93 blazer wont start

Iv got a 93 4.3 vortex engine an it won't start unless I spray strating fluid in it then it will start an run till startin fluid burns out...it has good fuel pressure to where it goes into the motar I put a diff ECM in it thinking it might be that but had no luck I could use some ideas thank you

Key on, engine off, fuel pump running, fuel pressure must be 55psi to 61psi and must remain above 50psi for 3 to 5 minutes. If fuel pressure and leakdown are OK, check for battery voltage at the fuel injector connector when the ignition is in the RUN position. Post your results.

Ya I will I'm going to get a fuel presser tester this weekend and see where it goes from there thx

I got this one from Harbor Freight (http://www.harborfreight.com/fuel-injection-pump-tester-92699.html), works good.

I'm having similar fun with my 92 Blazer (http://www.automotiveforums.com/vbulletin/showthread.php?p=6830290#post6830290).

I will soon be installing my 3rd fuel pump having 159,102 miles since I bought it new in 92.

I got a fuel pressure tester yedterday but I havnt had a chance 2 use it yet I hope 2 today but I'm not sure I have 2 work on a 90 park ave it has a few bugs I need 2 work out...the blower fan for the heater isent blowing I need 2 figure out if its the fan that's not working or the relay or something else dang thing has touch pad control sys in it.. N pass front wheel breaking harder than other 3 wheels an it leaking brake fluid somewhere so all these things will delay me working on my blazzer thank u all for ur advise I will get 2 it asap thx all have a good day

I tested the fuel pressure it goes to 60 psi an hold above 50 psi for over 10 min then I checked power going to injector an it has power I guess the next step would be to take plenum off but I'm not sure what to test from there I'm hoping it is the fuel pressure regulator plz if you have any more suggestion I'd be more then glad to check it out so I don't replace parts that don't need it...thx for all your help

Your fuel delivery system is fine. The pump is building sufficient pressure and the pressure is holding, which means the pump, pressure line and regulator are all doing their job.

With the ignition ON, check both terminals of ECM/IGN 10amp fuse for battery voltage. If it's OK, pull the plenum and check for constant battery voltage on the pink with black stripe wire at the injector with the ignition ON. If that's OK, you'll need a noid light to check for pulse at the injector while cranking. DON'T use a test light, it will destroy the driver in the PCM. Most auto parts stores have the noid light. There has been an issue with the electrical connector at the injector, check it closely, make sure it's tight.

Ok thx ill get my hands on a noid light ill post back an let you no how it goes again thx alot

Advance auto parts rents these. You buy it, and return it when you're done.

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_6-Piece-Noid-Lites-Test-Kit-Performance-Tools_16990054-P_N3092_A%7CGRP2027____

Hey all I just wanted 2 let every1 no I haven't gave up or figured it out yet iv just been busy with 2 other cars I need 2 get going ill get to it soon an ill post as I go thx a lot 2 every1...I had anither question the blazer has electric 4X4 an it don't work I hit the switch an the switch lights flash but 4X4 don't engage I have a vacume pump an was wondering if I use that an turned key on if that would work so I could check that out..I thinks its prolly the electric motar on trans case or drivetrain module but there's a few test I'd like 2 do thatnk u for any an all help

There are several things that it could be. The most common problems are with the vacuum actuator under the battery tray, the Transfer Case Control Module connector, the vacuum switch on the transfer case, and the vacuum lines going to the switch.

Ya iv checked an its getting good vacum an I have changed the vacum switch on the transfercase an checked the fuse..I'm not sure how to check the drivetrain modul I have unpluged modul an plugged it in again

With the engine at idle and 4WD selected on the switch, does the vacuum actuator under the battery tray have manifold vacuum to it? And, does the cable pull in about half an inch? There is an electrical switch where the cable from the vacuum actuator connects to the right front axle tube: The switch must be activated when you select 4WD or the TCCM will command the encoder motor to shift back to 2WD.

The front axle does engage an I hear a clickin sound from 4X4 module or it did I was wondering if I used a vacuum pump an turned the key on if I could test the ele transfercase motor I have a chance to get a diff module for it but I'd like 2 find a way to test module b 4 I change it or put ECM back thx for ur help

A little bit of basics about your 4WD system... When you select 4WD hi range on the dash switch, the Transfer Case Control Module, (TCCM) "looks at" data from both ABS front wheel speed sensors and the Vehicle Speed Sensor, (VSS) in the transmission. If that data is OK, the TCCM sends a command to the encoder motor on the transfer case to shift into 4WD hi range. As the linkage in the transfer case moves during the shift, it actuates a vacuum switch on the transfer case. The vacuum switch applies manifold vacuum to the front axle actutor. The actuator cable pulls a clutch mechanism on the right front drive axle that connects the axle to the front differential. When the axle is fully engaged, it operates a switch that "tells" the TCCM that the front axle is engaged.... now you're in 4WD.

The encoder is a "stepper motor" that moves a certain distance when commanded by the TCCM and reports back to the TCCM on its position. The TCCM "knows" exactly where the transfer case shift linkage is at any given time. If the TCCM does not receive proper data at any time, from any sensor, including the encoder motor during the shift process, it will default back to 2WD hi range.

Now, to answer your question... The vacuum pump will help you determine if the front axle actuator, cable, and clutch mechanism is working and holding vacuum. It will not help with diagnosing anything else in the 4WD system. If you can hear the TCCM click, and the transfer case tries to shift, there's a good chance the axle is not engaging. Could be a lack of constant vacuum to the vacuum switch, the vacuum switch itself, the actuator under the battery tray, the cable, the clutch mechanism, or the switch on the front axle. Diagnosing the TCCM and the encoder motor will require a good shop manual, (not Haynes or Chilton).

Thx for the info I thinks its getting plenty of vacuum...the last time I tried to use the 4 wheel drive I it was like the transmission was between gears the engine would have to be at real high RPMs but the truck would barely crawl so I haven't tried engaging it since I was afraid I'd burn the transmission out an iv laid under the truck an had some1 engage the 4X4 an I could see the switch working on front axle but if it was engaging all the I dunno thx again for all your help