Im new to this, but I really dont know what else to do. I just got a 93 s10 blazer 4x4 4.3 cpi. I replaced the fuel pump, fuel filter, cpi unit ($250), icm, and pick up coil. After a good $500 in new parts, I found out that I threw it off timming. So i towed it to a shop and payed $547 (parts and labor) to reset the timing, and replace the fuel pump. I had bought a TBI pump on accident. Now it starts when it feels like it. fuel pressure sits at 10 when i first crank it, then shoots to 60 after a couple of cranks. after start up, stays at 90. i gotta pump the pedal to get her going.engine smells like fuel. i also gotta misfire so i gotta check my plugs. but the fuel pressure,or lack of, keeps her from not starting. electrical problem?

at a lost and out of cash......

 

90?? That is way too high. I'm surprised that kind of pressure hasn't blown things apart inside the plenum...

And it should hit 60psi on the initial priming of the pump... It needs to be over 55psi for the injection system to work properly.

 

you said you bought a TBI pump by mistake, did you take it back and get the correct pump for your engine? If not your always going to have starting issues. The TBI pump only gets it up to 11psi, as stated above you need at Least 55 psi to get it started and running.

 

Thanks for the help. I had to park her. The mechanic I took her to replaced the TBI pump with a CPI pump. I decided to put her away and pull the engine apart. I really got too much going on in there. I think I got ripped off when I got her. Guy sold me a piece of work. She'll be up and growling in no time.

 

whats wrong with the truck now that your ripping the engine apart?

 

okay, sorry i havent been in a while. ive been on the bus looking for work.

My blazer starts up when shes cold, and puffs like a train. WAY TOO MUCH SMOKE. my fuel pressure that was at 90 psi probly blew the head gasket. i got a lot of carbon dripping out the pipe and a code 45 from the dash. the coolant level drops, but not at an extreme amount. she burns gas, unbeliveably. I pulled the fuel pump relay off and turned the key to relieve the fuel pressure like the book said, but the blazer turned over. i thought it may had been the wrong relay so i pulled both of them and my engine still fired up. maybe there is a fuse somewhere else? to try and make this simplier here is a list of problems from start to finish:
1. no start.
guy i bought it from said i needed a new wire harness. for some reason i changed fuel pump, filter, and spyder but never got a new harness.

2. fuel pressure too high.
took her to a shop and got her going. but the pressure is at 90 psi. autozone said thats how she is supposed to be. sometimes she doesnt start at all. too much pressure or no pressure at all.

3. Smoking like a train.
probly blew a head gasket. havent touched her yet.

i love blazers and this is my first one. im 21 years old and the only man in the house so im kinda alone on this project. any help from any experianced mechanic will help.
P.S. my #3 spark plug is blocked by my stering rod. i cant get the spark plug socket on. any special tool or do i unbolt the rod? universol joint wont fit between the rod and the plug.

 

You might as well ask the cashier at walmart what the fuel pressure should be, because thats all an autozone employee is "a cashier" They're not mechanics. just fyi

 

Have you found the fuel leak yet? You can buy yourself a fuel injection pressure gauge for 40 bucks max that will aid you tremendously in fixing your problem. Dont give up on it after your spent that money. You cant blow the head gasket from high fuel pressure, the injectors spray into the intake runners. If you have a leaking head gasket, there is tests and check for that. You will have chocolate milk for oil, and the oil will be too high all the time. You may have floaties in the coolant? You can get a compression tester for about 40 bucks and check the cylinder compression. These are all things that your 575 dollars should have covered checking out when it was at the mechanics.

Heck, look around your neighborhood for a guy like me who always has the garage door open and car parts on the driveway... Hes the kind of guy you can borrow these testers from and not have to buy anything. Ive had neighbors come borrow tools because "my garage door is always open and Im working on things"

Keep posting in here, and reading threads. We'll get your truck going with ya. I hate reading that someones taking the bus when they have a blazer in the yard...

Oh yeah, and try putting another 20 inches of extention on the spark plug socket and go in above your drivers side tirein the wheelwell. Lift up that little rubber flap and what do you see? A steering rod wth a spark plug underneath staring at you.

Heres your task list:
-Find a shade tree mechanic and borrow, or maybe he will come test for you with his gauges.
-Check fuel pressure and write down for us, 90psi is not possible, I think your mechanic was reading it upside down. We need to know what it is when you turn the key on... What it is when you are cranking... And what it is when you turn the key off (it may bleed off fast)
-Check your compression on all cylinders, this is where the head gasket leak will show up. Unhook the harness to your coil so the engine cant start and remove all 6 plugs. Crack the engine for at least 5 rotations and let us know the pressures on each cylider, write them down. They should all be between 100-130psi.
-After its been sitting a while, take your oil drainplug almost out... If any green stuff comes out thats bad, if its oil, then no problem.
-Have a good look with a little mirror and light down behind the intake, where the intake meets the heads for a coolant leak, at the sides of the base of the distributor. These engines have no crossover for coolant on the back of the intake, only the front, so junk builds up here and rots away the gaskets. Small leaks here dont typically leave spots on the ground because the coolant runs down the bellhousing and drips onto the exhaust pipe. You might smell a sweet smell if you could get it running and hot.

 

I was able to get a spark plug socket on the number 3 plug then I used a crescent wrench to turn the plug worked real good actually