hello everyone i just bought a 1994 s-10 blazer for $400 and it has the 4.3 vortec with a newly rebuilt engine with only 50,000 miles on it and it wont start cranks over dosent back fire or anything just wont start also my gauges arent working the lights for them are but there not it will start up with starting fluid but runs very rough and sounds like its gonna stall out never does though and when you press the gas it takes it a second to start getting up to speed and starts to run a little better until i stop again then runs rough all fluids look and smell fine what could be the problem?

thanks .

 

Welcome, you got a good deal on the truck. I got my 93 in not running condition for 300 bucks and with another 600 worth of parts and my own work I had a slick blazer to drive around in.

Well we know you have spark cause the ether will fire, so the next step is to see whether you have fuel delivery.

Listening, can you hear your pump buzzing when you turn your key on? The pump is in the tank, have someone turn your key while you stand by the gas filler and listen for the buzzing. If you hear the buzzing, then move on to the next paragraph.

You have a test port that you can thread a fuel guage onto on the drivers side rear engine area. It looks like a valvestem on a tire on the fuel line and has a little blue cap that threads off. You can thread a fuel pressure guage onto that if you have one, if you dont then you might want to borrow one or buy one, they are about 50 bucks or so. Your pressure should be about 58-60 psi with the key on, 50 or so when cranking and back up to 60ish when running. Then turn your key off and the pressure should not drop off any. If it drops off then we will be looking for the leak.

You may also want to take off that plastic vortec cover on top of the engine, and then take that black hockey puck looking thing off. Now grab a flashlight have have a good look in there? Is it black EVERYWHERE??? What does it look like? A leak internally is very common on these engines and most of us have had them. It will be washed a gold color if you have a leak, and should be black everywhere if all is well.

After trying to start it for a bit, pull a spark plug or six and see what condition they are in. They should not be white, they should not be black, they should not be wet. They should be dry and rust colored and have a nice big electrode and a clean gap between the bend on the end and the electrode with no crusty stuff built up on them.

Do these four checks and get back to us with what you find. We will get you running friend.

 

Well I tried the spark plugs and they actually look great haven't tried the gauge test yet will soon and for some reason my battery is being a pain if I close my door the battery stops being connected and the hockey puck looking thing is still all black what do I do now?

 

Well now you go find a fuel pressure guage or go buy one to keep for future use. If your pressure is too low the injectors wont fire at all. There really is no way to tell if you have sufficient fuel pressure without the guage.

As for the battery not working when you close your door...? I have no idea how that can happen other than a loose connection, but I would start by servicing the battery. take off the terminals, and clean all the corrosion off the terminals and the connectors. You can wash away the remaining cakey white stuff with baking soda mixed in some water. Then you put some dilectric grease or battery protector on the terminals and hook em back up again, making sure they are tight enough that you cant move them by hand.

You dont by chance have your big power wire for the stereo going through the doorjam instead of through a grommet in the firewall do you? I ask cause I have seen it happen before.

So your guages are all reading zero, but they light up??? The temperature sensor is on the passenger side of engine, just above the exhaust manifold and looks like a little gold colored spark plug top, it will have one wire hooked up to the top of it. If that wire is hooked up, then I would suspect the sensor is NFG. They are about 40 bucks, and swap it out fast cause once you undo it coolant will dump out. Oil pressure you should not have until the engine is running or has been cranking for 5 seconds or more. Your voltage comes from the alternator, there is a skinny wire hooked up to the pin on the backside of the alternator, I think it is red.

 

Does this mean you pulled the hockey puck (aka IMTV) out of the intake manifold and looked inside and it's all black, or does it mean the IMTV is still black?

If the former, ie no signs of fuel washing inside, it is more than likely your fuel pump.

If the latter, you need to pull the IMTV out of the manifold and look inside with a flashlight.

 

Hey guys yes my power cord for the stereo was going through my door jam bought it like that just ripped it out actually lol and I took it to school I go to school to be an auto mechanic and we figured out that it was the throttle positioning sensor so now it's running a little bit better no more hesitating and it goes now but it's still missing for some odd reason still have to figure that one out with the battery it's not strapped down and I think it's shaking and getting a loose connection and my gauges still don't work it also starts right up now and my timing was off we fixed that by retarding it.

 

First thing I had to replace on my 97 blazer among a long list of items was the ignition switch power distribution block.
It distributes 12v across all accessories including gauges even the delay dimmer dome lamp will stop working as this thing gets worse.
Eventually the truck will fail all together failing to supply proper voltage to the fuel pump.

I think its called ignition switch module not to be confused with the ignition module found under the hood.

I dont know if the 94's have the same setup as the 98's but im guessing they do

The culprit is in the steering column just beside the tumbler were your key goes couple torque screws if I remember right.
Large groups of wires travel down the column and plug into the main harness connector.

This is a common problem for blazers.
I e-bayed mine for under $50
You probably just need harness not the tumbler alot of parts stores only sell them as kits if i remember right. I do remember it cost twice as much when you get the tumblers.

Look around at other electrical things i thought my truck was possessed by demons until I replaced mine, then she was good as new for a min. ha-ha
good luck,
Look for it under the plastic piece that surrounds the keyhole.
Separate the two plastic half tops and bottom covering the steering column.
Its going to hang up around the keyhole but if you twist it hard enough.
The plastic will shear off from behind the keyhole and slide right off,
cosmetically you’ll never be able to notice.
Way easier than having to try and removing the key assembly.
When you get it apart you'll see two torques screws. There a little tough to get at but take your time hopefully you got the female torque tool and you should have no problem getting them out.
I think I got mine out with a 12 point tiny socket.
But I recommend using the correct female torque driver or socket one may work better than the other,
you'll see what I mean, it's a little tight to get at.

 

The power cord in the doorjam is a sign of a shoddy workmanship of the previous owners, and also a great way to start a fire. If you bought it from a friend tie a hangmans noose in that old wire you removed for him to hang himself with. The doofus that installed that obviously didnt put a fuse inline by the battery either It gets pinched when you shut the door and since there is no fuse it just dumps your battery charge into the frame of the car instead of popping the fuse that should have been inline. That should fix your voltage loss overnight. If that pinch was happening under a carpet somewhere you would have a burned out shell of a blazer in the morning. Thats why the fuse at the battery end is deadly important.

Are you getting any engine codes? You check engine light on??? Use a paperclip and jump it to get the codes and tell us what they are. You can find info on how to do the jumper method, or at your trade school just plug in an OBD1 scanner and write down your codes, then report to us. If you have a bad misfire you should be getting codes for sure.

Also, we mentioned that you should pop out that hockey puck thing (IMTV) and have a good look INSIDE that hole with a flashlight. That is your fuel injection system you see in there, and it should be black everywhere down that hole, if you have any washing in there, thats a problem. I mentoin this again cause in your reply it seems you inspected the puck itself, not inside the hole like we said.

Also want to add, have you check your fuse board out for a popped fuse for the dash, I think it will be labeled INST or GUAG... I wonder if the clown that put the power line through the doorjam also tapped into the fuse panel for power for the head unit when he hack and slashed a stereo system into your truck and caused a short that popped the dash fuse.

 

Well I can't get the hockey puck thing off I found why it's missing he changed 5 spark plugs and left one it's the one behind the steering shaft it's cracked all the way through and I got my gauges to work it was a stupid *** fuse lol she starts up everytime and I pulled all of the stereo cords it running still kinda rough because I haven't been able to get that spark plug out don't have the proper tools plan on it though glad I got my beast starting up everytime now but it's still stinking like gas bad.