fuel pump never makes a sound. thanks in advance, ian

 

BLUF- check the ground wire behind the driver wheel well on the frame for cuts and or corrosion where it contacts the frame.

You need to get a fuel pressure tester. I recently went through similar experience with a 98 ZR2. Replaced fuel pump, ignition switch and then crankshaft position sensor. Would start for 5 days or so, and then not. Drove me crazy.

Sunday night it wouldn't start. Went to Advance Auto parts and bought a fuel pressure guage. No pressure, and no noise from fuel pump. Note I installed a DELPHI fuel pump and soldered the new harness, so was confident in my install. I next swaped the fuel pump relay, still zero pressure and no fuel pump noise. Went to bed and tried to start the next morning, started right up. Fuel pump made noise.....

The problem ended up being a poor fuel pump ground. On Monday I found the fuel pump ground, which is connected to the frame behind the driver side rear wheel. The rear tail lights also share this ground. I discovered the 16 guage (black)stranded ground was crimped, and only one strand was connected. This one strand was somewhat coroded also.

I cut the strand, and trimmed back the ground wire on both ends. When I touched the wires together, the fuel pump kicked right on. When I seperated them the fuel pump made no noise. BINGO. The ground was the problem, five feet back of the fuel pump.

I pulled the ground screw out, cleaned the corrossion and dirt off the connections, soldered the spliced wire and put dielectric grease on the ground connections. Fired right up and hasbeen runing fine since.

Did I break the grounbd when i lifted the bed to instll the fuel pump.... posibbly, or the ground may have been the weak link all along. I am frustared that GM would use such a small wire and route it so far for this critical connection. This summer I will run a 12 guage wire from the fuel pump ground to the frame, a second connection.

The reason for the premature fuel pump failures is often focused on the wiring harness. After seeing this, I am not surprised.

 

i appreciate the info and ill check it out. mine is actually a blazer, but the ground should be somewhere around the same spot i would imagine. i have checked fuel pressure and its exactly 0. thanks again, ian

 

Its going to be hard to measure the fuel pump ground for continuity on the Blazer without dropping the tank.... Good luck. What state are you in(I am in northen Illinois if you need a hand).

 

thanks for the good luck wishes. im in east tennessee so come on over! lol. i have a good friend here thats from joliet. i was in chicago myself about 2 months ago.

 

replaced the fuel pump yesterday and now it runs again. still hard to start after it sits for a while and has a rough idle. im guessing the fpr is bad, but im going to look into a couple other things first. any suggestions would be appreciated. thanks

 

loaned the blazer to a buddy of mine day before yesterday and he drove it about 40-50 miles and now its doing the exact same thing it was before. i dont understand....